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    Protein:  Misinformation from doctors and dietitians

    by Michael Bluejay • Last update: January 2023

    You'd think that you could always trust what doctors and dietitians tell you about protein.  Unfortunately, many health professionals are shockingly misinformed, pushing urban legends about protein that were disproved decades ago.  As John McDougall, M.D. puts it:

    The Nutrition Committee of the American Heart Association, scientists from the Human Nutrition Research Center and Medical School at Tufts University, and registered dietitians, research nutritionists and physicians of Northwestern University, and the Harvard School of Public Health are just a few examples of "experts" you look to for advice who have the protein story wrong.  Consequences of their shortfall are as grave as a lifetime of sickness and obesity, and premature death, for innocent people.  These professionals must be held accountable. (source)

    First let's review a couple of simple concepts, explained in detail (and with plenty of evidence) on the main protein page:

    1. Besides fruit, all whole plant foods have plenty of protein.
    2. It's also complete protein — no special combining is necessary.
    Confirming this is trivial.  The USDA nutrient database has been public for decades, and the figures there can be compared to actual protein needs (such as in the WHO's protein report).  But that's apparently too much for some doctors and dietitians.  What's more, they're generally not receptive to looking at the actual figures when they're presented to them.  Besides the examples cited by Dr. McDougall, here are some more recent ones.


    Laura Burak, MS, RD • Kristeen Cherney, PhD • Lynn Grieger RDN, CDCES

    An online article by Dr. Cherney, and reviewed by Ms. Grieger, quotes Ms. Burak as saying:  "Oatmeal is a carbohydrate and contains little to no protein or fat, so it is digested more quickly than these macronutrients, which can lead to blood sugar swings...."

    It's amazing how many things she got wrong in a single sentence fragment.  In reality:

    1. Oatmeal is not "a carbohydrate".
    2. Oatmeal does not contain "little to no protein or fat".
    3. Oatmeal does not "lead to blood sugar swings".

    Let's take these one at a time.

    First oatmeal is not "a carbohydrate", i.e., all carbs.  Like almost all foods, it contains significant amounts of carbohydrate, protein, and fat.  As per the USDA database, it's about 68% carbs, 14% protein, and 18% fat.  That concentration of protein and fat is far from trivial.  In fact, the protein levels are about double the official recommendations, and the amount of fat is actually quite a bit higher than most other whole plant foods.

    Second, rather than starches screwing up your blood sugar, it's the exact opposite:  Starches cure diabetes.  What the science says: "Oatmeal significantly reduced the acute postprandial glucose and insulin responses compared with the control meal. The present study has revealed a beneficial effect of oats intake on glucose control and lipid profiles...."  No surprise, because this kind of information has been extant in the medical literature for decades.  Dr. John McDougall ran a clinic for 30 years at which he solved patients' blood sugar problems by feeding them a diet based on starches such as oatmeal.  A friend of mine with diabetes tried eating nothing but sweet potatoes (mostly starch) for three days.  His fasting blood glucose dropped a whopping 68 points.


    Katriny Ikbal, M.D.


    I visited her in July 2021 when I was looking for a primary care physician.  After asking what I eat, she followed up with, "Where do you get your protein?"  She also proceeded to (mistakenly) insist that it's necessary to combine plant foods to make a complete protein.  What's more shocking about Dr. Ikbal's latching onto these urban legends is that her undergraduate degree is in nutrition.


    ConsumerLab by Todd Cooperman, M.D.


    Dr. Cooperman's ConsumerLab touts milk proteins as complete as though plant foods are not:
    1. "[W]hey is most popular as it is a complete protein...."
    2. "Whey is a 'complete' protein, meaning that it contains all the essential amino acids...."
    3. "The other milk protein, casein, is also a 'complete' protein..."
    In fact, vegetables, grains, and beans also contain all the essential amino acids, in excess of human need.

