The fact that heart disease is the number one cause of death in the U.S. is, well, disheartening. But the good news is that it’s largely avoidable. The National Heart, Lung and Blood Institute estimates that as much as 80% of heart disease is preventable through diet and exercise — that’s huge.
If prioritizing heart health is one of your health goals, it’s natural to wonder how your diet can have an impact. According to a new Stanford Medicine study, following a vegan diet improves cardiovascular health more than an omnivorous diet, even if the omnivorous diet is a well-balanced one that consists of nutrient-rich foods.
If you’ve looked into eating for heart health even casually, this may come as a surprise. After all, the Mediterranean diet, which is omnivorous, is the way of eating that cardiologists most often recommend, and it’s been heralded as the healthiest diet by U.S. News for the seventh consecutive year.
Is eating a vegan diet better for heart health than the Mediterranean diet? Keep reading to find out what cardiologists believe and for their advice on how to choose between them.
How a vegan diet impacts heart health, according to the latest scientific data.
The Stanford Medicine study is the latest scientific study about diet and heart health that is making headlines. The study took into account 22 sets of identical twins. Each set of twins grew up in the same household and had similar lifestyles. Researchers conducted the experiment for eight weeks, tasking one twin from each set to follow a vegan diet while the other one followed an omnivorous diet that included chicken, eggs, dairy and other animal-sourced foods. Both diets were healthy and included lots of veggies, fruits, whole grains and legumes while minimizing ultra-processed foods high in sugar or refined starches.
Even in as short a time frame as two months, researchers saw that the vegan eaters’ heart health improved due to lower levels of low-density lipoprotein cholesterol (the “bad” cholesterol), lower insulin levels and more weight loss. The vegan eaters experienced an average insulin drop of 20%, which is noteworthy because high insulin levels are a risk factor for diabetes, which in turn increases the risk of cardiovascular disease.
None of the cardiologists interviewed for this article said they were surprised with the study’s results.
“The new study further corroborated everything we know about the vegan diet and heart health. We already know vegans usually have a better cardiovascular health profile compared to someone [who isn’t vegan],” said Dr. Adedayo Adeboye, a cardiologist in Memphis, Tennessee.
Dr. Ailin Barseghian El-Farra, a cardiologist with UCI Health, said the reason a vegan diet is good for heart health is because it’s high in fiber and low in saturated fat, two cornerstones of eating that keep LDL cholesterol from reaching unhealthy levels.
Of course, this only happens when someone follows a nutrient-rich vegan diet. Dr. Ajay J. Kirtane, the director of the Columbia Interventional Cardiovascular Care program and a professor of medicine at the New York-Presbyterian/Columbia University Irving Medical Center, pointed out that you can be vegan and eat a nutrient-poor diet of primarily carbs and sugar.
“The key is to make sure that protein intake is maintained and also that carbs and sugars aren’t overrepresented instead of healthier nutritional alternatives,” he said.
Even with all its benefits, Adeboye said there are drawbacks to the vegan diet that can impact heart health. “Deficiencies in vitamin B12, iron and calcium can be common in vegans,” he said. Vitamin B12 is important for heart health because it breaks down the protein homocysteine, which can increase the risk of heart disease and stroke when levels are high. Iron is needed to make hemoglobin, which delivers oxygen to the body. Calcium is important because it helps cells in the heart communicate. Because of this, Adeboye said it’s important for vegan eaters to be especially conscious of getting enough of these nutrients and to take a supplement if needed.
All three doctors said the reason a vegan diet is good for heart health is because it helps keep LDL cholesterol levels down and lowers the risk of gaining an unhealthy amount of weight — two major risk factors for heart disease that a wealth of scientific studies have shown to be true.
Is a vegan diet better for heart health than the Mediterranean diet?
The Mediterranean diet has long been heralded as the best way to eat for heart health. It prioritizes vegetables, fruit, whole grains, legumes, olive oil, moderate amounts of dairy, poultry, eggs and fish and low amounts of red meat.
“The Mediterranean diet has demonstrated not only reduction in cardiovascular risk factors such as lipids but also a reduction in death,” Barseghian said.
All three cardiologists said the vegan diet and the Mediterranean diet have a lot in common. Both prioritize vegetables, fruit, whole grains and legumes. But a big difference is that people following the Mediterranean diet often eat fish, which is high in omega-3 fatty acids. While the American Heart Association recommends eating fish twice a week to get enough omega-3s, Adeboye said there are vegan sources of the nutrient, including walnuts, flaxseeds, chia seeds, edamame and seaweed, that can accomplish the same thing. What’s more, one scientific study found that most vegans get enough omega-3s.
There aren’t many scientific studies that pit the Mediterranean diet and vegan diet against each other, but one small, monthlong study of 24 healthy adults between the ages of 18 and 35 found the Mediterranean diet to be slightly better for heart health because vegan eaters had lower levels of vitamin B12 and nutrients were absorbed better for the Mediterranean diet followers. Still, the vegans had lower LDL cholesterol and experienced more weight loss than the Mediterranean dieters, showing that both ways of eating have their benefits. Another study also showed that both ways of eating supported heart health.
How to know which heart-healthy diet to follow
Since there is enough science to support several different ways of eating to improve heart health, how can you know which diet to follow? All three cardiologists gave the same advice — pick a heart-healthy eating plan that you’re most likely to stick with long term.
“The main components of vegan eating and the Mediterranean diet are the same: a diet rich in fruits, vegetables, whole grains and legumes, and low — or no, in the case of vegan — intake of animal fat,” Barseghian said.
Adeboye emphasized that the eating style you pick doesn’t have to be followed perfectly either; it doesn’t have to be all or nothing. Especially if you are used to eating a lot of meat, he said that eating just one or two plant-based meals more a week than you’re used to is more beneficial than not doing it at all.
“Simply increasing the amount of plant foods you’re eating will reduce the risk of metabolic syndrome, diabetes, obesity and high blood pressure — all of which can negatively impact the heart,” he said.
What all the cardiologists said they want people to know is that eating mostly plant-based foods, including plant proteins, is good for your heart. But how you choose to get there is up to you. As long as this is the basis of the way you eat, your cardiovascular health will benefit.