The skeptical cardiologist this morning was greeted by headlines announcing that an international panel of 14 unbiased researchers had concluded that it was OK for humans to continue eating red meat and processed meat at current levels.
The startling news was a reversal of what the Dietary Guidelines for Americans, the AHA and the American Cancer Society have been telling us for years and threw the nutritional world into a tizzy. The bottom line recommendation, written in language suggesting a lack of certainty in the evidence and lack of confidence in the advice reads as follows:
The panel suggests that adults continue current unprocessed red meat consumption (weak recommendation, low-certainty evidence). Similarly, the panel suggests adults continue current processed meat consumption (weak recommendation, low-certainty evidence).
Volluz does her typically excellent job of explaining the science in a balanced way and includes some of the prominent voices who are outraged by the publication.
As I’ve pointed out (here and here and here) the science behind most nutritional recommendations is weak and often public health authorities make sweeping dietary recommendations that aren’t justified.
We are making gradual progress in rolling back bans on some healthy food, like eggs but unjustified bans on other healthy foods like full-fat yogurt and coconut oil persist.
When it comes to red meat consumption the systematic analyses reveal mild associations with poor health outcomes but these associations don’t prove causality and could easily be due to confounding factors or poor input data.
Thus, if you want to cut back your red meat consumption on the chance that these associations are truly reflective of causation go ahead. Especially if you have ethical or environmental concerns about production of red meat.
Just keep in mind that the calories you cut from less meat consumption should be replaced by more healthy nutrient-dense foods like non-starchy vegetables, nuts, dairy fat, avocado and olive oil and not by low quality carbs and ultra-processed food or you may be doing more harm than good.
Most Americans take it for granted that if they want to lower their risk of heart disease they should switch from eating red meat to eating chicken. As a result, US and world-wide poultry consumption has tripled since 1980 and surpassed beef consumption.
The switch from beef and pork to chicken has been driven in large part by widespread recommendations to consume less saturated fat and cholesterol.
For example the American Heart Association (AHA) (in its typically misguided) way says:
In general, red meats (beef, pork and lamb) have more cholesterol and saturated (bad) fat than chicken, fish and vegetable proteins such as beans. Cholesterol and saturated fat can raise your blood cholesterol and make heart disease worse. Chicken and fish have less saturated fat than most red meat.
Instead of listing any facts or studies relevant to your cardiovascular health the AHA choses to repeat the meaningless first sentence again in the last sentence (beef, pork and lamb have more cholesterol and saturated fat than chicken, fish and… beans becomes chicken and fish have less saturated fat than most red meat.)
At LIvestrong the claim is repeated that by choosing skinless chicken breasts over red meat your bad cholesterol (and risk of heart disease) will be lowered. Furthermore, Livestrong repeats the unsubstantiated trope that you will better manage your weight by eating low fat food.
A chicken breast is relatively low in saturated fat compared to many protein alternatives, especially when the skin is removed. By substituting chicken for higher-fat cuts of meat, you will lower your risk of developing heart disease by reducing your LDL, or “bad” cholesterol. Eating lower-fat alternatives will also help you maintain a healthy weight. Grilling, broiling and baking are great cooking methods to keep the fat content at its lowest.
When we carefully examine the evidence, however, there is no scientific support for either of these claims-switching to chicken from beef has never been shown to reduce your risk of heart disease. In fact, more recent studies show the switch won’t improve biomarkers that predict long-term risk of cardiovascular disease.
And switching to chicken from beef does not improve weight management.
Changes in the fasting lipid profile were not significantly different with beef consumption compared with those with poultry and/or fish consumption. Inclusion of lean beef in the diet increases the variety of available food choices, which may improve long-term adherence with dietary recommendations for lipid management.
support that the consumption of ≥0.5 compared with <0.5 servings of total red meat/d does not influence blood lipids, lipoproteins, and/or blood pressures, which are clinically relevant CVD risk factors. These results are generalizable across a variety of populations, dietary patterns, and types of red meat.
Eating Fat Doesn’t Make You Fat
Once again I feel like I’m beating a dead horse here but it bears repeating- the concept that switching from a high fat food item to a low fat item will cause weight loss is totally false.
