Short-Term Energy Restriction Leads to Overall Increase in Appetite

Among young women, short-term energy restriction was found to result in overall increased appetite mediated by weight loss, according to the results of a study presented at the 30th Annual Scientific and Clinical Congress of the American Association of Clinical Endocrinologists (ENVISION 2021).

This study included 19 healthy women (aged 23.36±2.08 years) with a body mass index (BMI) of 23.15±2.34 kg/m². Menarche occurred between the ages of 11 and 14 years, and all women experienced regular menstrual cycles (25-35 days). The study interventions included a 5-day diet and exercise program during the early follicular phase of 2 cycles of menstruation. They were:

• Neutral energy availability (NEA): 45 kcal/kg lean body mass (LBM) per day

• Deficient energy availability (DEA): 20 kcal/kg LBM per day

On day 5 of these interventions, fasting body composition measures were assessed, fasting and serial metabolic hormone measurements were obtained, and study participants were provided with a fasting visual analog scale (VAS) appetite questionnaire. The outcome variable included items from the VAS appetite questionnaire (scores for appetite, satiety, hunger, and craving), with body weight, fasting leptin, and fasting orexin-A treated as mediating factors. VAS appetite questionnaire items, body weight, and fasting hormone levels were compared between NEA and DEA using paired t-tests. The effects of changes in leptin, body weight, and orexin-A on satiety, appetite, hunger, and craving were examined using linear regression models.

The effects of short-term (4-day) energy restriction included a substantial increase in appetite (55% to 76%; P <.001) and a decrease in both satiety (42% to 19%; P <.01) and craving (49% to 38%; P <.01). This energy restriction also led to a 1-kg decrease in body weight (P <.001), a decrease of 0.5 kg/m² (P <.001) in BMI, a decrease of 3.13 ng/mL in fasting leptin (P <.01), and an increase of 0.06 ng/mL (P <.05) in fasting orexin-A. A negative change in fasting leptin was predictive of a positive change in appetite and a negative change in satiety (P <.05), although controlling for body weight removed this predictive power. Change in appetite was not predicted by a positive change in fasting orexin-A. A decrease in body weight also predicted increased appetite, an effect not mediated by leptin, which suggests other factors like ghrelin could be mediators.

The researchers concluded that “short-term [energy restriction] results in an increase in appetite that is mediated by weight loss both independently and through decreased leptin.” Furthermore, “the effect of short-term [energy restriction] on specific food cravings is overwhelmed by the overall increase in appetite,” which supports “emphasizing appetite control early on in weight loss programs.”

Reference

Okigbo C, Tessa Tonleu J, Shekhar S, et al. The effect of short-term energy restriction on appetite. Presented at: 2021 AACE Virtual Annual Meeting, May 26-29, 2021.