Category Archives: Sugar and Obesity

The Peter Attia Drive Podcast: Longevity, Lipidology, Fructose, and How To Keep Your Face And Joints Young

Lately while exercising I’ve been binge-listening to podcasts from Peter Attia, a cancer surgeon turned “longevity” doctor.

I first encountered his writing while researching ketosis, the Atkins diet and low carb diets in 2012 and found his writing to be incredibly well-researched, detailed and helpful.

I appreciate how he never opts for oversimplification of a topic as this disclaimer at the begining of his post on ketosis indicates:

If you want to actually understand this topic, you must invest the time and mental energy to do so.  You really have to get into the details.  Obviously, I love the details and probably read 5 or 6 scientific papers every week on this topic (and others).  I don’t expect the casual reader to want to do this, and I view it as my role to synthesize this information and present it to you. But this is not a bumper-sticker issue.  I know it’s trendy to make blanket statements – ketosis is “unnatural,” for example, or ketosis is “superior” – but such statements mean nothing if you don’t understand the biochemistry and evolution of our species.

When I first came across his writing he was obsessively monitoring his beta-hydroxy butyrate levels on a ketogenic diet and was partnering with Gary Taubes to launch “the Manhattan project of nutrition”, the Nutritional Science Institute. (NUSI) . Designed to help fund good nutritional research with the ultimate goal of reducing obesity and testing the hypothesis that “all calories are equal” NUSI, unfortunately has floundered (see here.)

He’s always been very rigorous in his thinking and writing in the areas of nutrition, diet and longevity and he is quite brilliant and knowledgeable down to very basic areas of biology and metabolism.

He has started  a podcast in the last year that has featured in depth conversations with some really interesting physicians and scientists. It’s described thusly : “The Peter Attia Drive is a weekly, ultra-deep-dive podcast focusing on maximizing health, longevity, critical thinking…and a few other things. Topics include fasting, ketosis, Alzheimer’s disease, cancer, mental health, and much more.”

The first one that I listened to was with Thomas Dayspring, M.D., FACP, FNLA, a world-renowned expert in lipidology and a fantastic teacher.  If you’d like to dive deeply into cholesterol metabolism, lipid biomarkers, the mechanism of atherosclerosis and cholesterol treatment options, this is a great way to start. 

It’s a five part, 7 hour series of podcasts with the first one here

Some Eye-opening Thoughts About Processed Foods, Sugar and Fructose

Most patients are not going to be up for deep dives into lipidology but I highly recommend Attia’s discussion with Robert Lustig.

I quoted Lustig in a 2015 post entitled “Fructose and the Ubiquity of Added Sugar”

Robert Lustig, a pediatric endocrinologist has talked and written extensively about fructose as a “toxin.” You can watch him here. He’s also published a lot of books on the topic including one which identifies the 56 names under which sugar masquerades.

Lustig is a passionate, articulate and compelling speaker who has contributed significant research in this area. Most recently he has retired from clinical practice and obtained a law degree with the goal of trying to change US food policy.

Attia does a great job of interviewing him as he helps clarify points and guides  Lustig into specific real world problems such as what to feed your children.

In addition, Attia’s staff do a great job of providing “show notes” which summarize the important points, adding helpful context and links and summarizing the content.

Lustig firmly believes:

‘Fructose and glucose are not the same: the food industry would have you believe a calorie is a calorie, a sugar is a sugar…and it is absolute garbage: they are quite different, and it does matter’

Fructose is a monosaccharide that combines with the monosaccharide glucose to form sucrose, which is what most people recognize as table sugar. Processed foods commonly contain a lot of added fructose-containing sugar but also, increasingly they contain high fructose corn syrup (HFCS) which contains up to 65% fructose.

High intake of fructose goes hand in hand with consumption of processed foods. Approximately 75% of all foods and beverages in the US contain added sugars. Consumption of added sugar by Americans increased from 4 lbs per person per year to 120 lbs per person per year between 1776 and 1994. Thanks to a dramatic increase in sugar-sweetened beverages, American teenagers consume about 72 grams of fructose daily.

There are a substantial amount of observational, short-term basic science, and clinical trial data suggesting that all this added sugar, especially fructose, are posing a serious public health problem and Lustig lays out a compelling narrative in this podcast.

Lustig discusses the  fundamental biochemical differences between glucose and fructose- whereas glucose is the energy of life for all animals, fructose is “vesitigial to all animal life” and is basically a storage form of energy for plants.

Your gut bacteria are more adept at metabolizing fructose than you are

Ludwig points out that fructose accelerates the Amadori rearrangement: the browning of your body tissues and potentially contributing to aging. Fructose does not suppress the hunger hormone ghrelin as glucose dose thus “When you consume a lot of fructose your brain doesn’t know you’ve eaten and so you end up consuming more”.

Finally, Ludwig notes, fructose in contrast to glucose behaves like cocaine on the brain. Fructose specifically lights up the reward center ‘and now has been shown to induce the same physiology in the brain that cocaine, heroin, nicotine, alcohol, or any hedonic substance also generates’

There is not a clear scientific consensus on many of Lustig’s points to be honest but he is a very convincing advocate of avoiding sugar in general and fructose in particular from non-real food sources.

There’s a whole lot more in this discussion that is important to at least think about:

-A detailed discussion of NASH and NAFLD (fatty liver disease that is becoming common in obese Americans.)

-Why you need both soluble and insoluble fiber together as opposed to added soluble fiber in a supplement or processed food adition.

-How to change the food system in which 10 companies control almost 90% of the calories consumed in the US

-the importance of eliminating government food subsidies which make junk food cheap. 

-How eliminating food subsidies wouldn’t change the price of wheat or soy, only corn and sugar which where most of our dietary sugar comes from.

Maintaining Youthful Appearance And Function-The Face and The Joints

Attia’s other podcasts touch on many other issues related to longevity. I found his interview with Brett Kotlus, a New York City oculofacial plastic surgeon who specializes in both non-surgical and surgical cosmetic and reconstructive procedures of the eyes and face (How to look younger while we live longer) to be surprisingly enlightening and engrossing.

Attia’s website and podcasts are refreshingly free of advertising and any annoying teasers. This description of the Kotlus podcast is about as close to a mass-market teaser as you will see:

“Using these powerful basics, I’ve seen amazing changes.” —Brett Kotlus, referring to the 3 simple tools people can utilize to protect and rejuvenate their skin

I will not reveal the “3 simple tools” here but the show notes indicate you can skip to the 46 minute mark to hear about them.

Most recently I’ve been listening to his podcast with Dr. Eric Chehab, orthopedic surgeon and sports medicine specialist (Eric Chehab, M.D.: Extending healthspan and preserving quality of life (EP.36).)  As Attia points out, longevity is related to both healthspan and lifespan and our joint health is a major contributor to healthspan.

In this episode, Chebab “explains the measures we can take to live better and maintain our physical health through exercise and the avoidance of common injuries that prove to be the downfall for many. He also provides valuable insight for those weighing their treatment options from physical therapy to surgery to stem cells.”

