NASHVILLE, Tenn. — The gradual introduction of a low-calorie diet was shown to lower hunger hormone levels more significantly when compared with immediate introduction, according to data from a pilot study presented at the ObesityWeek annual meeting.
“Restricting energy intake (eating fewer calories) is critical for weight loss, but maintaining weight loss is very difficult. In part, this difficulty is due to the body’s reaction to energy restriction,” Kristina Lewis MD, MPH, SM, an assistant professor in the division of public health sciences at Wake Forest University Health Sciences, told Endocrine Today. “With weight loss, we typically see increases in a hormone called ghrelin, which stimulates hunger. This is believed to be one of the drivers of weight regain after people finish a diet.”
Lewis and colleagues conducted a 24-week randomized trial with 20 adults aged 18 to 45 years at Wake Forest Baptist Medical Center (75% women; BMI range, 30-39.9 kg/m²). Of the total sample, nine were randomly chosen to gradually decrease caloric intake while the other 11 immediately began a low-calorie diet after 3 weeks of weight stabilization.
In the taper group, caloric intake was decreased roughly 200 kcal per week for 6 weeks until reaching a level of 1,200 kcal per day for men and 1,000 kcal per day for women. After 6 weeks, both groups continued the low-calorie diet until the conclusion of the study at week 24. Participants were able to follow similar dietary patterns by receiving food from Wake Forest Baptist Medical Center, which provided meal replacement shakes and prepared foods at twice-weekly food pickups.
Weight loss, self-reported hunger and fasting ghrelin were all measured at weeks 6, 12 and 24 of the trial. At all three measurement points, weight loss was mostly similar between the two groups, with a slight advantage for those in the immediate diet group. Participants in that group had body weight decreases of 6.8%, 8.9% and 10.2% at weeks 6, 12 and 24, respectively, compared with decreases of 5.8%, 8.4% and 8.1%, respectively, in the taper group.
The immediate diet group also had lower levels of self-reported hunger compared with the taper group at all three measurement points. However, the taper group experienced a significant decrease in fasting ghrelin at 24 weeks (mean, –65.5 ng/pL) compared with those in the immediate group (mean, +103.8 ng/pL; P = .03).
“Even though the main hunger hormone (ghrelin) didn’t rise as much in our caloric ‘taper’ participants as it did in the participants whose calories were dropped abruptly, there was a nonsignificant trend toward taper participants actually self-reporting greater increases in hunger during weight loss,” Lewis said. “We are not certain about why this disconnect between the hunger hormone and perceived hunger would be present.” – by Phil Neuffer
Lewis K, et al. T-P-3200. Presented at: ObesityWeek; Nov. 11-15, 2018; Nashville, Tenn.
Disclosure: Lewis reports this study was supported through an investigator-initiated grant from Nestle Healthcare Nutrition.