I have no argument with people who adopt a vegetarian or vegan diet for health, religious, environmental or ethical reasons. But I object vehemently to proselytizers who distort science or the support for dietary advice offered to the more than 90 percent of us who choose to consume animal foods, including poultry and red meat, in reasonable amounts.
Such is the case with a recently released Netflix documentary called “What the Health” that several well-meaning, health-conscious friends urged me to watch. And I did try, until I became so infuriated by misstatements — like eating an egg a day is as bad as smoking five cigarettes, or a daily serving of processed meat raises the risk of diabetes 51 percent — that I had to quit for the sake of my health. While the film may have laudable goals, getting the science wrong confuses the issues and infuriates those who might otherwise be supportive.
Please understand: I do not endorse inhumane treatment of farm animals or wanton pollution of the environment with animal wastes and misused antibiotics and pesticides. Agricultural research has long shown better ways to assure an adequate food supply if only regulators would force commercial operations to adopt them.
Nor do I endorse careless adoption of vegetarian or vegan diets for their name’s sake. A vegan who consumes no animal products can be just as unhealthy living on inappropriately selected plant foods as an omnivore who dines heavily on burgers and chicken nuggets. A vegan diet laden with refined grains like white rice and bread; juices and sweetened drinks; cookies, chips and crackers; and dairy-free ice cream is hardly a healthful way to eat.
Current dietary guidelines from responsible, well-informed sources already recommend that we should all adopt a plant-based diet rich in foods that originate in the ground, “fleshed out” with low-fat protein sources from animals or combinations of beans and grains. However, here too careless food and beverage selections can result in an unhealthful plant-based diet.
A very large study recently published in the Journal of the American College of Cardiology is a case in point. The study, by a team from Harvard’s T.H. Chan School of Public Health, examined the relationship between plant-based diets of varying quality and the risk of developing coronary heart disease among more than 200,000 health professionals. The participants, who started the study free of chronic disease, were followed for more than two decades, submitting their dietary patterns to the researchers every two years.
Based on their responses on food-frequency questionnaires, the participants’ diets were characterized by the team as an overall
plant-based diet that emphasized plant foods over animal foods; a healthful plant-based diet emphasizing healthful plant foods; or an unhealthful plant-based diet. Any of the diets could have included various amounts of animal products.
Healthful plant foods like whole grains, fruits, vegetables, nuts and legumes, as well as vegetable oils, coffee and tea, received a positive score; less-healthful plant foods like juices, sweetened beverages, refined grains, fries and sweets, along with animal foods, received a negative rating.
The more closely the participants adhered to a healthful plant-based diet, the less likely they were to develop heart disease in the course of the study. Those with the least healthful plant-based diet were, on average, 32 percent more likely to be given diagnoses of heart disease. In a prior study, the researchers found a similar reduction in the risk of Type 2 diabetes.
The team, led by Ambika Satija of Harvard’s Department of Nutrition, concluded that “not all plant foods are necessarily beneficial for health.”
The Harvard finding was nearly identical to one from an 11-year European study that found a 32 percent lower risk of coronary heart disease among vegetarians than among nonvegetarians, although no health-based rating was given to the quality of the participants’ vegetarian diets.
The more detailed Harvard study, which examined adherence levels to a plant-based diet, found that “even a slightly lower intake of animal foods combined with a higher intake of healthy plant foods” was associated with a lower risk of heart disease.
In other words, you don’t have to become a strict vegetarian to protect your heart. Simply reducing your dependence on animal foods, and especially avoiding those high in fat, is helpful. In fact, “a diet that emphasized both healthy plant and healthy animal foods” was associated with a coronary risk only slightly higher than a diet based almost entirely on healthy plant foods, the researchers found.
On the other hand, overdoing “less healthy plant foods” and less healthy animal foods like red and processed meats, the study showed, significantly increased the risk of developing heart disease.
The Harvard findings support the most recently released Dietary Guidelines for Americans that urge people to consume large amounts of “high-quality plant foods,” the researchers noted. They added that the recommended diet “would also be environmentally sustainable” because plant-based food systems require fewer resources than animal-based ones.
Thus, the more plants and the fewer animal products you eat, the lower your carbon footprint and the less you contribute to animal suffering. But to be truly beneficial, the plants you choose must be nutrient rich.
Though most Americans rely heavily on animal foods for protein, getting quality protein is not hard with a vegetarian diet that includes dairy and eggs. Pescatarians, who add fish to their diet, get a nutritious bonus of omega-3 fatty acids along with high-quality protein from fish and shellfish.
Those choosing a strict vegan diet — one devoid of all foods from animals — face a greater challenge because the protein in plants is not complete and must be balanced by consuming complementary sources, like beans and grains. A sandwich of almond butter or peanut butter on whole grain bread is totally vegan and an excellent example of balanced protein in a high-quality plant-based diet. Vegans also must supplement their diet with the vitamin B-12.
Short of becoming a vegan, you can improve your diet, protect your health and add variety to your meals with a few simple dietary adjustments. As Dr. Hena Patel and Dr. Kim Allan Williams Sr., cardiologists at Rush University Medical Center in Chicago, suggested in a commentary on the Harvard study, you might choose one day a week to be meatless and gradually add more meatless days while adding one or more new plant-based recipes each week.
I bet you’ll be pleasantly surprised at how much more delicious and varied your meals will be.