A vegan diet has been shown to significantly improve cardiovascular health in as little as eight weeks. The study, conducted by Stanford Medicine researchers, which involved 22 pairs of identical twins, aimed to minimise genetic and environmental factors that often complicate diet studies.
The research, soon to be published in JAMA Network Open, marks a pivotal moment in understanding the impact of veganism on cardiovascular health. "Not only did this study provide a groundbreaking way to assert that a vegan diet is healthier than the conventional omnivore diet, but the twins were also a riot to work with," remarked Christopher Gardner, the Rehnborg Farquhar Professor and a professor of medicine.
The trial, conducted from May to July 2022, included a total of 44 participants, with one twin from each pair assigned either a vegan or omnivore diet. Both diets were carefully designed to be healthy, consisting of vegetables, legumes, fruits, and whole grains, while excluding sugars and refined starches. The vegan diet completely eliminated meat and animal products, such as eggs and milk, while the omnivore diet included a variety of animal-sourced foods.
During the initial four weeks, participants received a meal delivery service that provided 21 meals per week, followed by four weeks where they prepared their own meals. Throughout the study, a registered dietitian provided guidance and support to the participants.
The results were remarkable. The participants following a vegan diet exhibited significant improvements in cardiovascular health markers over the first four weeks. They experienced lower levels of low-density lipoprotein cholesterol (LDL-C), insulin, and body weight compared to their omnivorous counterparts. LDL-C levels dropped from an average of 110.7 mg/dL to 95.5 mg/dL among vegans, while omnivores saw a decrease from 118.5 mg/dL to 116.1 mg/dL. The optimal healthy LDL-C level is below 100 mg/dL.
Moreover, the vegan participants showed a remarkable 20% reduction in fasting insulin levels, a risk factor for developing diabetes. They also shed an average of 4.2 more pounds than the omnivorous participants.
Lead researcher Christopher Gardner emphasized that incorporating more plant-based foods into one’s diet, rather than strictly adhering to a vegan lifestyle, can still yield significant health benefits. "A vegan diet can confer additional benefits such as increased gut bacteria and the reduction of telomere loss, which slows aging in the body," Gardner noted.
The findings of this study suggest that making dietary changes towards a more plant-based lifestyle can have a profound impact on cardiovascular health. While not everyone may choose to adopt a vegan diet, even small steps towards incorporating more plant-based foods can lead to improved well-being.
