By John Salak –
Vegan diets have plenty of advocates and lots of detractors as well—with both sides able to line up loads of research to back up their positions. Eating less meat, for example, is known to improve cardiovascular health, which on the surface would be a win for vegans. Unfortunately, these diet studies were often hampered by factors such as genetic differences, upbringing and lifestyle choices, limiting their ability to absolutely link to the cardiovascular benefits of a vegan diet.
Stanford Medicine researchers claim to have eliminated these factors by studying identical twins and ultimately confirming that a vegan diet can improve cardiovascular health in as little as eight weeks. By studying these pairs, researchers were able to control for genetics and limit the other factors because the twins grew up in the same households and reported similar lifestyles.
“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,” said Christopher Gardner, Ph.D., the Rehnborg Farquhar Professor and a professor of medicine. “They dressed the same, they talked the same and they had a banter between them that you could have only if you spent an inordinate amount of time together.”
Stanford’s work is welcomed news for the millions of people who battle heart disease even if they don’t embrace a wholly vegan diet. Cardiovascular disease, after all, is the leading cause of death in the U.S., taking a life every 33 seconds, according to the Centers for Disease Control & Prevention.
This recent research focused on 22 pairs of identical twins, none of whom had any cardiovascular diseases. Leveraging an existing research database, Stanford was able to find pairs in which one person was a vegan and the other an omnivore.
Both diets were healthy, replete with vegetables, legumes, fruits and whole grains and void of sugars and refined starches. The vegan diet was entirely plant-based, included no meat or animal products such as eggs or milk. The omnivore diet included chicken, fish, eggs, cheese, dairy and other animal-sourced foods.
Over the eight-week study, a service delivered 21 meals per week for the first four weeks, which included seven breakfasts, lunches and dinners. Participants prepared their meals for the final four weeks. They were also interviewed about their dietary intake and required to keep a log of the food they ate.
All but one of the participants completed the study, which Gardner maintained demonstrates how feasible it is to learn how to prepare a healthy diet in four weeks.
“Our study used a generalizable diet that is accessible to anyone, because 21 out of the 22 vegans followed through with the diet,” said Gardner, who is a professor in the Stanford Prevention Research Center. “This suggests that anyone who chooses a vegan diet can improve their long-term health in two months, with the most change seen in the first month.”
The most improvement came in the first four weeks as participants with a vegan diet registered significantly lower low-density lipoprotein cholesterol (LDL-C) levels, insulin and body weight than the omnivores. All these shifts are associated with improved cardiovascular health.
The vegan participants showed about a 20 percent drop in fasting insulin, which helps reduce the risk of developing diabetes. They also lost more than four pounds on average compared to omnivores. Ultimately, the vegan diet delivered three important improvements tied to better heart health. It helps these participants cut back on saturated fats, increase dietary fiber and lose weight.
“Based on these results and thinking about longevity, most of us would benefit from going to a more plant-based diet,” Gardner said.
The Stanford researchers acknowledged that while their results showed how a vegan diet delivered benefits, most people will probably not embrace it because of its relatively restrictive nature.
Some might even advise against a full-blown vegan in any event, citing concerns over its relative lack of nutrients, its drawbacks for individuals with existing conditions like osteoporosis, and the diet’s relative lack of proteins. Gardner, however, suggested that a healthy compromise might be an option in which individuals simply consume more plant-based foods.
“What’s more important than going strictly vegan is including more plant-based foods into your diet,” he said. “Luckily, having fun with vegan multicultural foods like Indian masala, Asian stir-fry and African lentil-based dishes can be a great first step.”