Examining differences between overweight women and men in 12-month weight loss study comparing healthy low-carbohydrate vs. low-fat diets

Abstract

Background/objectives Biological sex factors and sociocultural gender norms affect the physiology and behavior of weight loss. However, most diet intervention studies do not report outcomes by sex, thereby impeding reproducibility. The objectives of this study were to compare 12-month changes in body weight and composition in groups defined by diet and sex, and adherence to a healthy low carbohydrate (HLC) vs. healthy low fat (HLF) diet. Participants/methods This was a secondary analysis of the DIETFITS trial, in which 609 overweight/obese nondiabetic participants (age, 18–50 years) were randomized to a 12-month HLC (n = 304) or HLF (n = 305) diet. Our first aim concerned comparisons in 12-month changes in weight, fat mass, and lean mass by group with appropriate adjustment for potential confounders. The second aim was to assess whether or not adherence differed by diet-sex group (HLC women n = 179, HLC men n = 125, HLF women n = 167, HLF men n = 138). Results 12-month changes in weight (p < 0.001) were different by group. HLC produced significantly greater weight loss, as well as greater loss of both fat mass and lean mass, than HLF among men [−2.98 kg (−4.47, −1.50); P < 0.001], but not among women. Men were more adherent to HLC than women (p = 0.02). Weight loss estimates within group remained similar after adjusting for adherence, suggesting adherence was not a mediator. Conclusions By reporting outcomes by sex significant weight loss differences were identified between HLC and HLF, which were not recognized in the original primary analysis. These findings highlight the need to consider sex in the design, analysis, and reporting of diet trials.

Association between weight change and remission of type 2 diabetes: a retrospective cohort study in primary care

“…In our cohort, females were more likely than men to achieve remission. This finding is consistent with previous studies and may be due to greater motivation in females to lose weight as a result of greater dissatisfaction with weight, stronger preference for lower fat diet, and societal pressure for them to be slim 17,18 . Older people and those with fewer comorbidities were also more likely to achieve remission.…”

Evaluation of Measured Resting Metabolic Rate for Dietary Prescription in Ageing Adults with Overweight and Adiposity-Based Chronic Disease

“…Strong adherence level is associated with successful outcomes in weight management [ 61 ]. A recent study investigating sociocultural gender factors which influence food behaviours, such as dietary preferences and adherence, reported that men were more adherent to a healthy low-carbohydrate (HLC) than women ( p = 0.02) vs. healthy low-fat (HLF) diet [ 62 ]. Another possible reason for this may be the addition of regular one-to-one support provided by the researcher, where goal setting and self-monitoring of food intake were encouraged using motivational interviewing techniques and behavioural change skills.…”

“…A secondary analysis of data for biological sex differences in weight variation within the mRMR and eRMR groups, or other sex-related factors, such as genotype, hormones, metabolic syndrome, or psychosocial factors that may affect either adherence to dietary intervention or weight reduction response were not investigated. Aronica et al [ 62 ] highlighted the need for such analysis while acknowledging that a limited amount of weight reduction studies demonstrated sufficient power to compare the effects of energy restriction diets on weight outcomes in women vs. men. The present study duration was 12 weeks, thus it is unknown whether participants in the mRMR or eRMR groups maintained weight reduction over a longer period.…”

“…Future research is needed to better understand the efficacy of RER and substrate utilisation information in tailoring dietary prescription. To address the gap in the literature as identified by Aronica et al [ 62 ] biological sex differences such as body composition and metabolism should be investigated among research participants to compare the effects of diets with energy prescription based on IC or prediction equations on weight outcomes. Furthermore, sociocultural gender factors which influence food behaviours such as dietary preferences and adherence should be explored.…”

Tagesklinische Versorgungsstruktur zur Komplextherapie der Adipositas III°

“…Neben Präventionsmaßnahmen existieren verschiedene konservative und bariatrische Therapieoptionen, die in den S3-Leitlinien "Prävention und Therapie der Adipositas" und "Chirurgie der Adipositas und metabolischer Erkrankungen" dargelegt werden [7,10]. Basierend auf den Empfehlungen der S3-Leitlinie "Chirurgie der Adipositas und metabolischer Erkrankungen" stellt die tiven Adipositastherapie hinweisen, deren zugrunde liegende Mechanismen nicht ausreichend verstanden sind [19,20]. Die oben zitierten Studien zeigen eindrucksvoll, dass weniger die Gewichtsreduktion, sondern vielmehr die langfristige Stabilisierung ein wichtiges Problem insbesondere der nichtchirurgischen Adipositastherapie darstellt.…”