Dietary consequences of recommending reduced-fat dairy products in the weight-loss context: a secondary analysis with practical implications for registered dietitians.

Replacing full-fat dairy products with reduced-fat varieties is a dietetic strategy for reducing energy intake while maintaining nutritional adequacy. This study aimed to explore the dietary outcomes of this recommendation in the context of weight loss. This study involved a secondary analysis of diet-history data for 86 adults (23 males and 63 females; body mass index=31.1±3.4) who had completed 3 months of a weight-loss trial in 2009, including advice to consume reduced-fat dairy products. Dairy food intake was categorized using the Australian 1995 National Nutrition Survey food hierarchy. Paired t tests and Wilcoxon signed rank tests determined dairy product consumption change after dietetic intervention. Total fat and energy per day from dairy products decreased significantly, from 14.1±1.2 g to 5.8±0.6 g and 283±20 kcal to 223±14 kcal, respectively, and total carbohydrate from dairy products increased significantly (P=0.04). Only 19.7% of participants met their dietary target of two to three servings of dairy foods per day at 3 months. When analyzed by sex, males decreased their intake of dairy products significantly, from 377.63±62.3 g/day to 357.3±46.7 g/day. Despite consuming less fat from dairy products, females did not significantly reduce energy intake from these foods (P=0.05). This study indicated that men and women responded differently to advice to change from regular to reduced-fat dairy products. Of more concern, however, is that in a weight-loss context, both men and women might choose to consume fewer servings of this food category with significant nutritional implications. Overall, this research highlights the need to consider the impact of sex and the background diet when recommending reduced-fat dairy products in the weight-loss context.