Do not use extreme dieting, fasting, or making yourself vomit to control weight. If you want to lose weight, lose it on the exercise side

People with anorexia nervosa (the illness of starving yourself past the point of health) are about 5.9 times as likely to die as people the same age. Follow 1000 of them for 1 year and 5.1 die, and about 1 in 5 of those deaths are suicide. People who diet are more likely to get an eating disorder. Students at 44 secondary schools were followed for 3 years, and girls who dieted severely were 18 times as likely to get ill as girls who did not diet. If you want to control your weight, exercise more. Do not eat so little that you are hungry.

Cost

No money. The other way around, you also save what you would have spent on weight-loss products.

Benefit

36 studies taken together. The people with anorexia nervosa had been followed for 166642 person-years in all (the years each person was followed, added up). Their standardized mortality ratio was 5.86, that is, the chance of death is about 5.9 times that of people the same age. There were 5.1 deaths per 1000 person-years, which means 5.1 deaths if 1000 people are followed for 1 year. About 1/5 of the people who died died by suicide. The standardized mortality ratio for bulimia was 1.93, and for other eating disorders it was 1.92, about 1.9 times people the same age in each case. Another study, in 44 secondary schools in Victoria, Australia, followed students aged 14 to 15 for 3 years, and the same students were checked across 6 rounds. New eating disorders in girls were 21.8 per 1000 person-years, that is, 21.8 new cases if 1000 girls are followed for 1 year. Girls who dieted severely had 18 times the risk of girls who did not diet. Girls who dieted moderately had 5 times the risk. After a further adjustment for past dieting and psychiatric symptoms, taking out the effect of having dieted before and of already having psychiatric symptoms, BMI (body mass index, weight divided by height squared), amount of exercise, and sex no longer predicted a new eating disorder. The authors' conclusion was that "among adolescents, controlling weight with exercise rather than restricting food seems to carry a lower risk of an eating disorder."

Notes

"Severe dieting" here means keeping what you eat far below what the body needs for a long time. It does not mean skipping 1 meal or skipping a late-night snack. If making yourself vomit, guilt after a binge, or weighing yourself over and over and being unable to stop has already appeared, go to a psychiatry department or the clinical psychology department of a general hospital. This is an illness with a standard treatment. It is not a willpower problem. The link between BMI and mortality is in section 2, item 32. That item is about the long-term weight range, not about the method of losing weight.

Sources · 2

1. Arcelus J et al. (2011). Mortality rates in patients with anorexia nervosa and other eating disorders. A meta-analysis of 36 studies. Arch Gen Psychiatry. doi.org/10.1001/archgenpsychiatry.2011.74
2. Patton GC et al. (1999). Onset of adolescent eating disorders: population based cohort study over 3 years. BMJ. doi.org/10.1136/bmj.318.7186.765