Abstract
BACKGROUND: Gender differences in dietary patterns and lifestyle behaviours may influence abdominal adiposity and cardiometabolic risk, but comprehensive analyses integrating these factors remain limited. METHODS: We conducted a cross-sectional study including 1631 adults recruited from a centre specialising in nutrition and metabolic health. Food intake was assessed by 7-day food diaries and lifestyle behaviours were assessed by structured questionnaires. Z scores of a body shape index (zABSI) were calculated as a marker of abdominal adiposity. zABSI represents the standardised value of ABSI, an index specifically designed to assess abdominal adiposity independently of BMI Multivariable linear regression models, stratified by sex and adjusted for age, examined associations between dietary patterns, physical activity and zABSI. RESULTS: Higher intake of plant-based protein was significantly associated with lower zABSI values in women (β = -0.052, p = 0.0053) but not in men (β = -0.015, p = 0.2675). Stratified analyses revealed that women in the middle tertile of plant-based protein intake showed significantly lower zABSI values than men. Combined analyses showed that women classified as physically active and high consumers of plant-based protein had the most favourable abdominal adiposity profiles (p = 0.0036). Participation in endurance and strength sports was associated with lower zABSI values in both sexes, whereas women engaged in team sports had the lowest zABSI values. No significant interaction terms between sex and lifestyle were identified; however, male sex remained an independent predictor of higher zABSI values. CONCLUSIONS: In this cross-sectional study, plant-based dietary patterns and physical activity were associated with lower abdominal adiposity, especially among women. These findings suggest the importance of gender-specific strategies to address cardiometabolic risk and emphasise the need for prospective studies to confirm these associations and clarify the underlying mechanisms.