The association between total antioxidant capacity and resting metabolic rate (RMR) / respiratory quotient (RQ) in overweight and obese woman

Abstract

Objective: The effect of total antioxidant capacity on resting metabolic rate (RMR) and respiratory quotient (RQ) of overweight and obese woman has been debated globally. Total Antioxidant Capacity may have an independent effect on resting metabolic rate and respiratory quotient.

Methods and materials: A study population of 263 aged 18-50 years participated in this cross-sectional study from the communities of Tehran based on cluster sampling. Dietary intake assessed by using a semi quantitative food frequency questionnaire (FFQ) Demographic questions. Anthropometrics measurements for each participant were done. Dietary total antioxidant capacity (DTAC) was calculated by the 147-item food frequency questionnaire (FFQ) and FRAP assay. Resting metabolic rate and respiratory quotient was measured by Indirect calorimetry.

Results: The mean DTAC of the study participants was 1251.8 (SD 893.60). There was a statistically significant relationship between dietary total antioxidant capacity (DTAC) and respiratory quotient (P > 0.013). People with high dietary total antioxidant capacity have tended to show a lower RQ than those with a lower one. There was a significant correlation between DTAC and RQ for both the adjusted model for age, total energy intake, BMI, physical activity, higher DTAC diet and the crude model which were (β = 0.011; SE = 0.005; CI = -0.021_0) and (β = -3.143E-6; SE = 0; CI = 0), respectively. However, we found no correlation between the DTAC and RMR/FFM-RES (P < 0.49). Also, a significantly higher relationship was demonstrated between dietary total antioxidant capacity and intake vegetables (P ≤ 0.006), fruits (P ≤ 0.009), white meet (P ≤ 0.03) and dairy products (P ≤ 0.005).

Conclusion: RQ is correlated with total antioxidant capacity. Increased intake of high DTAC foods may result in weight loss maintenance. This result may suggest a beneficial role of higher-DTAC diets in the prevention of obesity.

Keywords: Body composition; Body fat mass; Fat-free mass; Obesity; Overweight; Respiratory quotient; Resting metabolic rate; Total antioxidant capacity.