TOPLINE: 

An exploratory analysis of data from a clinical trial found that both intermittent fasting plus time-restricted eating (iTRE) and calorie restriction (CR) resulted in similar weight loss in adults with obesity over 6 months. However, CR led to a greater increase in dietary restraint and reductions in disinhibition, compared with iTRE, with changes in disinhibition mediating 15% of CR's weight loss effect.

METHODOLOGY:

• Researchers conducted an exploratory analysis of data from a clinical trial to compare the effects of iTRE and CR on eating behavior, mood, sleep, and quality of life in adults with obesity.
• A total of 209 adults (mean age, 58 years; 57% women; mean BMI, 34.8) with obesity with an elevated risk for type 2 diabetes were randomly assigned to either iTRE intervention (n = 85), CR intervention (n = 83), or standard care (SC; n = 41).
• Members of the iTRE group were instructed to consume 30% of their calculated baseline energy requirements from a prescribed menu — including two meal replacements at breakfast (around 8 AM) and lunch (around noon) — on fasting days, followed by a 20-hour fast starting at noon on three nonconsecutive fasting days per week. On non-fasting days, iTRE group members were instructed to consume their regular diet. Study participants in the CR group were prescribed a daily 30% calorie reduction from their calculated baseline requirements; SC group members received healthy eating guidelines in a booklet form, without additional counseling or meal replacements. Only the iTRE and CR groups received diet counseling during the first 6 months.
• Changes in eating behaviors were assessed using the Three-Factor Eating Questionnaire (measuring dietary restraint, disinhibition, and hunger); mood, sleep quality, food addiction symptoms, psychological distress, and quality of life were measured at baseline and 2, 6, and 18 months.
• A mediation analysis was performed to examine whether changes in dietary restraint or disinhibition mediated the weight loss effects at 2 and 6 months.

TAKEAWAY:

• At 2 and 6 months, both the iTRE and CR groups experienced significantly greater weight loss from baseline than the SC group (estimated change from baseline at month 6: iTRE: -7.38 kg; CR: -6.99 kg; SC: -2.44 kg; P < .001); weight loss was comparable between the iTRE and CR groups (at month 6, P = .47).
• The CR group had significantly greater increases in dietary restraint than the iTRE and SC groups at months 2, 6, and 18 (P = .003,.0004, and.001, respectively) as well as greater reductions in disinhibition at month 6 (P = .001) and greater reductions in hunger at month 6 (P = .04).
• The mediation analysis found that only the reduction in disinhibition accounted for 15.0% (95% CI, 4.5%-32.9%) of the treatment effect on weight loss in CR vs SC (P < .001), while no detectable mediation effect was found for dietary restraint in either iTRE or CR, or for disinhibition in iTRE.
• No significant between-group differences were observed in reductions in the severity of depression and anxiety and in improvements in sleep quality and most quality-of-life measures.

IN PRACTICE:

"Both active interventions resulted in clinically relevant weight loss accompanied by improved eating behaviors," the authors wrote. "Whilst greater improvement in eating behavior was observed with CR, this did not translate into more weight loss. An exploratory mediation analysis suggested that iTRE and CR may exert effects on body weight through distinct behavioral pathways, with disinhibition playing a more prominent role in daily CR based strategies."

SOURCE:

This study was led by Xiao Tong Teong, School of Medicine, Adelaide University, Australia. It was published online in Clinical Nutrition.

LIMITATIONS:

The study had a relatively small sample size. Social factors such as education level, marital status, social support, and self-efficacy were not examined. The SC group was also highly self-motivated, with some participants achieving significant weight loss, possibly affecting group comparisons. 

DISCLOSURES:

This study was supported by the National Health and Medical Research Council Project Grant. One author reported receiving research support through an Australian Government Research Training Program Scholarship from The University of Adelaide. The authors declared no conflict of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.