Because the show notes are so detailed you can read exactly what is discussed in these podcasts and when. For example, if you wanted to skip the early discussion on Eric’s training, fellowship with the New York Giants, and the risk vs. reward of playing football (39:15) and listen to the discssion on The knee joint: common injuries, knee replacements, and proper exercise ” you know to skip to [1:00:00].

Personally, I found all of the preliminary discussion on Springsteen, Pearl Jam  and Chebab’s pre-medical school adventures fascinating.

I highly recommend recommend Attia’s podcasts: they are always enlightening, unbiased, objective and mentally stimulating.

In the world of longevity doctors he is unique in offering solid science-based recommendations and information free of hype,  bias and woo.

Skeptically Yours,

-ACP

The Pearson Potato Theory of Obesity

The skeptical cardiologist developed “Pearson’s Potato Hypothesis” aka the potato theory of obesity a few years ago but became bogged down in frying oil and never published it.

Now I’m really glad I never got around to finishing my post on the theory-it appears that defenders of the potato are legion and vocal. ConscienHealth points out that a NY Times piece on the dangers of french fries quoted a Harvard epidemiologist  (Eric Rimm) as calling potatoes “starch bombs” and weapons of “dietary destruction.”

Potatoes rank near the bottom of healthful vegetables and lack the compounds and nutrients found in green leafy vegetables, he said. If you take a potato, remove its skin (where at least some nutrients are found), cut it, deep fry the pieces in oil and top it all off with salt, cheese, chili or gravy, that starch bomb can be turned into a weapon of dietary destruction.

The article goes on to recommend portion size control when dealing with French fries and further quoted Rimm:

“There aren’t a lot of people who are sending back three-quarters of an order of French fries. I think it would be nice if your meal came with a side salad and six French fries.”

Apparently the notion of limiting one’s French fries is abhorrent to many and Rimm has been attacked by thousands in the twitter-sphere.

I happen to think he’s right so I’ll go out on a limb here and post the essence of my theory without all the backing references and statistics with which I had hoped to buttress it.


Pearson Potato Theory of Obesity:

Because potatoes are cheap,  restaurants add lots of them to dishes to make the dishes seem larger and (to some) better and more satiating. Because the potatoes are so gosh darn tasty when sliced up thinly and fried and salted patrons can’t resist eating them even when they are not hungry. Eating any food when you are full is a recipe for….obesity.


To illustrate this issue I’ve started noting what restaurants serve along with the main dish that I’m interested in.

The vast majority of time breakfast orders come with fried potatoes like those below that came with the egg dish that I ordered.potato egg

I was sorely tempted to eat all these fried potatoes although full from my egg dish because when cooked properly the combination of the crispy fat, salt and warm fluffy potato interior is irresistible. Instead I ate just a few and put the rest in a to-go box, took them home, weighed them on a scale and took this picture.

IMG_8758

Interestingly, the weight of the potatoes that I had not consumed was 150 grams which is roughly equivalent to a large order of fries at McDonald’s. A large order of McDonald’s fries gives you 500 calories with 66 grams of carbohydrates,.

Thus, if I had not been disciplined that morning I likely would have ended up consuming more calories in fried potatoes than the main dish and over half of the calories I consume in a typical full day.

French fries (and their (equally addictive to me) cousin the potato chip) are the side for almost all hamburgers and sandwiches served in the US thus the possibility of unintended excess starch bomb consumption extends from breakfast to lunch to dinner in meals consumed outside the home.

Sweet Potatoes Versus Potatoes

In 2015 I pointed out that sweet potatoes which are embraced by nutrition experts are very similar nutritionally to potatoes.

A serving of either one provides 37 grams of carbohydrates and 4 grams of protein. Sweet potatoes have more fiber ( 6 grams vxs 4 grams) but more sugars (12 grams vs 2 grams.)

The Harvard School of Public health has decided potatoes are not a vegetable:

“However, potatoes don’t count as a vegetable on Harvard’s Healthy Eating Plate because they are high in carbohydrate – and in particular, the kind of carbohydrate that the body digests rapidly, causing blood sugar and insulin to surge and then dip (in scientific terms, they have a high glycemic load).”

but gives sweet potatoes a pass.

If sweet potatoes were as ubiquitous as potatoes and became a staple of fast food restaurants and a side for any and all dishes (and if they were separated out from the rest of the vegetable world), I suspect they would also be associated with weight gain.

If, on the other hand, potatoes were not markers of fast, tasty, and easily prepared and consumed food and were only eaten at trendy locavore restaurants or prepared at home, I think they would no longer be associated with obesity.

So, yes it does make sense to ask for a side salad and limit your fries to six (or perhaps seven on days of debauchery) in place of the typical mountain of potato if you are seeking weight loss.

Spudlimitingly Yours,

-ACP

Heart Healthy Breakfast Choices?: Cheerios, Honey-Nut Cheerios and Soluble Fiber Revisited

A reader commenting on my Plant Paradox post questioned nutritional  recommendations to consume fiber. This has prompted me to revisit a post I wrote in 2014 on Cheerios and Soluble Fiber.

I mentioned at that time that Honey-Nut Cheerios was the #1 selling ready-to-eat breakfast cereal and Cheerios #4. This update Screen Shot 2018-07-15 at 7.22.55 AMindicates little has changed in the rankings or consumption of breakfast cereal since then despite a more widespread recognition that added sugar is the major toxin in our diet and that these food items are basically a vehicle for sugar.

Apparently, Americans believe honey is not sugar. But Honey Nut Cheerios contain 9 times as much sugar as cheerios. Here are the top ingredients:

Whole Grain Oats, Sugar, Oat Bran, Corn Starch, Honey, Brown Sugar Syrup, Salt, Tripotassium Phosphate, Rice Bran Oil and/or Canola Oil,

General Mills tries to emphasize the healthiness of Honey Nut Cheerios, focusing on their close relationship with bees and the natural goodness of honey in its advertising along with other factors that we now know are not important (low fat, 12 vitamins and minerals, source of iron).Screen Shot 2018-07-15 at 7.56.32 AM

Little has changed with respect to the science supporting fiber consumption to reduce cardiovascular disease since 2014.  It is still weak and based on observational studies and surrogate biomarkers.

Between the lines below is my original post with current annotations in red.


The skeptical cardiologist usually eschews the breakfast offerings in the Doctor’s lounge. I’m not really interested in consuming donuts, muffins, or bagels with their high carbohydrate load. As I’ve ranted out about previously, the only yogurt available is Yoplait low fat , highly sugared-up yogurt which is arguably worse than starting the day with a candy bar.

A selection of breakfast cereals is available including Cheerios, Raisin Bran, and Frosted Flakes. Occasionally, when I have neglected to bring in my own full-faty yogurt, granola and/or fruit I will open up one of the Cheerios containers and consume a bowl mixed with 2% milk (full-fat, organic milk which I passionately advocate here and here is not available) (2018 update, I have said “cheerio” to all breakfast cereals and no longer eat Cheerios in the doctor’s lounge). 

Pondering the Cheerios packaging and the cute little O’s made me wonder whether this highly processed and packaged food with a seemingly endless shelf life was truly a healthy choice.

The “Ready-To-Eat”  And Allegedly Heart-Healthy Cereal

Cheerios and Honey-nut cheerios were  the #4 and #1 breakfast cereals in the US in 2013, generating almost a billion dollars in sales. Both of these General Mills blockbusters undoubtedly have reached their popularity by heavily promoting the concept that they are heart healthy.

