Is it healthier to be vegan than to eat meat?: answers from a study with identical twins


As many prepare to make drastic changes to their diet in the new year, a recent study sheds clues on which is healthier: a vegan or omnivorous diet?

Vegans avoid all foods from animals, such as meat, fish, dairy, eggs and honey. On the other hand, an omnivorous diet allows you to consume foods of both plant and animal origin.

The new study reveals that following a vegan diet has multiple benefits, but some nutritionists say that That does not mean that you should abandon foods of animal origin be the appropriate response for all people.

What the researchers found

The new research findings, published Nov. 30 in the Journal of the American Medical Association (JAMA), followed 22 pairs of identical twins for eight weeks, while one twin in each pair followed a vegan diet and the another an omnivorous diet.

The diets of both groups were designed to be healthy, with plenty of vegetables, fruits and whole grains, and limited in added sugars, refined grains and overly processed foods.

“Each set of twins was randomly assigned to one of the two diets, so neither could choose their own diet,” explained Dr. Christopher Gardner, a professor of medicine at Stanford University School of Medicine and senior author of the study. study.

Using identical twins to measure study results was critical because external factors often influence the conclusions of nutrition-related studies, he said.

Additionally, because each set of twins had the same genes, the same education, and similar attitudes and behaviors toward food and exercise, Gardner said the research provided more reliable data than other randomized clinical trials.

(They plan to increase the benefits of the supplemental feeding program starting in October)

The results showed that The vegan diet had better results in cardiometabolic health compared to the omnivorous diet, such as: a 20% decrease in insulin levels, a 12% decrease in “bad” cholesterol and a 3% decrease in body weight.

The benefits of a vegan diet

All participants began the study at a healthy weight and had insulin and cholesterol levels within a normal range, “so there wasn’t much room for improvement, and yet they improved, and in just eight weeks,” said Gardner, who He added that the research also showed other health benefits in the vegan group that are still being analyzed and will be published in a later study.

Those in the omnivorous group did not experience any changes that were detrimental to their health.

“Many of the benefits (of a vegan diet) are described in this study and supported by other research,” said Messer, a registered dietitian and president-elect of the New Hampshire Academy of Nutrition and Dietetics. She did not participate in the study.

Messer added that heart health benefits like these are expected with a “well-balanced vegan diet that is abundant in fruits, vegetables, whole grains, and plant-based proteins.”

“The bottom line is not that everyone should become vegan.”

The study results do not necessarily mean that veganism is better than an omnivorous diet, the experts explained.

“The bottom line is not that everyone should go vegan,” Gardner explained. Rather, it is that “it is quite likely that partial benefits will be obtained simply by replacing some of the meat in the diet with more plant foods.”

Messer agreed, adding that he always advises his clients to incorporate more plant-based foods into their diet to improve cardiovascular health.

“Often I recommend ‘meatless Mondays’ or something similar, as an easy way to add more plant-based protein. to the diet without fully committing to a vegan plan that may not be attractive to everyone,” he said.

Another way to temporarily try a vegan diet is to participate in the so-called “Veganuary”: avoiding animal products during the month of January. There are many easy to follow recipes.

Is it bad to eliminate an entire food group?

Messer said completely eliminating any food group can be detrimental to your health if not done carefully.

“Eliminating an entire food group, such as with a vegan diet, can leave you without key nutrients,” he explained. “A vegan dietary pattern can pose limitations in nutrients such as vitamin B12, iron, omega-3s and calcium, as numerous studies show.”

A deficiency of vitamin B12, which is only found in animal products, can lead to neurological problems, fatigue and potentially long-term nerve damage. Iron deficiency can cause anemia and impaired cognitive function.

Likewise, a lack of calcium can weaken bones and increase the risk of fractures. Omega-3 fatty acids play an important role in heart health, brain function, and regulating inflammation.

To avoid these deficiencies, Messer said vegans often need “supplements or meticulous meal planning.”

“Enjoy” food choices

For some people, a vegan diet may also be less satisfying: Twins in the vegan group in the study reported less overall satisfaction than those in the omnivore group.

But regardless of your dietary restrictions, “there are many ways to build a healthy dietary pattern that is consistent with personal and cultural preferences,” said Alice Lichtenstein, director of cardiovascular nutrition at the Jean Mayer USDA Human Nutrition Research Center at Tufts University. .

“The fundamental thing is that the healthy dietary pattern is enjoyed, is consistent with each person’s lifestyle and is maintained in the long term,” he says.

And being vegan isn’t inherently healthier either.

“One way to follow a vegan diet is to eliminate beef, chicken, pork, fish, dairy and eggs, replacing them with sodas, vegan cookies and vegan snacks. That would have its dangers,” Gardner said.

Whether or not you eat animal products, “a reasonable variety of vegetables, legumes, whole grains, nuts, seeds and fruits should provide all the nutrients necessary to lead a full and active life,” he added.