Scientific Update
By Reed Mangels, PhD, RD, FADA
VRG’s Simply Vegan Used in Study that Examined Use of Vegan Diets in Coronary Artery Disease
Inflammation is part of our immune response. If we’re exposed to harmful bacteria, for instance, short-term inflammation can help to protect us. When inflammation is present most of the time, however, it can be harmful. Many chronic diseases, including heart disease and arthritis, have been linked with chronic inflammation. A recent study examined whether or not a vegan diet could help reduce chronic inflammation in people with coronary artery disease. Coronary artery disease is the most common type of heart disease and is the leading cause of death in men and women in the U.S. In coronary artery disease, the blood vessels that supply blood to the heart become narrowed due to the buildup of plaque on the inside of the arteries. This keeps the heart from getting the blood and oxygen that it needs. A persistent low level of inflammation is believed to play a major role in coronary artery disease.
One way to assess inflammation is to do a blood test measuring high-sensitivity C-reactive protein. Higher concentrations of high-sensitivity C-reactive protein indicate an increased risk of heart disease. Study participants all had partial blockage of one or more major blood vessels; a majority had elevated cholesterol and blood pressure. Almost all were being treated with medications. They were divided into two groups. Groups were instructed to follow either an American Heart Association-recommended (AHA) diet (less than 5-ounces of animal protein per day, fish more than twice a week, only lowfat or non-fat dairy products) or a vegan diet for eight weeks. One of the tools that was provided to subjects on the vegan diet was Simply Vegan, by VRG’s Debra Wasserman. The AHA group received a copy of an AHA cookbook and other materials. At the end of the study, the vegan group had a significantly lower concentration of high-sensitivity C-reactive protein, an important marker of inflammation.
This means that the group on the vegan diet had a lower risk of exposure to harmful inflammation. The vegans had a higher intake of fiber and whole grains and were more likely to comply with the diet compared to those following the AHA diet. The researchers conclude that a vegan diet can be a part of treatment of coronary artery disease to reduce harmful inflammation.
Shah B, Newman JD, Woolf K, et al. 2018. Anti-inflammatory effects of a vegan diet versus the American Heart Association-recommended diet in Coronary Artery Disease Trial. J Am Heart Assoc. 4;7(23):e011367.
Vegetarians and Gallbladder Disease
A couple of years ago (Vegetarian Journal Issue 4, 2017), we reported on a study from the UK that found vegetarians were at a moderately higher risk (~22%) of developing symptomatic gallbladder disease than were non-vegetarians. A recent study from Taiwan finds that vegetarian women, but not vegetarian men, are at a lower risk of symptomatic gallbladder disease compared to non-vegetarians. Close to 5,000 people were studied. Based on interviews and questionnaires, almost 30% were vegetarians (no meat, fish, or poultry). Both vegetarians and non-vegetarians ate only a small amount of eggs and dairy products. The study subjects were tracked for an average of six years to see who would develop symptomatic gallbladder disease. Over the course of the study, 2.3% of non-vegetarians and 1.5% of vegetarians were diagnosed with symptomatic gallbladder disease. Vegetarian women had almost a 50% lower risk of symptomatic gallbladder disease compared to non-vegetarian women. Because the nonvegetarian women only ate small amounts of meat, the researchers hypothesize that the effects of a vegetarian diet in reducing risk of symptomatic gallbladder disease in women may be even greater in populations where more meat is eaten.
Chang CM, Chiu THT, Chang CC, Lin MN, Lin CL. 2019. Plant-based diet, cholesterol, and risk of gallstone disease: a prospective study. Nutrients. 11(2). pii: E335.
