[Slimming behavior among Danes assessed by telephone interviews in 1992 and 1998]

With the increasing prevalence of overweight and obesity, it is assumed that slimming is on the increase. The aim of the present study was to elucidate the prevalence of slimming attempts, the methods used, and whether the weight loss was maintained.

Two independent telephone interviews were conducted in 1992 and in 1998. About 1200 adults selected at random were entered in each survey in a balanced design, which ensured an equal distribution of age, gender, and geographical regions in Denmark.

The prevalence of obesity increased from 10% to 13% between 1992 and 1998. The proportion of subjects who had been slimming at least once in their lives increased from 45% to 47%, with a distribution of 25% in the underweight, 38% in those of normal weight, 54% of the overweight, and 76% of the obese (p < 0.0001). The use of anti-obesity medicine on prescription and support by a primary care physician or dietician increased with increasing body mass index. Subjects who chose to change their diet or increase their physical activity were more successful in achieving and maintaining a weight loss than those who did not. Changes in diet rose significantly from 1992 to 1998, whereas the use of prescription medicine and over-the-counter protein formulas and supplements decreased. The use of prescription medicine by subjects of normal weight decreased from 11% to 2%.

About half of all adult Danes have been on a slimming diet. Those who choose to change their diet or increase physical activity are more successful in achieving a weight loss and maintaining it. Notably, one in four underweight subjects have been on a slimming diet, and one in four obese subjects have never dieted, particularly obese males. The use of prescription slimming compounds by individuals of normal weight seems to be a decreasing problem.