A 24-week randomised controlled trial comparing usual care and metabolic-based diet plans in obese adults

Usual care (UC) practice for weight management often includes providing standardised, ad libitum, low-calorie nutrition plans. However, weight loss using such plans appears comparable with metabolic-based diet (MD) plans that are closer to resting energy expenditure (REE) level. In addition, MD plans are approximately 250-750 kcal/day higher in caloric values compared with UC plans. Therefore, the purpose of this study was to compare weight loss and eating behaviour differences between UC and MD plans.

Seventy-four obese (30.0-51.7 kg/m(2) ) adults (21-67 years) voluntarily participated in a 24-week randomised study. UC men and women received a fixed, ad libitum, 1600 and 1200 kcal/day nutrient plan, respectively. MD participants received an individualised treatment plan based from measured REE. Bodyweight and eating behaviours (i.e. intake, restraint and uncontrolled eating) were assessed over time.

Intent-to-treat analysis indicated no significant difference in weight loss (UC: -5.7 ± 6.3% vs. MD: -5.3 ± 7.1% p = 0.67) between groups over time. There was no difference in daily energy intake (UC: 2490 ± 576 kcal/day vs. MD: 2525 ± 475 kcal/day) at 24 weeks between groups. Both groups experienced a significant improvement (p < 0.05) in eating dietary restraint and uncontrolled eating yet there was no difference between groups.

From this study, UC calorie plans do not generate more weight loss or improve eating behaviours in comparison with MD calorie plans. As treatment effects are comparable, clinicians can select UC or MD plan options based on clinician and patient preference.