Improved nutrient intake in older obese adults undergoing a structured diet and exercise intentional weight loss program.

Abstract

Physicians are often reluctant to advise older obese patients to lose weight for fear of compromised nutrition and excessive loss of muscle mass and strength, all of which may lead to a loss of independence and accelerate disability. Therefore, the purpose of this study was to examine nutrient intake in older obese adults undergoing a weight loss intervention. The study setting was at a university research facility. A total of 71 participants (age, 69.5 (SD = 5.8) yrs; 62% female; BMI, 34.6 (4.4) kg/m2) were recruited. Individuals were randomized into either a weight stable (WS) control group or an intensive weight loss (WL) group. The WL intervention was for 6 months and utilized partial meal replacements (PMR) and a facility-based 3 d/wk, 60 min/session exercise training program encompassing both aerobic and strength exercises. Weight loss goal for WL was 10% from baseline at 6-months. Variables were obtained at baseline and 6-months and included 3 day dietary records along with daily step counts for 7 days. Total energy, macronutrients (g and % of energy), micronutrients (vitamins and minerals), as well as use of PMR were assessed from the diet records. Body mass and body fat (g and % of body mass) were determined at the 2 time points. Estimated marginal means (SEM) for weight loss at 6-months was -8.8 (0.7)% for WL and -0.1 (0.7)% for WS. Daily energy intake at 6-months was lower for WL (1396 (64) kcals) compared to WS (1817 (71) kcals). Additionally, those in the WL group (compared to WS) had lower intakes of total fat (27.5 (1.2)%, WL vs. 36.1 (4.6)%, WS) and saturated fatty acids (8.5 (0.4)% vs. 10.8 (0.5)%), and had higher levels of carbohydrates (57.6 (1.5)% vs. 49.0 (1.7)%), protein (18.4 (0.5% vs. 16.2 (0.6)%), and dietary fiber (21.0 (0.9) g vs. 17.4 (1.0) g) at 6-months. Even with reduced total calorie intake, key micronutrients (calcium, iron, vitamin D, vitamin E, vitamin C) were higher for WL vs. WS at 6-months. Total daily step counts were higher for WL vs. WS at 6-months. A nutrition intervention to promote weight loss in older obese adults was achieved using PMR as a primary strategy. Diet quality was improved for WL vs. WS in using the nutrient fortified product, even with a reduction in total energy intake.