A role for fruit content in energy-restricted diets in improving antioxidant status in obese women during weight loss

Abstract 

Objective

The aim of the present work was to estimate the ability of two hypocaloric diets with different fruit contents to improve antioxidant biomarkers related to lipid peroxidation in obese women.

Methods

Fifteen obese women (age 32 ± 6 y, body mass index 34.9 ± 2.9 kg/m²) were assigned to two different dietary treatments for 8 wk. The subjects received a hypocaloric diet (600 kcal/d restriction from the measured individual energy expenditure) containing 5% (n = 8) or 15% (n = 7) energy supplied by fructose from fruits. Anthropometric measurements, blood lipid profile, plasma oxidative markers, total antioxidant capacity, and malondialdehyde (MDA) were evaluated before and after the nutritional intervention in addition to some relations among them.

Results

No differences in weight loss were observed between diets (5% energy from fructose in the low fruit diet −6.9 ± 2% versus 15% energy from fructose in the high fruit diet −6.6 ± 2%; P = 0.781). Low-density lipoprotein cholesterol levels significantly decreased (P = 0.048) in obese women who followed the high fruit diet, which was accompanied by a statistical (P = 0.046) diet-related decrease (−30%) in the ratio of MDA to antioxidant capacity. There was a positive association between MDA diet-related change and low-density lipoprotein cholesterol (r = 0.665, P = 0.003), with antioxidant capacity directly proportional to the fiber plus fructose content associated with fruit consumption (r = 0.697, P = 0.025).

Conclusion

A fruit-enriched hypocaloric diet appears to be more effective against oxidative stress. Consumption of antioxidant substances contained in fruit could be a useful strategy in the design of hypocaloric diets that, with the weight reduction, could increase the improvement of cardiovascular risk factors related to obesity.

Keywords:  Obesity , Oxidative stress , Fruit , Caloric restriction , Malondialdehyde , Antioxidant capacity in plasma