The Cheerios label is all about the heart. The little O’s sit in a heart-shaped bowl. A prominent red heart with a check inside it attests to the AHA having certified Cheerios as part of its checkmark.heart.org program. Additional text states “low  in Saturated fat and cholesterol” and “diets low in saturated fat and cholesterol may reduce the risk of heart disease.”

Is The Fiber In Cheerios “Heart-Healthy” ?

Beta-glucan is a soluble fiber primarily located in the endosperm cell wall of oats. Early studies showed that oats and beta-glucan soluble fiber could reduce total and LDL (bad cholesterol) levels. The mechanism isn’t really known. (see the end of post for possible mechanisms). The Quaker oats web site oversimplifies the mechanism thusly :

“In your digestive tract, it acts as a sponge, soaking up cholesterol and carrying it out of the body”

This narrative fits with the oversimplified and now discredited descriptions of atherosclerosis which attribute it directly to consumption of cholesterol and fatty acids. See here if you’d like to appreciate how complex the process truly is.

The FDA Sanctions Oats As Heart Healthy

In 1997, the FDA reviewed 33 studies (21 showing benefit and 12 not) and decided to allow a health claim for foods that contain oats and soluble fiber. A minimum dose of 3 grams/day of oat beta-glucan was suggested for a beneficial reduction in blood cholesterol and (presumably, although never documented) a subsequent decline in coronary heart disease.

In 1998 Johnson, et al, published the results of a study funded by a grant from General Mills that showed that  inclusion of whole grain oat ready to eat cereal providing 3 grams of beta-glucan as part of a low fat diet reduced  LDL cholesterol by 4% after 6 weeks. HDL was unchanged. Patients in this study consumed 45 grams (1.5 oz) of cheerios at breakfast and then again in the evening. There was a total of 3 grams of soluble fibre in this amount of Cheerios. A control group consumed corn flakes in a similar fashion without change in LDL.

General Mills took this weak data and ran with it and began posting on Cheerios the following statements

 “Did you know that in just 6 weeks Cheerios can reduce bad cholesterol by an average of 4 percent? Cheerios is … clinically proven to lower cholesterol. A clinical study showed that eating two 1 1/2 cup servings daily of Cheerios cereal reduced bad cholesterol when eaten as part of a diet low in saturated fat and cholesterol.”

Although the FDA had approved verbiage indicating oats may reduce heart disease “when eaten as part of a diet low in saturated fat and cholesterol” the agency objected to General Mills claiming that Cheerios lowers cholesterol “when eaten as part of a diet low in saturated fat and cholesterol”.

The FDA  issued a warning letter to General Mills in 2009 in which the agency alleged “serious violations” of the FDC Act in the label and labeling of Cheerios cereal.

Based on claims made on your product’s label, we have determined that your Cheerios® Toasted Whole Grain Oat Cereal is promoted for conditions that cause it to be a drug because the product is intended for use in the prevention, mitigation, and treatment of disease.

Lowering Cholesterol Is Not The Same As Preventing Heart Disease

The FDA was telling General Mills that it was OK to say that Cheerios may reduce heart disease but not that it can reduce cholesterol because that made it a drug. It makes no sense.

The only thing that had been demonstrated for oat soluble fiber and Cheerios in particular was a reduction in cholesterol. There has never been a study with oats showing a reduction in heart disease..

It’s the heart disease, the atherosclerosis clogging our arteries and causing heart attacks and strokes that we want to prevent. We could care less about lowering cholesterol if it doesn’t prevent atherosclerosis.

A recent review of studies since the FDA ruling shows that 70% of studies show some reduction in LDL with beta-glucan. Interstingly, the studies which added beta-glucan to liquids were generally positive whereas addition to solids such as muffins usually did not show benefit.

I’m going to accept as evidence-based the claim that whole oats can lower your LDL about 7% if you consume a very large amount of them on a daily basis.

However, the critical question for any drug or dietary intervention is does it prevent atherosclerosis, the root cause of heart attacks and strokes. There has been in the past an assumption that lowering cholesterol by any means would result in lowering of atherosclerosis.

This theory has been disproven by recent studies showing that ezetimibe and niacin which significantly lower LDL do not reduce surrogate markers of atherosclerosis or cardiovascular events any more than placebo when added on to statin drugs. (There is now weak evidence that ezetimibe does lower cardiovascular events ). The recently revised cholesterol guidelines endorse the concept of treating risk of atherosclerosis rather than cholesterol levels.


 

I do like the food writer Michael Pollan’s simple rules to “Eat Food. Mostly Plants. Not Too Much.” and this NY Times piece summarizes much of what is in his short, funny and helpful Food Rules book:

you’re much better off eating whole fresh foods than processed food products. That’s what I mean by the recommendation to eat “food.” Once, food was all you could eat, but today there are lots of other edible foodlike substances in the supermarket. These novel products of food science often come in packages festooned with health claims, which brings me to a related rule of thumb: if you’re concerned about your health, you should probably avoid food products that make health claims. Why? Because a health claim on a food product is a good indication that it’s not really food, and food is what you want to eat.

If you follow Pollan’s dictum you will get plenty of fiber, soluble or otherwise and you will avoid the necessity to obsess over the macronutrients in your diet, fiber or otherwise. Throw in some Cheerios and oatmeal every once in a while if you like them;  in their unadulterated state they are a heart-healthy food choice.

Cheerio,

-ACP

The Skeptical Cardiologist Answers Good Questions: Retesting For Symptomatic Benign PVCs?

One of the many things I enjoy about writing this blog is the interesting comments and questions that readers post. Many of them stimulate me to better answer and inform my patients.

Here’s one such question (about premature ventricular contractions):

Wondering your opinion on retesting. I’ve had PVCs since I was 15 (63 now) and they have come and gone over the years, attributed to hormones, low potassium, stress, and dehydration/bad diet. Recently they started again and are driving me insane and none of the usual fixes are working. Two ER visits with normal EKGs and my cardiologist all say no worries. I’m thinking maybe I should have another ultrasound, buy MD doesn’t think it’s necessary. I had a perfectly normal cath in 2015 but no tests since. Your thoughts? Thank you.

This was the response I typed off the top of my head:

Good question. I consider retesting for patients who have not had documentation of “structurally normal heart” for some time and who have a significant change in their symptoms. You would qualify since no testing in 3 years and worsened symptoms.
Typically I would order a stress echocardiogram which allows a reassessment of both LV structure and function and for any blockage in the coronary arteries and I would consider some kind of monitor-a 24 hour Holter would be fine if you are having daily symptoms.
You might also consider acquiring an AliveCor device to monitor your rhythm with symptoms. I’ve written a lot about this elsewhere on this site. Unfortunately AliveCor does not identify PVCs but if you connect via KardiaPro with your physician your recordings can be viewed and interpreted by him/her.

The answer reflects my clinical practice, which is based on 30 years of experience taking care of patients with PVCs, in conjunction with regularly reading papers, reviews and guidelines in this area.

