People who identify themselves as vegetarians fall on a continuum, from those who avoid all animal products (vegans) including milk and eggs, to those who eat fish and/or chicken. Anyone following a vegetarian diet need to pay careful attention to nutritional balance. Some vegetarians may be at risk for deficiencies in specific nutrients including Vitamin B12, calcium, Vitamin D, protein, zinc and certain fatty acids.
They were particularly interested in the possibility that vegetarianism might be a harbinger of or a cover-up for an eating disorder.
A recent study, published in the April issue of the Journal of the American Dietetic Association, evaluated vegetarians and their peers during two time periods, adolescence, ages 15-18, and young adulthood, ages, 19-23. Investigators asked about their motivations, their dietary habits, their weight loss techniques, and their substance use. They were particularly interested in the possibility that vegetarianism might be a harbinger of or a cover-up for an eating disorder.
Researchers collected data from more than two thousand 15-18 year old participants representing 31 schools in Minnesota, and reassessed the same group several years later. They divided the participants into three categories, current vegetarians, former vegetarians (were vegetarian in the past for longer than one month), and never vegetarians. They obtained height, weight, and body mass index (BMI) data and used standardized questionnaires to assess dietary intake and exercise and physical activity habits. Potential eating disorders were explored with questions about binge eating with loss of control and the use of a variety of weight loss strategies. Substance use assessment included cigarettes, beer, wine, hard liquor, marijuana, and other drugs and answers of "a few times or more in the last year" were considered positive.
The researchers thought that there were likely to be some significant differences between adolescent and young adults vegetarians. Adolescents were more likely to be motivated by a desire to establish their own identities and to express their values regarding animals' rights. Additionally, the researchers believed that some adolescents were using vegetarianism as a means to mask an eating disorder in a socially and parentally acceptable way and were using their strict vegetarian standards to control their diet to an unhealthy degree. Young adults who were more likely to be living and eating away from home had less of need for subterfuge and were more likely to make their choices based on personal health or ethical concerns.
The study group was comprised of 108 current vegetarians, 268 former vegetarians and 2112 never vegetarians. Most of the subjects were female. Among the younger group, there was no statistically significant difference in weight between vegetarians and their non-vegetarian peers, but the older vegetarian group had a lower body mass index and members were less likely to be overweight than their never vegetarian peers. This is consistent with other studies that show a significant association between vegetarianism and lower mean body mass in adults.
Significantly, in both the adolescent and the young adult current vegetarian groups, about 20% reported engaging in binge eating with loss of control as compared to 5% of the never vegetarians. Researchers speculate that vegetarians have a heightened awareness of food intake and self imposed restrictions on some protein and fat containing foods lead to a decreased level of satiety (feeling full and satisfied) and a tendency to react by bingeing. The researchers concluded that binge eating is a risk for vegetarians in either age group
In the adolescent group, more current and former vegetarians reported engaging in extremely unhealthful weight control behaviors such as taking diet pills, inducing vomiting using laxatives or diuretics than never-vegetarians. This was less pronounced among the young adults. The researchers concluded that vegetarian adolescents and those most likely to experiment with vegetarianism (former vegetarians) might be at greatest risk for potential eating disorders. This is consistent with other research.
The lessons of this study are that vegetarianism can be a healthy diet when carefully managed, but it can also occasionally be a strategy for masking an eating disorder. Physicians, teachers, and parents should be aware of this potential. Talking with adolescents about their health beliefs, their ethical attitudes towards animals, and their body image concerns may reveal unexpected and important information. Providing adolescent vegetarians with sources of nutritional guidance and making sure they understand the concepts of balanced wholesome diets are important. Helping them develop realistic weight loss plans if they are overweight, and getting proper therapy if they express a distorted view of their appropriate weight are critical parts of parenting adolescents.