Weight loss program is associated with decrease α-tocopherol status in obese adults

Abstract

Background & aims: Studies on changes in plasma α-tocopherol levels during body fat reduction in obese persons are not clear. The aim of the present study was to assess factors associated with α-tocopherol status in obese people and to examine changes in α-tocopherol status after a 6-week AntioxObesity weight loss program.

Methods: The study was conducted in 60 overweight or obese adults, aged 18-54 years old. Food intake data were collected using the 3-day record method and a semi-quantitative food-frequency questionnaire. Anthropometric measurements included: height (H), body weight, waist circumference (WC) and hip circumference (HC), body composition: fat mass (FM) and fat-free mass (FFM), subcutaneous fat (SF) and visceral fat (VF). Lipid profile, α-tocopherol concentration, glutathione peroxidase (GPx) activity, total antioxidant capacity (TAC) in plasma and superoxide dismutase (SOD) activity in erythrocytes were determined.

Results: Energy, fat, and carbohydrate intakes decreased significantly in all subjects (P < 0.001). Body weight, WC, body mass index (BMI), waist-to height ratio (WHtR), and FM, VF and SF decreased significantly during the 6 weeks in all subjects. Plasma α-tocopherol significantly decreased during the program (P = 0.006). No changes were observed for SOD activity, but GPx activity and TAC decreased significantly (P = 0.001; P = 0,023, respectively). Plasma α-tocopherol concentration after 6 weeks of the AntioxObesity program was strongly associated with baseline plasma α-tocopherol, changes in TC, VF and FM. Low α-tocopherol status (<20 μmol/L) was found in 78% of the women and 68% of the men, after 6 weeks of the AntioxObesity program. Men were characterized by a greater decrease in weight, BMI, WC, FM, VF, SF and TAC compared to women.

Conclusions: A 6-week weight loss program lowered α-tocopherol status in overweight and obese people. Low baseline α-tocopherol status and adiposity in obese adults negatively affected α-tocopherol status after 6 weeks weight loss program. These results, coupled with excessive weight and low α-tocopherol intake, led to the finding that there was an increased risk of oxidative stress diseases in adults on a reduced diet. Long-term dietary restriction program for obese patients should be monitored to avoid α-tocopherol deficiency, and take into account higher dietary α-tocopherol requirements for obese people.

Keywords: Adiposity; Obese adults; Weight loss; α-tocopherol status.