This narrative review aims to synthesise current evidence of the effects of different dietary patterns on insulin sensitivity in individuals with overweight or obesity, highlighting the underlying mechanisms and clinical implications.
A literature search was conducted in PubMed and Scopus between October 2024 and January 2025, using keywords including “dietary pattern,” “insulin sensitivity,” “insulin resistance,” “overweight” and “obesity.” Of the initially identified articles, eight human studies, comprising randomised controlled trials, cohort and cross-sectional designs, met the inclusion criteria and were included in the final synthesis.
The selected studies demonstrated that several dietary patterns, namely, very low-carbohydrate, Mediterranean, dietary approaches to stop hypertension, plant-based, low-fat and low-glycemic index diets, consistently improved insulin sensitivity through diverse mechanisms. These include reductions in visceral adiposity, modulation of gut microbiota and short-chain fatty acid production, improved lipid profiles and decreased oxidative stress and inflammation. Very low-carbohydrate diets showed the most immediate effects, while Mediterranean and plant-based diets provided broader cardiometabolic benefits over time.
Given the limited number and variability of studies, further long-term, diverse-population trials are needed.
These findings have practical implications for personalised nutrition counselling in clinical settings, guide public health recommendations to prevent metabolic disease and support culturally sensitive nutrition education programs. Promoting adherence to nutrient-dense, whole-food dietary patterns has the potential to reduce the burden of insulin resistance and related complications on both individual and societal levels.
This review synthesises recent human studies on dietary interventions targeting insulin resistance in overweight and obese populations. While each dietary pattern offers distinct metabolic benefits, common features such as high fibre intake, low refined carbohydrates and anti-inflammatory properties emerge as consistent contributors to improved insulin sensitivity. Given the limited number and variability of studies, further long-term, diverse-population trials are needed.
