Five-year self-management of weight using meal replacements: comparison with matched controls in rural Wisconsin.

We compared 5-y weight changes of subjects after a self-managed meal-replacement weight-control program (MR) with that of matched control subjects in rural Wisconsin. Healthy but overweight females (n = 108) and males (n = 50) received free products and weighed in twice a year from 1992 through 1997. Weights from three area clinics were obtained from 1992 records for 528 healthy males and females, whose weights were again obtained in late 1997. In addition, 1997 weights were obtained on 378 area males and females who reported their 1992 weight by questionnaire. Three control subjects were then selected for each MR participant, matched for age (within 5 y), body mass index (within 2 kg/m(2)), sex, and race. After 5 y, 141 MR participants weighed in, 2 died, and 19 were excluded primarily because of pregnancy. The 50 males were -5.8+/-5.4 kg and the 84 females were -4.2+/-6.9 kg from their 1992 weights. Conversely, 142 matched male controls gained 6.7+/-10.2 kg and 247 female controls gained 6.5+/- 10.7 kg. In conclusion, success determinations of MR and other long-term weight-control programs should be made by comparing changes with matched controls as the background rate of weight gain becomes increasingly more significant the longer the study is run.