There are actually numerous studies showing that there is no difference between chicken and beef consumption on weight or body fat:
1. Melanson et al. conducted a 12-week randomised, controlled trial of overweight women on an energy restricted diet with either lean beef or chicken as the major protein source along with moderate exercise. There was no difference in weight loss or % body fat or blood lipid profiles between the patients on the beef or chicken diet.
2., Mahon et al. compared consumption of lean beef or chicken as the primary protein source over 12 weeks in a hypocaloric diet in 61 obese females. There was no difference between the chicken or beef eaters in the amount of weight loss, fat loss or drop in LDL (bad) cholesterol.
Finally, here’s a 2014 RCT study of 49 obese adults who were randomly assigned to consume up to 1 kg/week of pork, chicken or beef, in an otherwise unrestricted diet for three months, followed by two further three month periods consuming each of the alternative meat options.
There was no difference in BMI or any other marker of adiposity between consumption of pork, beef and chicken diets. Similarly there were no differences in energy or nutrient intakes between diets
Vegetarians Uniformly Condemn Chickens As Unhealthy
It’s interesting that a Google search for the healthiness of chicken versus beef yields the standard dietary dogma from mainstream nutritional sources like the AHA or the American Academy of Nutrition and Dietetics but also a large number of sites that want to convince you of how unhealthy chicken is.
These sites are vegan or vegetarian sites such as plantbasednews.org which lists these six “shocking” reasons why you should stop eating chicken:
At least one of the reasons is clearly documented:
Several of the reasons are more ethical/moral in nature and I leave it up to my readers to decide how important these are to them.
-“The poultry industry has a devastating impact on the environment” related to pollution from factory farms.
-“chickens are intelligent animals”
-“The slaughter of birds is horrifying”
The Guardian.com has a good article on the horror of factory farm chicken raising entitled “If consumers knew how farmed chickens were raised they might never eat their meat again” which I recommend to those who are not already familiar with the conditions in which 99.9% of broilers are raised.
One “shocking reason” listed by plantbasednews appears untrue-“chickens are stuffed with cancer-causing arsenic” The FDA in 2017 indicates that the animal drug which raised arsenic levels in chicken livers (3-Nitro) had been withdrawn from the market.
Bottom Line-No Universal Health Reason To Switch From Red Meat To Chicken
There are many other factors which go into the overall effect of beef and chicken on our bodies. For one thing, how the meat is prepared and what accompanies it will have a much greater influence on health than whether it is chicken or red meat.
It’s time to rid America of the idea that chicken is healthier than beef-it is not and has never been supported by good scientific studies.
If you’ve been diagnosed with heart disease don’t assume you can only eat skinless chicken breasts as meat for the rest of your life.
The change from beef to chicken definitely won’t help you lose weight.
And it won’t reduce your risk of heart attack or stroke.
Beef in moderation can definitely be part of a heart healthy diet and a weight loss diet. Just be sure to eat plenty of fresh vegetables, nuts, fresh fruit, legumes, and fish along with your red meat. and minimize processed foods, added sugars and empty carbs.
Since the skeptical cardiologist has in previous posts waxed poetic on Jambon Iberico and beef brisket, I feel compelled to comment on this report.
We’ve been through this before and this announcement is not based on any new and striking data.
It is based on reviewing a lot of observational studies from the past decades. It is very important to understand that observational studies do not establish cause and effect, they only look at associations.
GaryTaubes has written eloquently on this in 2012:
“It’s this compliance effect that makes these observational studies the equivalent of conventional wisdom-confirmation machines. Our public health authorities were doling out pretty much the same dietary advice in the 1970s and 1980s, when these observational studies were starting up, as they are now. The conventional health-conscious wisdom of the era had it that we should eat less fat and saturated fat, and so less red meat, which also was supposed to cause colon cancer, less processed meat (those damn nitrates) and more fruits and vegetables and whole grains, etc. And so the people who are studied in the cohorts could be divided into two groups: those who complied with this advice — the Girl Scouts, as Avorn put it — and those who didn’t.
