‘Vegan vs Omnivore’ Diet Tested by Twins…Which Diet Is Healthier?

A recent study comparing a vegan diet with an omnivore diet found that the vegan diet significantly improved overall cardiovascular health.

On the 2nd, a team led by Professor Christopher Gardner of Stanford University in the United States published the results of a clinical trial on 22 identical twins in the Journal of the American Medical Association (JAMA) Network Open. The study involved having each twin follow either a fully vegetarian or an omnivorous diet, and the results showed that a fully vegetarian diet was more effective in improving cardiovascular health compared to an omnivorous diet

Numerous studies have previously revealed the positive impact of a vegetarian diet on health. While it is well known that consuming less meat is beneficial for cardiovascular health, proving this through dietary research has been challenging due to factors such as genetic differences, and lifestyle habits.

The research team explained that identical twins, who grew up in the same family and have similar lifestyles, allow for the control of genetic factors and the limitation of other variables in the study.

The study was conducted with 22 pairs of identical twins, a total of 44 participants, who were in a healthy state with no cardiovascular diseases from May to July 2022. Both diets were rich in vegetables, legumes, fruits, and whole grains, and free of sugar and refined starch.

The vegan diet did not include any animal-based foods such as meat, eggs, and milk, whereas the omnivorous diet included chicken, fish, eggs, cheese, and dairy products.

Reduction in fasting insulin levels… Vegan participants’ health significantly improved

For the first four weeks, the identical twins consumed meals provided 21 times, three times a day – breakfast, lunch, and dinner. For the remaining four weeks, the participants prepared their own meals following guidelines.

Body weights were measured and blood samples were collected at the start of the clinical trial, at the four-week mark, and at the eight-week mark. Forty-three participants completed the clinical trial.

The results of their health assessments were astonishing. The health of the participants who followed a vegan diet for the first four weeks significantly improved. Their levels of low-density lipoprotein cholesterol (LDL-C), which is harmful to cardiovascular health, insulin, and weight were all noticeably lower than those of the participants on the omnivorous diet.

The average LDL-C levels at the start of the clinical trial were 110.7 mg/dL for the vegan group and 118.5 mg/dL for the omnivorous group. However, at the end of the trial, the vegan group’s LDL-C levels improved significantly to 95.5 mg/dL, while the omnivorous group’s levels were 116.1 mg/dL.

The participants who followed the vegan diet also saw a reduction of about 20% in fasting insulin levels. Their weight also decreased by an average of 4.2 pounds more than the omnivorous group.

Professor Gardner stated, “Since most participants already had healthy LDL-C levels at the starting point, there was not much room for improvement.” However, he added, “Individuals with higher baseline levels may experience greater improvement effects.”

He continued, “This study, which used twins as subjects, provides a groundbreaking method to prove that a vegan diet is healthier than a traditional omnivorous diet. These results show that consuming more plant-based foods can help most people improve their health and longevity.”

In addition to these findings, plant-based diets have gained attention for their low-carbon footprint. The most significant advantage of a plant-based diet is that it does not require resources such as feed, water, energy, and land used in animal farming. According to the Seoul Environmental Union, producing 2.2 lb of beef requires approximately 35.3 lb of corn used for animal feed and an astonishing 4,086 gallons of water.

Major global institutions have highlighted the importance of vegetarianism as a means to address the climate crisis. According to the Ministry of Environment’s ‘Energy Consumption and Greenhouse Gas Emission Calculation Study of Food’, switching to a vegetarian meal once a day can reduce carbon emissions by about 7.16 pounds.

By. Eunha Kim