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!
***
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.
***
References:
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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.
