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
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).
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.