Periodically, both for specific patient problems and for blog questions, I will search the medical/scientific literature and review guideline publications to see if there is any new information that I am unaware of to ensure that my recommendations are scientifically grounded.

In this case, a more prolonged search of the literature did not yield precise guidance on the frequency of retesting of patients with benign PVCs.

This 2014 guideline comments briefly on the evaluation and treatment of PVCs without structural heart disease (SHD):

In the absence of SHD, the most common indication for treating PVCs remains the presence of symptoms that are not improved by explanation of their benign nature and reassurance from the physician.

In addition, some patients may require treatment for frequent asymptomatic PVCs if longitudinal imaging surveillance reveals an interval decline in LV systolic function or an increase in chamber volume.

For patients with  >10,000 PVCs/24 h, follow-up with repeat echocardiography and Holter monitoring should be considered.

In patients with fewer PVCs, further investigation is only necessary should symptoms increase.

It should also be recognized that PVC burden often fluctuates over time.

This initial testing approach corresponds closely to what I wrote in my post on benign PVCs here.

Retesting with echocardiography and Holter monitoring is advised for those few patients who have lots of PVCs, but the frequency of this retesting is not specified and cardiologists have to use their best judgement, balancing the cost (to patient and to society) and patient safety.  Most cardiologists will err on the side of more frequent repeat testing for a variety of reasons.

Personally, I will advise an annual echocardiogram to such patients since they are at a higher risk of developing a cardiomyopathy.

In the absence of really frequent PVCs (>10,000 per 24 hours is a nice round number, but the precise cut-off is debatable), we should probably only repeat testing if the patient recognizes a significant change in their symptoms.

The reader clearly fits into that category, and retesting in her will provide reassurance that all is still good with her heart. This, in turn, should help with managing symptoms and preventing recurrent ER visits.

The final question (and the toughest) that we could pose related to retesting is “What is the time interval that one should wait before retesting in a patient with worsened symptoms?”

For example, if the reader had a normal echocardiogram 6 months ago should we repeat it when symptoms worsen? My reflex answer would be no, but at some time interval depending on the individual characteristics of the case-patient risks for heart disease, patient anxiety levels, patient symptom severity and frequency, the answer would become yes.

Cardiologists have to answer dozens of questions like this daily.  There is no science to inform a precise answer, consequently the answers will vary wildly from one cardiologist to another depending on a variety of factors specific to the cardiologist.

Those cardiologist-specific factors are complex and sometimes controversial. Part of this makes up the art of medicine and part reflects the business of medicine. They are definitely worthy of another post when time permits.

Questioningly Yours,

-ACP

N.B. The Eternal Fiancee’ (my layperson surrogate) expressed surprise that one could have 10 000 PVCs per day. I told her that if your heart beats roughly once per second (6o beats per minute) since there are  60 x 60 x 24 = 86400 seconds in a day, your heart beats almost 90 000 times in 24 hours.

Thus, roughly  1 in 9 beats is a PVC.

Low-Fat Versus Low-Carb Diet: DIETFITS Show Both Can Work If They Are “Healthy”

In the ongoing nutritional war between adherents of low-fat and low-carb diets, the skeptical cardiologist has generally weighed in on the side of lower carbs for weight loss and cardiovascular health.

I’ve questioned the vilification of saturated fat and emphasized the dangers of added sugar. I’ve even dabbled in nutritional ketosis.

The science in  nutrition is gradually advancing and the DIETFITS study recently published in JAMA is a welcome addition.

DIETFITS is a  really well done study which provides important insights into three huge questions about optimal diet:

  1. Should we choose a low-fat or a  low-carb diet for  weight loss and cardiovascular health?
  2. Do baseline insulin dynamics predict who will respond to low-fat versus low-carb diet?
  3. Can we predict who will respond to low-fat versus low-carb by genetic testing?

The Details Of DIETFITS

Stanford investigators recruited 609 San Francisco area individuals between the ages of 18 to 50 years with BMI of 28 to 40  and randomized them to a “healthy” low-fat diet or a “healthy” low-carb diet.

During the first 8 weeks of the study, low-fat participants were instructed to reduce fat consumption to <20 gm/ day while the low carb participants were instructed to reduce digestible carbohydrate to <20 gms/day.

Then individuals were allowed to add back fats or carbs back to their diets in increments of 5 to 15 g/d per week until “they reached the lowest level of intake they believed could be maintained indefinitely.”  Importantly no explicit instructions for energy restriction were given.

The “healthy” instructions for both groups were as follows

  1. maximize vegetable intake
  2. minimize intake of added sugar, refined flours and trans-fats
  3. focus on whole foods that are minimally processed, nutrient dense and prepared at home whenever possible

Dietfits Outcomes-Diet And Weight

Major findings

  1. Total energy intake was reduced by 500-600 kcal/d for both groups
  2. The low-fat vs the low-carb intake at 12 months was 48% versus 30% for carbs, 29 vs 43% for fat and 21 vs 23% for protein.
  3. Mean 12 months weight change was -5.3 kg for low-fat vs 6-6.0 kg for low-carb which was not significantly different
  4. There was no difference between groups in body fat percentage or waist circumference
  5. Both diets improved lipid profiles and lowered blood pressure, insulin and glucose levels
  6. LDL (bad cholesterol) declined more in the low-fat group whereas HDL (good cholesterol) increased more and triglycerides declined more in the low-carb group.

Thus both diets were successful for weight loss and both improved risk markers for cardiovascular disease after a year.

DIETFITS- Can Genes and Insulin resistance Predict Best Diet?

Surprisingly, the study found no significant diet-genotype interaction and no diet-insulin secretion interaction with weight loss.

This means that they could not predict (as many believed based on earlier studies) who will benefit from a low carb diet based on either currently available genetic testing or a generally accepted measure of insulin resistance.

As the authors point out, these findings “highlight the importance of conducting large, appropriately powered trials such as DIETFITS for validating early exploratory analyses.”

DIETFITS-Perspectives

As you can imagine this study has led to quite an uproar and backlash from dedicated combatants in the macronutrient wars.

A reasoned summary and response from Andreas Eenfeldt, a low carb proponent can be found on his excellent low carb/keto Diet Doctor site here.

Eenfeldt concludes

If I’m allowed to speculate, the reason that we did not see any major additional benefit from low carb in this study is that the groups ended up so similar when it came to bad carbs. The low-fat group ended up eating fewer carbs too (!) and significantly less sugar, while the low-carb group ended with a somewhat weak low-carb diet, reporting 130 grams of carbs per day.

Eenfeldt emphasizes that low-fat diets never “win” these macronutrient dietary skirmishes:

On the whole, this study adds to the 57 earlier studies (RCTs) comparing low carb and low fat for weight loss.

From a standing of 29 wins for low carb, zero for low fat and 28 draws, we now have 29 wins for low carb and 29 draws. The wins for low fat stay at zero.

Larry Husten at Cardiobrief.org in his analysis of the study quotes a number of experts including Gary Taubes, the low carb pioneering journalist

Taubes speculates “that the weight loss may have been similar not because any diet works if you stick with it and cut calories (one possible interpretation) but because of what these diets had in common — avoid sugar, refined grains, processed foods. Whether the low-carb arm would have done even better had Gardner kept their carbohydrates low is something this study can’t say. (And Ornish [low-fat diet proponent] would probably say the same thing about fat consumption.)”

