We know from the work of Drs. Dean Ornish and Caldwell B. Esselstyn that switching to a plant-based diet can reverse heart disease, opening up arteries in some cases without drugs or surgery. We can’t wait until our first heart attack to start eating healthy, though, because our first symptom of heart disease may be our last. Fifty percent of men and 64% of women who die suddenly from coronary heart disease have no previous symptoms.
To predict the risk of dying from a heart attack, we can measure risk factors such as cholesterol levels and blood pressure. Wouldn’t it be nice to actually see what’s going on inside our arteries before it’s too late? Our imaging technologies are so good that we can, but the required dose of radiation delivered to one’s chest is so high that a young woman getting just a single scan may increase her lifetime risk of breast cancer and lung cancer by between around 1% and 4%.
Our carotid arteries, though, which connect our heart to our brain, come close enough to the surface in our necks that we can visualize the arterial wall using harmless sound waves (ultrasound). Carotid artery wall thickness is what was measured in the study I profiled in Eggs vs. Cigarettes in Atherosclerosis. How do the arteries of those eating plant-based diets compare to those eating the standard American diet? Researchers gathered up some vegans to find out.
In the video above, you can see the thickness of the inner wall of the carotid arteries where the atherosclerotic plaque (considered a predictor of all-cause and cardiovascular mortality) builds up in the standard American diet group. This same inner layer was significantly slimmer in vegans, but so were the vegans themselves. Those eating the standard American diet were, on average, overweight with a BMI over 26 while the vegans were a trim 21—36 pounds lighter on average.
So maybe the only reason those eating meat, eggs, and dairy had thickened arterial walls was because they were overweight—maybe the diet per se had nothing to do with it. To solve the riddle one would have to find a group of people still eating the standard American diet, but as slim as vegans. To find a group that trim, researchers had to use long-distance endurance athletes, who ate the standard American diet, but ran an average of 48 miles per week for 21 years. Both the vegans and the conventional diet group were sedentary—less than an hour of exercise a week.
As you can see in the video above, the average thickness of endurance runners’ carotid arteries is between that of sedentary vegans and omnivores. It appears that if we run an average of about a thousand miles every year we can rival some couch potato vegans. But that doesn’t mean we can’t do both. Read more about the study here.
Another comparison between athletes and plant-eaters can be found in Is It the Diet, the Exercise, or Both? It compares cancer-fighting abilities with a similar result.
Not all studies showed vegans have superior arterial form and function. Find out why in my video Vitamin B12 Necessary for Arterial Health.
Michael Greger, M.D.