Weight loss on low‐fat vs. low‐carbohydrate diets by insulin resistance status among overweight adults and adults with obesity: A randomized pilot trial. (6th December 2015)

• Record Type: Journal Article
• Authors: Gardner, Christopher D.; Offringa, Lisa C.; Hartle, Jennifer C.; Kapphahn, Kris; Cherin, Rise
• Is Part Of: Obesity. Volume 24:Number 1(2016:Jan.)
• Page Start: 79
• Page End: 86
• Publication Date: 2015-12-06
• Subjects: Obesity -- Periodicals; 616.398005
• DOI: 10.1002/oby.21331
• Languages: English
• ISSNs: 1930-7381

Abstract

Abstract : Objective: To test for differential weight loss response to low‐fat (LF) vs. low‐carbohydrate (LC) diets by insulin resistance status with emphasis on overall quality of both diets. Methods: Sixty‐one adults, BMI 28‐40 kg/m 2, were randomized in a 2 × 2 design to LF or LC by insulin resistance status in this pilot study. Primary outcome was 6‐month weight change. Participants were characterized as more insulin resistant (IR) or more insulin sensitive (IS) by median split of baseline insulin‐area‐under‐the‐curve from an oral glucose tolerance test. Intervention consisted of 14 one‐hour class‐based educational sessions. Results: Baseline % carbohydrate:% fat:% protein was 44:38:18. At 6 months, the LF group reported 57:21:22 and the LC group reported 22:53:25 (IR and IS combined). Six‐month weight loss (kg) was 7.4 ± 6.0 (LF‐IR), 10.4 ± 7.8 (LF‐IS), 9.6 ± 6.6 (LC‐IR), and 8.6 ± 5.6 (LC‐IS). No significant main effects were detected for weight loss by diet group or IR status; there was no significant diet × IR interaction. Significant differences in several secondary outcomes were observed. Conclusions: Substantial weight loss was achieved overall, but a significant diet × IR status interaction was not observed. Opportunity to detect differential response may have been limited by the focus on high diet quality for both diet groups and sample size.