Now when we’re looking at the subjects who avoided red meat and processed meat and comparing them to the subjects who ate them in quantity, we can think of it as effectively comparing the Girl Scouts to the non-Girl Scouts, the compliers to the conventional wisdom to the non-compliers. And the compliance effect tells us right there that we should see an association — that the Girl Scouts should appear to be healthier. Significantly healthier. Actually they should be even healthier than Willet et al. are now reporting, which suggests that there’s something else working against them (not eating enough red meat?). In other words, the people who avoided red meat and processed meats were the ones who fundamentally cared about their health and had the energy (and maybe the health) to act on it. And the people who ate a lot of red meat and processed meat in the 1980s and 1990s were the ones who didn’t.
Here’s another way to look at it: let’s say we wanted to identify markers of people who were too poor or too ignorant to behave in a health conscious manner in the 1980s and 1990s or just didn’t, if you’ll pardon the scatological terminology, give a sh*t. Well, we might look at people who continued to eat a lot of bacon and red meat after Time magazine ran this cover image in 1984 — “Cholesterol, and now the bad news”. I’m going to use myself as an example here, realizing it’s always dangerous and I’m probably an extreme case. But I lived in LA in the 1990s where health conscious behavior was and is the norm, and I’d bet that I didn’t have more than half a dozen servings of bacon or more than two steaks a year through the 1990s. It was all skinless chicken breasts and fish and way too much pasta and cereal (oatmeal or some other non-fat grain) and thousands upon thousands of egg whites without the yolks. Because that’s what I thought was healthy.
So when we compare people who ate a lot of meat and processed meat in this period to those who were effectively vegetarians, we’re comparing people who are inherently incomparable. We’re comparing health conscious compliers to non-compliers; people who cared about their health and had the income and energy to do something about it and people who didn’t. And the compliers will almost always appear to be healthier in these cohorts because of the compliance effect if nothing else. No amount of “correcting” for BMI and blood pressure, smoking status, etc. can correct for this compliance effect, which is the product of all these health conscious behaviors that can’t be measured, or just haven’t been measured. “
For more discussion on the weakness of observational epidemiology upon which this WHO pronouncement rests see here
Even if we were to accept the concept that red meat is a carcinogen, this does not mean everyone should end red meat consumption.
For perspective I would suggest reading this post from cancer researchUK. Although the WHO classifies both smoking and processed red meat as carcinogens they are not in the same ball park in terms of overall cancers and deaths caused as this infographic demonstrates.
A one pack a day cigarette smoker has 20 times the risk of developing small cell lung cancer as a non-smoker.
A high frequency meat eater, on the other hand has a 1.17 time increased risk as the lowest frequency meat eater.
As cancerUK put it:
“We know that, out of every 1000 people in the UK, about 61 will develop bowel cancer at some point in their lives. Those who eat the lowest amount of processed meat are likely to have a lower lifetime risk than the rest of the population (about 56 cases per 1000 low meat-eaters).
If this is correct, the WCRF’s analysis suggests that, among 1000 people who eat the most processed meat, you’d expect 66 to develop bowel cancer at some point in their lives – 10 more than the group who eat the least processed meat.”
So keep in mind
Weak associations between red meat and processed red meat and cancer or heart disease do not establish that one causes the other. Such studies are good for generating hypotheses that then need to be tested.
If processed meats are a carcinogen they are a far, far less important one than cigarette smoking.
NB.From the press release:
“Red meat refers to all types of mammalian muscle meat, such as beef, veal, pork, lamb, mutton, horse, and goat.
Processed meat refers to meat that has been transformed through salting, curing, fermentation, smoking, or other processes to enhance flavour or improve preservation. Most processed meats contain pork or beef, but processed meats may also contain other red meats, poultry, offal, or meat by-products such as blood.
Examples of processed meat include hot dogs (frankfurters), ham, sausages, corned beef, and biltong or beef jerky as well as canned meat and meat-based preparations and sauces.
A summary of the final evaluations is available online in The Lancet Oncology, and the detailed assessments will be published as Volume 114 of the IARC Monographs.”