The low-fat or vegan disciples seem to have had a muted response to this study. I can’t find anything from John McDougal , Dean Ornish, Caldwell Esselstyn or Joel Fuhrman.

Readers feel free to leave comments which  link to relevant analysis from the low-fat proponents.

Dietfits-Perspective Of The Participants

Julia Volluz at Vox wrote a fascinating piece recently which involved interviewing some of the participants in this study.

She points out that although the average DIETFITS participant lost over 10 pounds, “Some people lost more than 60 pounds, and others gained more than 20 during the year.”

LOW_FAT_LOW_CARBS_DIETS1__1_

She obtained permission from the lead author, Christopher Gardner  and interviewed  “Dawn, Denis, Elizabeth*, and Todd — two low-fat dieters and two low-carb dieters — about their experiences of succeeding or faltering in trying to slim down”

LOW_FAT_LOW_CARBS_DIETS1

I highly recommend reading the entire article for details but Volluz concludes

And that leads us to one of the burning mysteries of diets: how to explain why some people fail where others succeed — or the extreme variation in responses. Right now, science doesn’t have compelling answers, but the unifying theme from the four study participants should be instructive: The particulars of their diets — how many carbs or how much fat they were eating — were almost afterthoughts. Instead, it was their jobs, life circumstances, and where they lived that nudged them toward better health or crashing.

DIETFITS-Importance of “Healthy” Diet

Most likely the success of both of these diets is due to the instruction that both groups received on following a “healthy” diet. This guidance is remarkably similar to what I advocate and is something that combatants in the diet wars ranging from paleo to vegan can agree on.

The JAMA paper only provides the description I listed above but Volluz adds that participants were instructed to:

… focus on whole, real foods that were mostly prepared at home when possible, and specifically included as many vegetables as possible, every day … choose lean grass-fed and pasture-raised animal foods as well as sustainable fish ... eliminate, as much as possible, processed food products, including those with added sugars, refined white flour products, or trans-fats … prepare as much of their own food as possible. …

Indeed, if you want to see a very detailed description of the instructional process for participants check out the very detailed description of the methods here.

Yours in Health,

-ACP

N.B. I was searching for a reasoned response to this study from the low fat camp and to my surprise came across this fascinating video featuring the lead author of the study, Christopher Gardner, on (no fat/vegan) John McDougal’s YouTube site. Gardner is clearly on the side of sustainable, local , ethical food consumption but to his credit, his research , publications and comments on DIETFITS don’t reveal this.

The Bad Food Bible: A Well-Written, Sensible and Science-Based Approach To Diet

The skeptical cardiologist has been searching for some time for a book on diet that he can recommend to his patients. While I can find books which have a lot of useful content, usually the books mix in some totally unsubstantiated advice with which I disagree.

I recently discovered a food/diet/nutrition book which with I almost completely agree. The author is Aaron Carroll,  a pediatrician, blogger on health care research (The incidental Economist) and a Professor of Pediatrics and Associate Dean for Research Mentoring at Indiana University School of Medicine.

He writes a regular column for the New York Times and covers various topics in health care. His articles are interesting,  very well written and researched and he often challenges accepted dogma.

Like the skeptical cardiologist, he approaches his topics from an unbiased perspective and utilizes a good understanding of the scientific technique along with a research background to bring fresh perspective to health-related topics.

Last last year he wrote a column, within which I found the following:

Studies of diets show that many of them succeed at first. But results slow, and often reverse over time. No one diet substantially outperforms another. The evidence does not favor any one greatly over any other.

That has not slowed experts from declaring otherwise. Doctors, weight-loss gurus, personal trainers and bloggers all push radically different opinions about what we should be eating, and why. We should eat the way cave men did. We should avoid gluten completely. We should eat only organic. No dairy. No fats. No meat. These different waves of advice push us in one direction, then another. More often than not, we end up right where we started, but with thinner wallets and thicker waistlines.

I couldn’t agree more with this assessment and as I surveyed the top diet books on Amazon recently, I saw one gimmicky, pseudoscientific  diet after another. From the Whole30 approach (which illogically  completely eliminates any beans and legumes, dairy products,  alcohol, all grains, and starchy vegetables like potatoes (see how absurd this diet is here)) to Dr. Gundry’s Plant Paradox (aka lectin is the new gluten (see here for James Hambling’s wonderful Atlantic article on the huckster’s latest attempt to scare you into buying his useless supplements).

It turns out Carroll published a useful book recently, The Bad Food Bible which critically examines diet and I agree with the vast majority of what is in it.

The first three chapters are on butter, meat, eggs and salt. His conclusions on how we should approach these 4 are similar to ones I have reached and written about on this site (see here for dairy, here for meat, here for eggs and here for salt).  Essentially, the message is that the dangers of these four foods have been exaggerated or nonexistent, and that consuming them in moderation is fine.

The remaining chapters cover topics I have pondered extensively,  but have not written about: including gluten, GMOs, alcohol, coffee, diet-soda and non-organic foods.

I agree with his assessments on these topics. Below, I’ll present his viewpoint along with some of my own thoughts in these areas.

Gluten

Carroll does a good job of providing a scientific, but lay-person friendly background to understanding the infrequent (1 of 141 Americans), but quite serious gluten-related disorder, celiac disease.

However, surveys show that up to one-third of Americans, the vast majority of whom don’t have celiac disease, are seeking “gluten-free” foods, convinced that this is a healthier way of eating. Carroll points out that there is little scientific support for this; there are some individuals who are sensitive to wheat/gluten, but these are rare.

He concludes:

“If you have celiac disease, you need to be on a gluten-free diet. If you have a proven wheat allergy, you need to avoid wheat. But if you think you have gluten sensitivity? You’d probably be better off putting your energy and your dollars toward a different diet. Simply put, most people who think they have gluten sensitivity just don’t.

I do agree with him that the “gluten-free” explosion of foods (gluten-free sales have doubled from 2010 to 2014) is not justified.

However, I must point out that my 92 year old father has recently discovered that he has something that resembles gluten sensitivity. About a year ago, he noted that about one hour after eating a sandwich he would feel very weak and develop abdominal discomfort/bloating. He began suspecting these symptoms were due to the bread and experimented with different bread types without any symptom relief.

Finally, he tried gluten-free bread and the symptoms resolved.

If you have engaged in this type of observation and experimentation on your self, and noted improved symptoms when not consuming gluten, then I think you’re justified in diagnosing gluten sensitivity, and by all means consider minimizing/avoiding wheat.

GMOS

Carroll begins his chapter on genetically modified organisms (GMOs) with a description of the droughts that plagued India in the 1960s and the efforts of Norman Borlaug to breed strains of wheat that were resistant to fungus and yielded more grain. By crossbreeding various strains of wheat he was able to develop a “semi-dwarf” strain that increased what was produced in Mexico by six-fold.

Despite the fact that numerous scientific and health organizations around the world have examined the evidence regarding the safety of genetically modified organisms (GMOs) and found them to be completely safe, there remains a public controversy on this topic. In fact a Pew Poll found that while 88% of AAAS scientists believe that GMOs are safe for human consumption, only 37% of the public do – a 51% gap, the largest in the survey.

