Research Shows Vegan Diet Leads to Nutritional Deficiencies, Health Problems; Plant

Although the vegan diet is often promoted as being good for heart health, eliminating consumption of animal products may cause nutritional deficiencies and could lead to negative consequences, according to a comprehensive review published in the medical journal Progress in Cardiovascular Diseases.

Noting an absence of randomized controlled trial data showing long-term safety or effectiveness of its restrictive eating patterns, researchers conducted a scientific review of published literature on the vegan diet, as well as the evolutionary history of the human diet.

"As fundamental as diet is to health, you need to keep in mind the diet for which we’ve been adapted genetically, "said James O’Keefe, MD, the study's lead author and director of preventive cardiology at Saint Luke's Mid America Heart Institute. "Animal-based foods have been an important part of the human diet for at least three million years. Eliminating all animal foods would be like deciding you’re going to feed a tiger tofu and expect that it's going to be healthy. If you want an organism to thrive, you should feed it the diet for which it's been genetically adapted via evolution down through the ages."

Compared to the standard American diet of highly processed, low-fiber, high-calorie, sugary foods, vegan diets have some health advantages. However, researchers found that avoiding all animal foods may lead to nutritional deficiencies in vitamin B12, omega-3, calcium, zinc, iron, magnesium, and high-quality protein.

These deficiencies may be associated with increased risk for certain types of cancer, stroke, bone fractures, preterm birth, and failure to thrive. Avoiding consumption of animal-sourced food may also be related to higher rates of depression and anxiety. Hair loss, weak bones, muscle wasting, skin rashes, hypothyroidism, and anemia are other issues that have been observed in those strictly following a vegan diet.

On the other hand, consuming excess processed meats and/or burned, fatty meat can also be detrimental to a person's health. Researchers noted it is important to be selective about the animal-based foods consumed.

Instead of eliminating all animal-sourced foods, researchers concluded that a plant-forward omnivorous, whole-foods diet may be a more effective dietary approach to improving life expectancy.

A plant-forward omnivorous whole foods diet consists of natural, unprocessed foods rich in vegetables, nuts, seeds, avocados, olive oil, berries, and other fruits, along with whole grains and legumes. Animal foods such as wild-caught seafood, pasture-raised meats, eggs, and unsweetened dairy are also essential to the diet.

"If you’re eating a strict vegan diet, it is very difficult to supplement enough of all of the nutrients and high-quality protein that you need to be strong and healthy," O’Keefe said. "If you’re doing it for your health, there is no substitute for eating the natural whole foods—you’re better off eating wholesome animal foods that are not overcooked and/or highly processed; understanding this is vitally important for your health."

Researchers noted that future prospective studies are needed to evaluate the cardiovascular effects of a plant-forward omnivorous whole-foods diet to support the observational findings.

Read the full article "Debunking the Vegan Myth: The Case for a Plant-Forward Omnivorous Whole-Foods Diet" in Progress in Cardiovascular Diseases.

About Saint Luke's Mid America Heart Institute Saint Luke's Mid America Heart Institute, part of Saint Luke's Health System and a teaching affiliate of the University of Missouri-Kansas City, is one of the preeminent cardiovascular programs in the country. Its legacy of innovation began more than 35 years ago when it opened as the nation's first heart hospital. Since then, the Heart Institute has earned a world-wide reputation for excellence in the treatment of heart disease, including interventional cardiology, cardiovascular surgery, imaging, heart failure, transplant, heart disease prevention, women's heart disease, electrophysiology, outcomes research, and health economics. With more than 65 full-time board-certified cardiovascular specialists on staff, the Heart Institute offers one of the largest heart failure/heart transplant programs in the country, has the most experience with transcatheter aortic valve replacement in the Midwest, and is a global teaching site for the newest approaches to opening challenging blocked arteries using minimally invasive techniques.

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