The prevalence of people who follow plant-based vegetarian and vegan diets is on the rise, for reasons including environmental sustainability, improved health, and concerns for animal welfare. The latest update to the Dietary Guidelines for Americans includes vegetarian and vegan options that meet all nutrient requirements; however, much of the research contributing to these recommendations was conducted in adults. A recent report describes the effect of plant-based diets on growth and cardiovascular disease risk factors in children.

Although cardiovascular disease is considered a disease of aging, risk factors in childhood, such as poor diet and sedentary lifestyle, may translate to earlier onset and increased severity of disease in adulthood. One review of observational studies reported that people who adhered to vegetarian and vegan diets had a reduced risk of ischemic heart disease and cancer than people who ate a mixed diet. However, vegetarian and vegan diets tend to provide less calcium and have been associated with an increased risk of fractures, a concern for growing children.

The researchers recruited families with children between the ages of five and ten years, who had a normal body mass index (between 18.5 and 29.9), and who followed a vegetarian or vegan diet. Then they recruited a group of age-matched children who consumed an omnivorous diet, with almost 200 participants total. The researchers collected data from the participants, including family health history and lifestyle, cardiometabolic markers, body composition, and arterial blood flow. The participants wore an activity monitor for two days and kept a food journal for four days to assess their habitual eating and activity habits.

Compared to children that consumed an omnivorous diet, children who ate a vegetarian or vegan diet had less fat mass but similar amounts of lean muscle mass. Vegetarian and vegan children also had lower bone mineral density, although this relationship was not significant in vegetarian children when taking height into account. Vegetarian children had lower total cholesterol, good HDL cholesterol, and serum vitamin B12 and vitamin D without sufficient supplementation. They also had higher glucose, bad VLDL cholesterol, and triglycerides, markers of poor cardiometabolic health. Vegan children were shorter and had lower total cholesterol, including good HDL and bad LDL cholesterol, and less inflammation, but were also more likely to have low iron and vitamin B12 levels without sufficient supplementation.

The authors concluded that vegan children had lower cardiovascular disease risk but had an increased risk of nutritional deficiencies, lower bone mineral density, and shorter height. Vegetarian children had less severe nutritional deficiencies but, unexpectedly, a less favorable cardiometabolic risk profile.

• Link to full report.