This gap is largely due to an aggressive anti-GMO propaganda campaign by certain environmental groups and the organic food industry, a competitor which stands to profit from anti-GMO sentiments. There is also a certain amount of generic discomfort with a new and complex technology involving our food.

The National Academy of Sciences analyzed in detail the health effects of GMOs in 2016. Their report concludes:

While recognizing the inherent difficulty of detecting subtle or long-term effects in health or the environment, the study committee found no substantiated evidence of a difference in risks to human health between currently commercialized genetically engi-neered (GE) crops and conventionally bred crops, nor did it find conclusive cause-and-effect evidence of environmental problems from the GE crops. GE crops have generally had favorable economic outcomes for producers in early years of adoption, but enduring and widespread gains will depend on institutional support and access to profitable local and global markets, especially for resource-poor farmers

Carroll does a good job of looking at the GMO issue from all sides. He touches on environmental downsides related to herbicide-resistant GMO crops and the problems created by patenting GMO seeds, but asserts that “these are the result of imperfect farming and the laws that regular agribusiness, not of GMOS themselves.”

Ultimately, despite these concerns, I agree with Carroll’s conclusion that:

“Foods that contain GMOs aren’t inherently unhealthy, any more are  than foods that don’t contain them. The companies that are trying to see you foods by declaring them ‘GMO-free” are using the absence of GMOs to their advantage–not yours.”

Alcohol, Coffee, and Diet-Soda

Carroll does a good job of summarizing and analyzing the research for these three topics and reaches the same conclusions I have reached in regard to coffee, alcohol and diet-soda:

-alcohol in moderation lowers your risk of  dying, primarily by reducing cardiovascular death

-coffee, although widely perceived as unhealthy, is actually good for the vast majority of people

For those seeking more details a few quotes


on alcohol:

“Taken together, all of this evidence points to a few conclusions. First, the majority of the research suggests that moderate alcohol consumption is associated with decreased rates of cardiovascular disease, diabetes, and death. Second, it also seems to be associated with increased rates of some cancers (especially breast cancer), cirrhosis, chronic pancreatitis, and accidents, although this negative impact from alcohol seems to be smaller than its positive impact on cardiovascular health. Indeed, the gains in cardiovascular disease seem to outweigh the losses in all the other diseases combined. The most recent report of the USDA Scientific Advisory Panel agrees that “moderate alcohol consumption can be incorporated into the calorie limits of most healthy eating patterns.”

Keep in mind that moderate consumption is up to one drink per day for women, and two drinks for men (my apologies to women in general and the Eternal Fiancee’ of the Skeptical Cardiologist in particular) and be aware of what constitutes “one drink.”

Also keep in mind that any alcohol consumption raises the risk of atrial fibrillation (see here) and that if you have a cardiomyopathy caused by alcohol you should avoid it altogether.


on coffee:

“It’s time people stopped viewing coffee as something to be limited or avoided. It’s a completely reasonable part of a healthy diet, and it appears to have more potential benefits than almost any other beverage we consume.
Coffee is more than my favorite breakfast drink; it’s usually my breakfast, period. And I feel better about that now than ever before. It’s time we started treating coffee as the wonderful elixir it is, not the witch’s brew that C. W. Post made it out to be.”

Strangely enough, coffee is usually my breakfast as well (although I recommend against adding titanium oxide to your morning java).  Why am I not compelled to consume food in the morning?  Because breakfast is not the most important meal of the day and I don’t eat until I’m hungry.


on diet-soda:

Carroll notes that many Americans are convinced that artificial sweeteners are highly toxic:

“no article I’ve written has been met with as much anger and vitriol as the first piece I wrote on this subject for the New York Times, in July 2015, in which I admitted, “My wife and I limit our children’s consumption of soda to around four to five times a week. When we let them have soda, it’s . . . almost always sugar-free.”

He notes, as I have done, that added sugar is the real public enemy number one in our diets. He reviews the scientific studies that look at toxicity of the various artificial sweeteners and finds that they don’t convincingly prove any significant health effects in humans.

Some believe that artificial sweeteners contribute to obesity, but the only evidence supporting this idea comes from observational studies. For many reasons, we should not highly value observational studies but one factor, “reverse causation,” is highly likely to be present in studies of diet sodas. If diet soda consumption is associated with obesity, is it the cause, or do those who are obese tend to drink diet soda. Observational studies cannot answer this question but randomized studies can.

Carroll points out that:

the randomized controlled trials (which are almost always better and can show causality) showed that diet drinks significantly reduced weight, BMI, fat, and waist circumference.”

Simple Rules For Healthy Eating

Carroll concludes with some overall advice for healthy eating:

-Get as much of your nutrition as possible from a variety of completely unprocessed foods

-Eat lightly processed foods less often

-Eat heavily processed foods even less often

-Eat as much home-cooked food as possible, preparing it according to rules 1, 2, and 3

-Use salt and fats, including butter and oil, as needed in food preparation

-When you do eat out, try to eat at restaurants that follow the same rules

-Drink mostly water, but some alcohol, coffee, and other beverages are fine

-Treat all calorie-containing beverages as you would alcohol

-Eat with other people, especially people you care about, as often as possible

These are solid, albeit not shocking or book-selling, rules that  correspond closely to what I have adopted in my own diet.

In comparison to the bizarre advice from nutrition books which dominate the best-selling diet books, I found The Bad Food Bible to be a consistent, well-written, extensively researched, scientifically-based, unbiased guide to diet and can highly recommend it to my readers and patients.

Semibiblically Yours,

-ACP

Does Eating Saturated Fat Lower Your Risk of Stroke and Dying?: Humility and Conscience in Nutritional Guidelines

A study presented at the European Society of Cardiology  meetings in Barcelona and simultaneously published in The Lancet earlier this month caught the attention of many of my readers. Media headlines trumpeted  “Huge New Study Casts Doubt On Conventional Wisdom About Fat And Carbs” and “Pure Shakes Up Nutritional Field: Finds High Fat Intake Beneficial.”

Since I’ve been casting as much doubt as possible on the  conventional nutritional wisdom  to cut saturated fat, they reasoned, I should be overjoyed to see such results.

What Did the PURE Study Find?

The Prospective Urban Rural Epidemiology (PURE) study, involved more than 200 investigators who collected data on more than 135000 individuals from 18 countries across five continents for over 7 years.

There were three high-income (Canada, Sweden, and United Arab Emirates), 11 middle-income (Argentina, Brazil, Chile, China, Colombia, Iran, Malaysia, occupied Palestinian territory, Poland, South Africa, and Turkey) and four low-income countries (Bangladesh, India, Pakistan, and Zimbabwe)

This was the largest prospective observational study to assess the association of nutrients (estimated by food frequency questionnaires) with cardiovascular disease and mortality in low-income and middle-income populations,

The PURE team reported that:

Higher carbohydrate intake was associated with an increased risk of total mortality but not with CV disease or CV disease mortality.

This finding meshes well with one of my oft-repeated themes here, that added sugar is the major toxin in our diet (see here and here.)

Higher fat intake was associated with lower risk of total mortality.

