16-Week Supplementation With a Mediterranean Diet-Inspired Ingredient Rich in a Diversity of Polyphenols Improves Health-Related Quality of Life of Overweight and Obese Volunteers: A Randomized, Double-Blind, Parallel Clinical Trial

Overweight and obesity adversely affect health-related quality of life (HRQOL) through day-to-day impairments of both mental and physical functioning. It is assumed that polyphenols within the Mediterranean diet may contribute to improve HRQOL. This investigation aimed at studying the effects of a polyphenol-rich ingredient on HRQOL in overweight and obese but otherwise healthy individuals. A randomized, double-blind, placebo-controlled study including 72 volunteers was conducted. Subjects were randomly assigned to receive for a 16-week period either 900 mg/day of the supplement or a placebo. Dietary recommendations were individually determined, and intakes were recorded; daily physical mobility was monitored. Improvement of HRQOL was set as the primary outcome and assessed at baseline and at the end of the investigation, using the Short-Form 36 (SF-36) Health survey. Body composition was analyzed using dual-energy X-ray absorptiometry (DXA). Physical activity level was calculated using International Physical Activity Questionnaire (IPAQ). After 16 weeks, despite there was no adherence to the Mediterranean Diet Serving Score (MDSS), supplemented individuals experienced significant HRQOL improvement (+5.3%; P=0.001), including enhanced perceived physical (+11.2%; P=0.002) and mental health (+4.1%; P=0.021) components; bodily pain, vitality, and general health, being the greatest contributors. Besides, body fat mass significantly decreased (-1.2 kg; P=0.033), mainly within trunk area (-1.0 kg; P=0.002). Engagement in physical activity significantly increased (+1308 Met-min/week; P=0.050). Hence, chronic supplementation with a nutritional diversity and dose of a Mediterranean diet-inspired polyphenol-rich ingredient resulted in a significant amelioration in both perceived physical and mental health, concomitant with the improvement of body composition, in healthy subjects with excessive adiposity.