Top 5 Misconceptions About Food: A Doctor’s Daily Experience by Michelle McMacken, M.D.

As a primary care doctor, I spend my days taking care of patients with diabetes, high blood pressure, high cholesterol, heart disease, and obesity. I also see “healthy” patients whose eating habits are starting them on the road to a future filled with doctor’s appointments and hospital visits.

I enjoy reminding my patients that their fork can be more powerful than my prescription pad when it comes to preventing and reversing chronic diseases. This conversation usually uncovers some common misconceptions about food and nutrition. Here are five myths that I hear almost every day, among patients and colleagues alike:

1. “I need to eat more protein.”

Many people don’t realize that the average American consumes more than twice the Recommended Dietary Allowance (RDA) of protein, most of it from animal products. 1,2Unfortunately, animal-based proteins have been shown to promote faster growth, not only of normal cells but of cancer cells, and have been linked to a variety of cancers as well as heart disease, diabetes, Alzheimer’s disease, and kidney stones.3,4

Plant foods contain plenty of protein, and a whole-foods, plant-based diet actually provides exactly what’s recommended in terms of protein requirements – about 8-10% of total daily calories from protein.  This happens naturally when people eat a diet of diverse, whole plant foods – there is no need to count grams of protein!  And unlike animal proteins, plant proteins from whole foods are not associated with cancer or other chronic diseases.  In fact, these foods actually prevent many of the diseases we see today!

2. “I need to drink milk to have strong bones.”

Many people equate dairy with calcium, strong bones, and the prevention of osteoporosis (low bone density). Generations of advertising slogans have perpetuated this idea. However, dairy isn’t the answer here. Studies show that dairy products may actually increase the risk of fractures related to osteoporosis!5-7

The biological purpose of cow’s milk is to support the rapid growth of a calf. Humans have no nutritional or medical need to consume the milk of cows or any other nonhuman species. Cow’s milk has significant levels of female hormones, and usually contains antibiotics, pesticides, saturated fat, and cholesterol — substances that definitely do NOT do a body good! Dairy has been specifically linked with prostate, ovarian, and uterine cancer, as well as heart disease and early death.7-13

The best sources of calcium come from the earth, in foods such as kale, broccoli, bok choy, and Brussels sprouts. As a bonus, these vegetables are high in vitamin K, which is also important for strong bones. Beans may be an especially good source of calcium, because they are also high in phytates, antioxidant compounds that may enhance mineral absorption14 (despite common perception to the contrary) and thus protect bone density.15 Many brands of soy milk, almond milk, orange juice, and tofu are fortified with calcium and vitamin D, just as cow’s milk is artificially fortified with these nutrients. However, there is no need to specifically target calcium sources in the diet; a diverse, whole-foods, plant-based diet will provide all of the calcium you need.

3. “Chicken, turkey, fish, and eggs are healthy sources of protein.”

Chicken, turkey, fish, and eggs contain significant amounts of cholesterol and saturated fat, in many cases as much as beef,16 so they are not “heart healthy” foods. Plant-based sources of protein contain zero cholesterol and far less saturated fat. Chicken and turkey usually contain antibiotics, pesticides, and fecal contaminants, and have been associated with salmonella, staph, and other infectious disease outbreaks. Chicken, fish, and eggs have been associated with an increased risk of diabetes.17-25 Almost all fish contain mercury, which can cause neurologic and cognitive problems; many also contain polychlorinated biphenyls (PCBs), a toxin associated with cancer.16 And a recent study showed that eggs cause intestinal bacteria to make a substance called TMAO, which can trigger heart attacks and other cardiovascular events.26

Whole plant foods supply plenty of protein, and they don’t come packaged with cholesterol or high levels of saturated fat. Instead, their protein is bundled with fiber and many necessary nutrients! Great plant-based sources of protein include lentils, chickpeas, black beans, kidney beans, soybeans, and quinoa. Green vegetables such as spinach, collards, broccoli, and peas are also quite high in protein per calorie. But remember, it’s not necessary to seek out plant foods high in protein, since a varied whole-food, plant-based diet will naturally provide enough protein, without special effort.27

4. “I can’t eat carbs.”

Many people are mistakenly led to believe they should avoid carbohydrates, particularly for weight management and diabetes control. Instead, they focus on proteins — especially animal proteins — and fats. Sadly, this approach actually increases the risk of chronic disease and death,28-32 and it deprives people of the numerous nutrients found in carbohydrate-containing foods.

It is true, however, that not all carbohydrates are created equal. Refined, highly processed carbohydrates can raise triglycerides, promote weight gain, and drive up blood sugar. On the other hand, starches that come from whole grains bring fiber, essential fatty acids, B vitamins, zinc, and protein into our diets and provide an excellent source of energy. Beans, legumes, starchy vegetables, and fruits are other healthy carbohydrate sources. Balancing these foods with nonstarchy vegetables is an optimal way to eat for weight loss, diabetes control, and reversal of heart disease.

5. “Healthy food is too expensive.”