    Elsewhere, ConsumerLab does identify some plant proteins as complete, which (wrongly) suggests that most plant proteins aren't:
    1. "Soy is considered a complete protein."  (By the way, it's not just "considered" a complete protein, it is.)
    2. "[W]hole-grain rice...contains all of the essential amino acids...."
    3. "Pea protein...is a complete protein...."
    4. "[O]ne of the main proteins in hemp is albumen, which...contains all of the essential amino acids."
    In fact, common vegetables, grains, and beans are all typically complete proteins.  Even tomatoes, even celery, even iceberg lettuce.

    ConsumerLab also misleads by not providing figures for context.  It says, "Whey protein is believed to be digested...more completely than soy protein."  In reality, whey protein's PDCAAS score is 1.00 while soy's is 0.91, not a massive difference.  In addition, PDCAAS is a poor measure anyway because it assumes that a person eats only one food, and gets zero amino acids from other foods.  In addition, the very design of PDCAAS means that it assigns poorer scores to plant foods even though they contain all the amino acids in excess of human need.

    Finally, ConsumerLab says:

    "Soy protein...contains little of the sulfur-containing amino acid methionine.  This deficiency in methionine is not a problem in normal nutrition for adults and children."

    This is contradictory.  Soy either has a "deficiency" in methionine, or the amount of methionine in soy is "not a problem", not both.  In fact, soy does contain more methionine than humans need, so it's wrong to label its methionine content as deficient.  (Methionine requirement is 30 mg per kg of body weight per day per WHO, or 2.5 g/d for a 181 lb. person, while a soybean-only diet would supply about 3.8 g/d according to USDA, or 52% more than one actually needs.  Some "deficiency".)

    A month after I notified ConsumerLab of these issues, all the misleading info remains in their article.


    ConsumerLab, round 2

    ConsumerLab is at it again, this time in an article which says that levels of acrylamide (a cancer-causing substance) can be reduced by eating "a source of protein" such as milk, eggs, or beefsteak.  This is two big blunders in one.

    First, the phrase "a source of protein" is a misnomer, since all unrefined plant foods contain copious protein, and nearly all of them in excess of what humans actually need.  By saying that only animal foods are a "source of protein", CL perpetuated the myth that plant foods are devoid of protein, when the reality is quite the opposite.  Accurate phrasing to refer to the animal foods would be "high protein foods".  That is true: animal foods generally have more protein than plant foods, even though plant foods alone supply more protein than we need.  To its credit, when I alerted CL about this, they changed "a source of protein" to "protein-rich foods".

    But they wouldn't fix the second problem, which is that CL's paragraph is completely devoid of important context.  While high-protein animal foods might reduce acrylamide, those foods have also been conclusively linked to diseases that kill Americans in far greater numbers than acrylamide-induced cancer, such as other cancers, heart disease, and diabetes.  People who eat more animal protein in order to lower acrylamide levels would, ironically, almost certainly be increasing their risk of more serious disease and earlier death.  It's like CL telling us that a study showed that walking around and firing a gun indiscriminately reduces diabetes mortality, and failing to mention that the reason is that people who do that tend to die young from getting shot by the police before they can develop advanced diabetes.


    ConsumerLab, round 3

    ConsumerLab touts plant-based milks "rival regular milk" with their protein content.  Thus CL commits the "more is better" fallacy.  When almost everyone gets more protein than they need, the high protein content of certain foods is not a benefit.

    With this entry, I'll likely stop calling out problems at ConsumerLab, because pretty much every time they write about protein, they get it wrong.


    Catherine Perez, R.D.

    In a CNBC article, registered dietitian repeats the myth that vegans have to make a special effort to get enough protein.  Dietitians who repeat that myth are a dime a dozen, but in this particular case it's even more unfortunate for a couple of reasons:  Perez promotes plant-based diets (and therefore really ought to know better), and she ignored my email in which I referred her to my protein article which shows, using official sources, how it's nearly impossible to not get enough protein.