Eating a vegan diet is more beneficial for the environment than eating a Mediterranean diet, according to new research published in the International Journal of Environmental Research and Public Health.
For the study, the researchers aimed to compare two well-planned diets, the Mediterranean diet and the vegan diet, both of which are considered healthy and environmentally friendly, to determine how they differ in their environmental impacts.
They pointed out that the two diets are similar in that they both emphasize plant-based foods (vegetables, grains, legumes, fruit, nuts, and oil). The only qualitative difference between the two diets is that the animal protein foods of the Mediterranean diet are replaced with plant proteins in the vegan diet.
How do animal products impact the environment?
For the study, the researchers used the Life Cycle Assessment, a method to evaluate the environmental footprint of a product. The two diets that were assessed shared the same macronutrient rates and covered all the nutritional recommendations. Calculations were made on the basis of a theoretical one week diet based on 2,000 calories per day.
Specifically, the researchers assessed the impact of the two selected diets based on the “farm to table” method, which includes all the processes involved in the foods’ production such as agricultural production, transport, processing, packaging, and home preparation.
The researchers found that the vegan diet had 44 percent less total environmental impact when compared to the Mediterranean diet. The authors say that even modest consumption of animal products plays a critical role in damaging human and environmental health.
“This result clearly supports the concept that meat and dairy consumption plays a critical role, above all, in terms of damage to human health and ecosystems,” the researchers said in the study.
The study showed that even 10 percent of calories derived from animal products were responsible for about half of the global impact of the Mediterranean diet, with meat showing the largest contribution (around 30 percent), despite the small amount included in this particular diet.
“Our study supports the thesis that even a minimal-to-moderate content of animal foods has a consistent impact on the environmental footprint of a diet, and their reduction can elicit significant ecological benefits,” the researchers said.
Their calculations also showed that legumes were 84 percent lower than mixed meat in terms of impact, and soy milk’s total impact was 79 percent lower than cow’s milk.
“Diet has an impact on both health and the ecosystem. In our work, we have compared two sustainable diets with very similar nutrient compositions but with substantial differences in their total environmental impacts. The replacement of a small calorie quota (10.6 percent) represented by animal foods with plant foods showed significant improvement in the total environmental impact, especially for ecosystems and human health,” the study concluded.
“This suggests that the more plant-based the diet is, the less it will impact the environment,” the researchers said. “This information is noteworthy in light of how many countries show a diet rich in animal foods and how much this represents a global risk to sustainability.”
Vegan diet beats out Mediterranean for weight loss
Previous research comparing the two diets also shows that a vegan diet has better outcomes than a Mediterranean diet for weight loss, insulin sensitivity, and cholesterol levels. A study published in 2021 in the Journal of the American College of Nutrition found that a low-fat, plant-based diet is superior in achieving weight loss when compared to a standard Mediterranean diet.
The study found that participants lost an average of approximately 13 pounds on the vegan diet, compared with no mean change on the Mediterranean diet.
“While many people think of the Mediterranean diet as one of the best ways to lose weight, the diet actually crashed and burned when we put it to the test,” study author Neal Barnard, MD, president of Physicians Committee for Responsible Medicine, said in a statement at the time.
“In a randomized, controlled trial, the Mediterranean diet caused no weight loss at all,” he said. “The problem seems to be the inclusion of fatty fish, dairy products, and oils. In contrast, a low-fat vegan diet caused significant and consistent weight loss.”