The rate of weight loss does not affect resting energy expenditure and appetite sensations differently in women living with overweight and obesity.

BACKGROUND

Evidence of metabolic adaptations following weight loss is available in the literature. However, the impact of different degrees of caloric restriction on a comprehensive panel including energy expenditure (EE) and intake (EI), appetite, palatability and olfactory performance remains to be investigated. Accordingly, the purpose of the study was to investigate the changes in resting energy expenditure (REE), appetite, olfaction, palatability and EI in women who were engaged in either a slow (-500 kcal/day, 20-week) or in a rapid (-1000 kcal/ day, 10 weeks) weight loss program.

METHODS

Thirty-six women with obesity were randomized to a slow or to a rapid weight loss group. Body composition (DXA), REE (indirect calorimetry), olfactory performance (Sniffin' Sticks), appetite (Visual Analogue Scale) were assessed at multiple time points during the intervention.

RESULTS

A total of 30 participants completed the study (slow group n = 14; rapid group n = 16). Body weight decreased by -4.46 (3.99) % (P < .001) and - 6.23 (3.06) % (P = .001) in the slow and rapid groups, respectively. No differences in % weight loss were noted between groups (P = .175). Significant decreases in fat mass (P < .001), REE (P = .035), total EI (P = .001) were observed over time from both groups. However, no significant differences emerged between groups for any of the outcomes. The satiety quotient (SQ) at time 180 min significantly increased for desire to eat (P = .01), hunger (P = .011) and PFC (P = .002), while the area under the curve for postprandial appetite rates were not changed. No differences in palatability and olfactory performance were noted after the intervention.

CONCLUSIONS

Our results suggest that different rates of weight loss exert similar effects on REE, appetite, satiety, and EI when weight loss are comparable.