Effects of a behavioral weight-loss program food purchases: instructions to shop with a list

Effects of instructions to shop with a list on subsequent food purchases were evaluated in the context of a 12-week behavioral/nutritional weight loss program. In the fifth class, subjects were taught to prepare a weekly menu, convert the menu to a shopping list, adjust the list for foods already on hand and organize the list to be consistent with supermarket layout. Subjects were told to attempt to restrict their purchases to items and amounts on the list. Food purchases were reduced from 16,188 kcal per person per week prior to the shopping class to 9625 kcal during the remainder of the treatment period in five subjects losing greater than or equal to 4.5 kg during treatment and from 14,620 kcal to 12,305 kcal for five subjects losing less than 4.5 kg during the treatment. The decrease for subjects losing less than 4.5 kg did not reach significance, but a further decrease to 10,254 kcal during follow-up was significantly less than pre-intervention purchases. Reductions posted by the greater than or equal to 4.5 kg subjects were maintained over a 12-week post-treatment follow-up period. A non-equivalent control group of six shoppers who were not attempting to lose weight did not change over the same time period, (averaging 14,470, 14,939 and 12,636 kcal at pre-intervention, post-intervention and follow-up respectively), ruling out seasonal factors as an alternative explanation. Food purchases were also analyzed for qualitative changes.