Twins were given vegan meals, meals with meat. One group had much lower heart disease risk

The impact of food on long-term health is difficult to study. So many nutritional studies will conclude with “this was an observational or prospective study so it does not prove cause and effect.”

Often, the best that can be said is that there was an association. I know this can be frustrating, but it also happens to be the truth. So when we find a clinical trial that makes a point about food intake, we feel more confident saying that this can be cause an effect. And it might be a motivator to change eating patterns.

A small clinical trial published last month in JAMA Network compared the effects of a healthy vegan diet to a healthy omnivore diet during the eight-week study period. Twenty-two pairs of identical twins were divided into two groups. Using twins minimizes genetic influences.

Now, this seems like a small number but I remember when NASA wanted to study the impact of long space flight on body function. Luckily there were twin astronauts Mark and Scott Kelly. Scott Kelly’s trip lasted 340 days in space and when he returned home every body function and bio marker was compared with his twin brother Mark, who had remained on earth. So this study of 22 pairs of twins seems big in comparison

One twin from each pair received vegan meals for eight weeks and the other twin received a healthy mixed diet. Both meal plans were low in sugar and refined grains. Interestingly, all participants received meal service for the first four weeks. During the second half of the study, they had to prepare their own food. There was only one dropout, which is remarkable and shows one can learn to make vegan meals in a short time period

The twins on the vegan diet had significantly lower LDL cholesterol, lower fasting insulin levels and lost more weight. All these factors contribute to reduced risk of heart disease. Another piece of evidence supporting a plant-based food intake.

Sheah Rarback MS, RDN is a registered dietitian nutritionist in private practice in Miami. srarback@hotmail.com