Effect of time-restricted feeding on body composition and cardio-metabolic risk in middle-aged women in Taiwan

Abstract

Objectives: We sought to investigate the effects of time-restricted feeding (TRF) and a traditional weight-loss method on body composition and cardio-metabolic risk factors in middle-aged women.

Methods: In a single-center, randomized, open-label, parallel-group design, women ages 40 to 65 y with body mass index ≥ 24 kg/m² or waist circumference > 80 cm were recruited. They were guided to a daily low-calorie diet of 1400 kcal and randomly assigned into a TRF group (limit 8 h of eating time and fasting for 16 h) or a non-TRF group (traditional weight-loss method, unrestricted eating time) for 8 wk. Body composition, blood pressure, blood biochemical variables, and insulin resistance status were measured before and after intervention.

Results: Body weight, body mass index, waist circumference, and body fat mass decreased significantly in both groups after 8 wk of intervention (P < 0.05). Body weight decreased more in the TRF group than the non-TRF group (-4.1% ± 2.8% versus -2.4% ± 2.5%; P = 0.012), as did diastolic blood pressure (75.3 ± 11.2 mm Hg versus 70.5 ± 9.4 mm Hg; P = 0.012). There were no statistical differences between the two groups in total cholesterol, triacylglycerols, high- or low-density lipoprotein cholesterol, and fasting insulin level. However, fasting glucose and insulin resistance status increased significantly for the TRF group after the intervention (respectively, 88.3 ± 7.6 mg/dL versus 92.6 ± 9.6 mg/dL, P = 0.003; 1.7 ± 0.7 versus 2.1 ± 1.0, P = 0.048).

Conclusion: The weight loss and reduction in diastolic blood pressure using the TRF method were better than with the traditional weight-loss method. However, this method may increase fasting glucose levels and adverse insulin resistance status.

Keywords: Body composition; Cardio-metabolic risk factors; Time-restricted feeding.