You don’t need to shop at a gourmet health food store to find nutritious foods. Actually, some of the healthiest foods are the least expensive, and they are readily available at most grocery stores and many local farmers’ markets. Beans, lentils, brown rice, and frozen vegetables are usually inexpensive, especially when bought dried and in bulk. (Organic fruits and vegetables can cost more, but eating nonorganic plant-based foods is still more nutritious than eating meat, chicken, fish, eggs, and dairy, organic or otherwise.)

Even when processed foods and animal products are sold cheaply, they are expensive in terms of the cost to your health. What you may save now, you could end up spending later in pharmacy co-payments and medical bills!

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Michelle McMacken, M.D., is a board-certified internal medicine physician and an assistant professor of medicine at NYU School of Medicine.  She practices primary care at Bellevue Hospital Center in New York City, where she also directs a medical weight-loss program.  An enthusiastic supporter of plant-based nutrition, she is committed to educating patients, medical students, and doctors about the power of healthy eating and lifestyle modification. Be sure to connect and follow Dr. McMacken on Twitter.

This article was previously published on Forks Over Knives.

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References:

1 Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Washington, DC: National Academies Press; 2002.

2 Rizzo NS, Jaceldo-Siegl K, Sabate J et al. Nutrient profiles of vegetarian and nonvegetarian dietary patterns. J Acad Nutr Diet 2013; 113(12):1610-9.

3Campbell TC, Campbell TM. The China Study: Startling Implications for Diet, Weight Loss, and Long-Term Health. Dallas: BenBella Books; 2006.

4 Barnard NB, Weissinger R, Jaster BJ, et al. Nutrition Guide for Clinicians, First Edition. Washington, DC: Physicians Committee for Responsible Medicine; 2007.

5 U.S. Department of Health and Human Services. Bone Health and Osteoporosis: A Report of the Surgeon General. Rockville, MD: U.S. Department of Health and Human Services, Office of the Surgeon General; 2004.

6 Feskanich D, Willett WC, Colditz GA. Calcium, vitamin D, milk consumption, and hip fractures: a prospective study among postmenopausal women. Am J Clin Nutr 2003; 77:504-11.

7 Michaëlsson K, Wolk A, Langenskiöld S, et al. Milk intake and risk of mortality and fractures in women and men: cohort studies. British Medical Journal2014;349:g6015.

8 Qin LQ, Xu JY, Wang PY, et al. Milk consumption is a risk factor for prostate cancer: Meta-analysis of case-control studies. Nutr Cancer 2004; 48(1):22-7.

9 Qin LQ, Xu JY, Wang, PY, et al. Milk consumption is a risk factor for prostate cancer in Western countries: Evidence from cohort studies. Asia Pac J Clin Nutr 2007; 16(3):467-76.

10 Chan JM, Stampfer MJ, Ma J, et al. Dairy products, calcium, and prostate cancer risk in the Physicians’ Health Study. Presentation, American Association for Cancer Research, San Francisco, April 2000.

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14 http://nutritionfacts.org/video/phytates-for-the-prevention-of-osteoporosis/

15 López-González AA, Grases F, Monroy N, et al. Protective effect of myo-inositol hexaphosphate (phytate) on bone mass loss in postmenopausal women. Eur J Nutr 2013; 52(2):717-26.

16 Simon, D. Meatonomics. San Francisco, Conari Press, 2013.

17Li Y, Zhou C, Zhou X, et al. Egg consumption and risk of cardiovascular diseases and diabetes: a meta-analysis. Atherosclerosis 2013; 229(2):524-30.

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20 Tonstad S, Butler T, Yan R, et al. Type of vegetarian diet, body weight, and prevalence of type 2 diabetes. Diabetes Care 2009; 32(5):791–6.

21 Chiu TH, Huang H, Chiu Y. Taiwanese vegetarians and omnivores: dietary composition, prevalence of diabetes and impaired fasting glucose. PLoS One 2014; 9(2):e88547.

22 van Nielen M, Feskens EJ, Mensink M. Dietary protein intake and incidence of type 2 diabetes in Europe: the EPIC-InterAct Case-Cohort Study. Diabetes Care 2014; 37(7):1854-62.

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24 Kaushik M, Mozaffarian D, Spiegelman D, et al. Long-chain omega-3 fatty acids, fish intake, and the risk of type 2 diabetes mellitus. Am J Clin Nutr 2009; 90:613–20.

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27 Young VR, Pellett PL. Plant proteins in relation to human protein and amino acid nutrition. Am J Clin Nutr 1994; 59 (suppl):1203S-1212S.

28 Larsson SC, Orsini N. Red meat and processed meat consumption and all-cause mortality: a meta-analysis. Am J Epidemiol 2014; 179(3):282-9.

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32 de Koning L, Fung TT, Liao X, et al. Low-carbohydrate diet scores and risk of type 2 diabetes in men. Am J Clin Nutr 2011; 93(4):844-50.

As always the information presented in this blog is for educational purposes only. It should not be considered as specific medical, nutritional, lifestyle, or other health-related advice.