The 10 Worst Health Risks of a Vegetarian Diet.

4. Loss of Bone Mineral Density

A 1998 study examined the bone mineral density of 45 people. Twenty-three were vegetarians and 22 were not. The study found that the vegetarian group had a mean density of 1.148, as opposed to 1.216 for the meat-eaters. A follow-up study found bone density increasing over the course of a year in the meat-eating group, while the mean density of the vegetarian group remained the same.

3. Pregnancy Risks

Sometimes a vegetarian will take up moderate amounts of fish or other meat during pregnancy. Women who remain vegetarians while pregnant run the risk of irregular menstrual cycles and low caloric intake which can have a deleterious effect on the weight and health of the baby. Mothers can avoid this by eating a well-rounded diet of fruits and vegetables, starches, dairy foods, and protein.