Each type of fat (saturated, unsaturated, mono unsaturated ) was associated with about the same lower risk of total mortality. 

 

These findings are consistent with my observations that it is becoming increasingly clear that cutting back on  fat and saturated fat as the AHA and the Dietary Guidelines for Americans have been telling you to do for 30 years is not universally helpful (see here and  here ).

When you process the fat out of dairy and eliminate meat from your diet although your LDL (“bad”) cholesterol drops a little your overall cholesterol (atherogenic lipid) profile doesn’t improve (see here).

Another paper from the PURE study shows this nicely and concluded:

Our data are at odds with current recommendations to reduce total fat and saturated fats. Reducing saturated fatty acid intake and replacing it with carbohydrate has an adverse effect on blood lipids. Substituting saturated fatty acids with unsaturated fats might improve some risk markers, but might worsen others. Simulations suggest that ApoB-to-ApoA1 ratio probably provides the best overall indication of the effect of saturated fatty acids on cardiovascular disease risk among the markers tested. Focusing on a single lipid marker such as LDL cholesterol alone does not capture the net clinical effects of nutrients on cardiovascular risk.

Further findings from PURE:

-Higher saturated fat intake was associated with a lower risk of stroke

-There was no association between total fat or saturated fat or unsaturated fat with risk of heart attack or dying from heart disease.

Given that most people still believe that saturated fat causes heart disease and are instructed by most national dietary guidelines to cut out animal and dairy fat this does indeed suggest that

Global dietary guidelines should be reconsidered …”

Amen!

Because the focus of dietary guidelines on reducing total and saturated fatty acid intake “is largely based on selective emphasis on some observation and clinical data despite the existence of several randomizesed trials and observational studies that do not support these conclusions.”

Pesky Confounding Factors

We cannot infer causality from PURE because like all obervational studies, the investigators do not have control over all the factors influencing outcomes. These confounding factors are legion in a study that is casting such a broad net across different countries with markedly different lifestyles and socioeconomic status.

The investigators did the best job they could taking into account household wealth and income, education, urban versus rural location and the effects of study centre on the outcomes.

In an accompanying editorial, Christopher E Ramsden and Anthony F Domenichiello, prominent NIH researchers,  ask:

“Is PURE less confounded by conscientiousness than observational studies done in Europe and North American countries?

 

“Conscientiousness is among the best predictors of longevity. For example, in a Japanese population, highly and moderately conscientious individuals had 54% and 50% lower mortality, respectively, compared with the least conscientious tertile.”

“Conscientious individuals exhibit numerous health-related behaviours ranging from adherence to physicians’ recommendations and medication regimens, to better sleep habits, to less alcohol and substance misuse. Importantly, conscientious individuals tend to eat more recommended foods and fewer restricted foods.Since individuals in European and North American populations have, for many decades, received in influential diet recommendations, protective associations attributed to nutrients in studies of these populations are likely confounded by numerous other healthy behaviours. Because many of the populations included in PURE are less exposed to in influential diet recommendations, the present findings are perhaps less likely to be confounded by conscientiousness.”

It is this pesky conscientiousness factor (and other unmeasured confounding variables) which limit the confidence in any conclusions we can make from observational studies.

I agree wholeheartedly with the editorial’s conclusions:

Initial PURE findings challenge conventional diet–disease tenets that are largely based on observational associations in European and North American populations, adding to the uncertainty about what constitutes a healthy diet. This uncertainty is likely to prevail until well designed randomised controlled trials are done. Until then, the best medicine for the nutrition field is a healthy dose of humility.

 

Ah, if only the field of nutrition had been injected with a healthy dose of humility and a nagging conscience thirty years ago when its experts declared confidently that high dietary fat and cholesterol consumption was the cause of heart disease.!

Current nutritional experts and the guidelines they write will  benefit from a keen awareness of the unintended consequences of recommendations which they make based on weak and insufficient evidence  because such recommendations influence the food choices  (and thereby the quality of life and the mechanisms of death) of hundreds of millions of people.

PUREly Yours,

ACP

Dear Kaldi’s, Please Stop Serving Candied Bacon: It Is A Health And Gastronomic Abomination

The skeptical cardiologist enjoys bacon (in moderation), often with quiche, despite the fact that The Who (World Health Organization, not the band that John Entwhistle played for) classifies it as a carcinogen.

Enjoying bacon has become more difficult these days due to the development of a most disturbing fad: the adulteration of bacon  with sugar in some way, shape, or form.

The Eternal Fiancee’ recently ordered a bacon, egg and cheddar on croissant sandwich at my favorite St. Louis coffee spot, Kaldi’s when to our horror, candied bacon was served.

An inquiry at the serving counter  revealed that Kaldi’s only serves candied bacon; you can’t get any that hasn’t been turned into a monstrosity!

I find candied bacon to be an abomination.  All I can taste is sugar and any subtleties of the bacon or its preparation are eclipsed by the saccharine bulk of the sugar.

If this graphic (from my fitness pal.org) is to be believed, the three slices in her sandwich added 40 grams of sugar. This is the equivalent of 10 teaspoons of sugar and the amount of sugar in a bottle of Coke.

 

 

 

 

Readers of this blog know that I consider sugar, not fat, as the major toxin in our diet, contributing to obesity, diabetes and ultimately heart attack and stroke. I’ve also pointed out that huge amounts of added sugar are hidden in smoothiescoffee drinks, and non fat yogurt.

The massive amount of sugar in this candied bacon is not exactly stealth: you can tell it from the first bite. However, there is nothing in the description of the croissant sandwich that alerts you to the fact that your bacon will be transmogrified into candy.

Serving only candied bacon in my opinion is the equivalent of only serving coffee that has had sugar added to it and Kaldi’s should know better.

Kaldi’s is proud of their community commitment which includes support for the Juvenile Diabetes Research Foundation. What about supporting healthier food choices (with no added sugar)  for kids so they are less likely to get diabetes and if they have diabetes will be  less likely to be poorly controlled?

I implore Kaldi’s to stop this madness.

Antisucroporcinely Yours,

-ACP

N.B. The Eternal Fiancee’ just tried to order a smoothie at the Clayton Kaldi’s and discovered to her horror that their peanut butter contains hydrogenated oils and added sugar. Yikes!

Fructose and the Ubiquity of Added Sugar

Since realizing that sugar, and not fat, was the major problem in the modern Western diet, The Skeptical Cardiologist has been ratcheting down how much sugar he consumes to the smallest possible amount.

This has lowered what I like to call my “sugarstat,” and has made me exquisitely sensitive to the presence of added sugar in foods.

With this sensitivity comes the heightened realization that added sugar is everywhere.

The obvious sources are soft drinks and other sweetened beverages, candy, cakes, pies, cookies, donuts and fruit juices. Once you mostly eliminate such things from your diet you become aware of the “background” levels of added sugar in other foods.

For example, when I consume what many Americans probably perceive as a “healthy” granola bar (from even the most natural or organic of manufacturers), all I can taste is a sickly sugar taste overwhelming all the other ingredients.

Low-fat yogurt (which I have compared unfavorably to a Snickers Bar here) tastes like pure sugar mixed with odd chemicals and a vague dairy flavor.

