Low bone mass in subjects on a long-term raw vegetarian diet

Little is known regarding the health effects of a raw food (RF) vegetarian diet.

We performed a cross-sectional study on 18 volunteers (mean +/- SD age, 54.2 +/- 11.5 years; male/female ratio, 11:7) on a RF vegetarian diet for a mean of 3.6 years and a comparison age- and sex-matched group eating typical American diets. We measured body composition, bone mineral content and density, bone turnover markers (C-telopeptide of type I collagen and bone-specific alkaline phosphatase), C-reactive protein, 25-hydroxyvitamin D, insulin-like growth factor 1, and leptin in serum.

The RF vegetarians had a mean +/- SD body mass index (calculated as weight in kilograms divided by the square of height in meters) of 20.5 +/- 2.3, compared with 25.4 +/- 3.3 in the control subjects. The mean bone mineral content and density of the lumbar spine (P= .003 and P<.001, respectively) and hip (P = .01 and P<.001, respectively) were lower in the RF group than in the control group. Serum C-telopeptide of type I collagen and bone-specific alkaline phosphatase levels were similar between the groups, while the mean 25-hydroxyvitamin D concentration was higher in the RF group than in the control group (P<.001). The mean serum C-reactive protein (P = .03), insulin-like growth factor 1 (P = .002), and leptin (P = .005) were lower in the RF group.

A RF vegetarian diet is associated with low bone mass at clinically important skeletal regions but is without evidence of increased bone turnover or impaired vitamin D status.