Diets with lower carbohydrate concentrations improve insulin sensitivity in women with polycystic ovary syndrome: A meta-analysis.
Level 2 - randomized trial
Meta-analysis pooling pre-post intervention data from prospective studies rather than randomized trial comparator effects
PubMed 32200247 · doi:10.1016/j.ejogrb.2020.03.010
What was done
A systematic review and meta-analysis searched PubMed, SCOPUS, EBSCO, and LILACS through October 2018 for prospective studies evaluating dietary interventions (caloric restriction, altered protein intake, or specialized diets) on insulin resistance in women with polycystic ovary syndrome (PCOS). Pre- and post-intervention HOMA1-IR values were extracted from 20 publications (25 studies) and pooled using random-effects models to calculate standard paired differences (SPD) with 95% confidence intervals.
What was found
Overall, diets significantly reduced insulin resistance (SPD = -0.58; 95% CI: -0.81 to -0.36). Diets decreased IR in 48% of studies, had no effect in 44%, and increased IR in 2 studies. Larger reductions occurred in subjects with severe baseline IR (HOMA1-IR > 4.2: SPD = -1.22; 95% CI: -1.61 to -0.84) and with lower-carbohydrate diets (<50% carbohydrates: SPD = -0.86; 95% CI: -1.23 to -0.50).
Why it matters
This review indicates that dietary interventions, especially lower-carbohydrate diets, improve insulin sensitivity in women with PCOS, with the largest benefit observed in those with severe baseline insulin resistance.
Limits
The total number of participants is not reported in the abstract. Included diets were heterogeneous, and the analysis was based on pre-post paired differences rather than direct comparison against randomized control groups.
Cited by
- supports Temporarily restricting carbohydrates improves insulin sensitivity and glucose disposal in women with type 2 diabetes or PCOS.