Seemingly healthy sushi tastes too sweet to me as it turns out to have lots of sugar mixed in  the rice and the popular eel sauce is mostly made up of sugar.

Most annoying  is the current trend for restaurants to put a “balsamic glaze” loaded with sugar on perfectly good vegetables like brussel sprouts, ruining them for me.

Fructose and Processed Foods

A review article in the Mayo Clinic Proceedings (1) this month presents the case for fructose (from glucose and high-fructose corn syrup) being the major cause of our obesity and diabetes epidemics and thus, the major contributor to cardiovascular disease in the US.

Fructose is a monosaccharide that combines with the monosaccharide glucose to form sucrose, which is what most people recognize as sugar.

Processed foods commonly contain a lot of added fructose-containing sugar but also, increasingly they contain high fructose corn syrup (HFCS) which contains up to 65% fructose.

Large intake of fructose goes hand in hand with consumption of processed foods. Approximately 75% of all foods and beverages in the US contain added sugars. Consumption of added sugar by Americans increased from 4 lbs per person per year to 120 lbs per person per year between 1776 and 1994.

Thanks to a dramatic increase in sugar-sweetened beverages, American teenagers consume about 72 grams of fructose daily.

There are a substantial amount of observational, short-term basic science, and clinical trial data suggesting that all this added sugar, especially fructose, are posing a serious public health problem.

The article presents these data in detail and I’ll summarize the major points as follows:

  1. Fructose is the likely component of sucrose and HFCS that promotes insulin resistance.
  2. In animals and humans, replacement of starch (chains of glucose) with sucrose or fructose causes increase glucose and insulin levels and reduced insulin sensitivity.
  3. Fructose stimulates epigenetic changes and metabolic alterations that shunt calories into storage depots in abdominal fat cells.

In simpler language, fructose promotes abdominal fat build-up and makes you more likely to develop type 2 diabetes.

Fruits and Fructose

I’m sure many of you are thinking, “but fructose is the major sugar in fruit, should I stop eating fruit?”

The answer is NO! The fructose in fruit is not highly concentrated. Fructose makes up 1% of the weight of a pear for example. It is combined with all of the good things, including fiber and phytonutrients and vitamins, that make fruit good for you.

Eliminating added fructose (sugar and HFCS) is by far the simplest thing you can do diet wise to improve your health. If you avoid added fructose, you will be cutting out a lot of the processed foods and sugar-sweetened beverages which have no nutritional value but contribute to obesity and diabetes.

Fructose as Toxin

preserves
Real fruit (right) and “Just Fruit Spread” (left). Note the attempts to make the spread appear healthy by announcing that it is “non-GMO”, glutan-free, “organic” and “perfectly sweetened with fair trade cane sugar”. Cane juice is added sugar .

Robert Lustig, a pediatric endocrinologist has talked and written extensively about fructose as a “toxin.” You can watch him here. He’s also published a lot of books on the topic including one which identifies the 56 names under which sugar masquerades.

It’s probably not worth buying that book, but keep in mind that agave and evaporated cane juice are just different forms of sugar. Makers of organic and “natural” foods are   as guilty as food industry giants at adding sugar, but they try to pretend that “natural” sources of sugar are somehow better for you.

I don’t think the science on fructose is totally settled, however, and another recent review (from scientists not funded by the food industry) concluded:

“current evidence on the metabolic effects of fructose, as consumed by the majority of populations, is insufficient to demonstrate such a role in metabolic diseases and the global obesity epidemic”

Skeptically Yours,

Anthony C. Pearson, MD, FACC

1. Added Fructose: A Principal Driver of Type 2 Diabetes Mellitus and Its Consequences. Mayo Clin Proc. 2015:90(3);372-381. DiNicolantonio, JJ, O’Keefe, JH and Lucan SC

Smoothies: Kings of Sugar Masquerading As Healthy Food Choice

I have had a vague interaction with smoothies in the past, but after a recent jam session with my bassist daughter and drummer son, my daughter enthusiastically recommended we get a smoothie. “Smoothie” was entered into the Apple map app and a remarkable number of establishments serving this concoction popped up.

Smoothie sales have taken off in the last decade as consumers are apparently seeking healthier alternatives to carbonated beverages.

This was my first experience with Smoothie King which is the biggest and oldest chain of smoothie purveyors. According to their web site:

Since Steve Kuhnau created the first Smoothie Bar in 1973, Smoothie King has grown to over 650 locations across three continents. From the US to the Republic of Korea, Singapore and the Cayman Islands, our purpose continues to impact millions of lives around the globe.

Our quest is simple: Make living a healthier more active lifestyle delicious and nutritious. Whether you’re trying to lose a few pounds, have a little more energy at the end of the day or simply feel better about your diet, each and every Smoothie we make is blended for a specific purpose. Which is why we call them “Smoothies With A Purpose.”

This sounds spectacularly good: who wouldn’t want to lose a few pounds, have more energy at the end of the day and feel better about their diet.

Smoothie-King-New-Store-Design-interiorThe Smoothie King store was disturbingly sterile with an intense corporate feeling and had a bewildering array of choices. I could choose from Fitness Blends, Energy Blends, Slim Blends, Wellness Blends or Take a Break Blends.

 

There are 17 “Slim Blends” to choose from. The Angel Food  (“treat your body like an angel”(I have no idea what that means)) Slim Blend contains 350 calories, 84 grams of carbohydrates, 75 grams of sugar, 4 grams of protein, and 6 grams of fiber. This comes from strawberries (I saw no real strawberries behind the counter),bananas, non-fat milk (when I asked about getting whole milk the girl behind the counter told me that they didn’t even use real non-fat milk just a powder), vanilla, turbinado (fancy and deceptive word for brown sugar) and soy protein.

What’s wrong with this? A smoothie from SmoothieKing marketed as a Slim Blend contains 75 grams of sugar, the equivalent of 19 cubes of sugar. There only 39 grams of sugar in a 12 ounce coca-cola thus the small 20 oz “Slim Blend” contains the equivalent of two cans of coca-cola in sugar. There may be some useful nutrients in this monstrosity but predominantly you are getting loads of sugar in a highly concentrated form.

As I’ve pointed out here and here, there is reason to believe that sugar contributes more to obesity and heart disease than fat. Its hard to understand how this Slim Blend would contribute to weight loss in any way. It is just another stealth dessert similar to what Starbucks promotes as I’ve discussed here. What the food industry has done to smoothies is eerily similar to what happened to yogurt which I call the no fat  yogurt scam.

Most people have figured out for good weight control and health they should avoid sodas and sugar-sweetened beverages (even my 19 year old daughter has) but smoothies are masquerading as healthy choices for slimming, for fitness or wellness when they are (in the case of ones from SmoothieKing and presumably most similar chains) an absolutely horrible dietary choice.

What we have here is the classic food industry approach to marketing: Take real food ingredients like fruits, which are healthy choices when consumed in their original state, process  them, industrialize them, add sugar and promote them as healthier dietary choices.

Add in the veneer of promoting fitness or weight loss or wellness by adding magically powerful elixirs or powders and  the duped public will line up and sales will skyrocket. Unfortunately, despite claims of health benefits, consumers will end up less healthy.