A vegetarian diet can be a healthy lifestyle choice for young people, but in some cases it may be a cover for an eating disorder, a new study suggests.

Researchers found that among the more than 2,500 15- to 23-year-olds they surveyed, vegetarians ate more fruits and vegetables and less fat, and were less likely to be overweight than meat-eaters.

On the other hand, current vegetarians were more likely to report problems with binge-eating compared with non-vegetarians. Furthermore, former vegetarians were more likely to admit to taking extreme measures to control their weight — such as using diet pills or purging by vomiting or abusing laxatives.

The findings suggest that while vegetarian diets can be healthy, for some teenagers they may mask a drive to be thin, according to lead researcher Dr. Ramona Robinson-O'Brien of the College of Saint Benedict-Saint John's University in St. Joseph, Minnesota.

"Parents should talk to their child about the motivations for embarking on a vegetarian diet," Robinson-O'Brien told Reuters Health.

If the primary reason is weight loss, she noted, parents may need to dig deeper.

"If parents recognize that their child is particularly sensitive about appearance and pressure to conform to a cultural ideal, it is possible that he or she may also be experiencing body dissatisfaction," Robinson-O'Brien said.

She added that teenagers who have shown interest in various weight- loss methods might turn to vegetarianism as a "socially acceptable" way to avoid certain foods, or possibly to conceal unhealthy eating habits.

The study, which appears in the current issue of the Journal of the American Dietetic Association, is based on survey data from 2,516 teenagers and young adults. Roughly 85 percent had never been vegetarian, while 4 percent were currently vegetarian and 11 percent had been in the past.

On average, the researchers found, current vegetarians consumed five servings of fruits and vegetables each day and got less than 30 percent of their calories from fat. In contrast, lifelong meat-eaters averaged fewer than four servings of fruits and vegetables a day and consumed more than 30 percent of their calories as fat.

However, while most vegetarians used healthy tactics to check their weight, they were more likely than meat-eaters to have issues with eating and weight control.

Among current vegetarians, about 18 percent said they had problems with out-of-control binge-eating, compared with 5 percent of their peers who'd never been vegetarian. Similarly, 27 percent of former vegetarians admitted to extreme weight-control tactics, versus 15 percent of lifelong meat-eaters.

Robinson-O'Brien noted that parents should also be aware that teenagers run a risk of nutritional deficiencies if their vegetarian diet is not well-planned. She suggested parents ask a doctor or dietitian to help educate their child on proper nutrition and meal planning.