Two weeks daily intake of anthocyanin-rich New Zealand blackcurrant extract enhances whole-body fat oxidation during supine rest in healthy males

Introduction: An increase in exercise-induced fat oxidation has been observed with 2-week daily intake of New Zealand blackcurrant (NZBC) extract. We examined for supine rest the effects of 2-week daily intake of NZBC extract on physiological and metabolic parameters in relation to body fat%. Methods: Healthy active men (n=16, age: 24.1±6.0 yr, body mass: 78.2±15.6 kg, BMI: 24.7±4.2 kg·m-2) volunteered. NZBC extract (210 mg of anthocyanins) was consumed with breakfast with 14-day washout. The final ingestion was 2 hours before testing. Physiological and metabolic responses were measured during supine rest (2x10 min) and observations with the lowest 10-min minute ventilation were analysed. Bioelectrical impedance analysis was used to measure body fat%. Results: During supine rest, 14-day daily intake of NZBC extract had no effect on heart rate, minute ventilation, oxygen uptake, carbon dioxide production and energy expenditure. However, 14-day daily intake of NZBC extract decreased the respiratory exchange ratio (baseline: 0.840±0.045, 14-day: 0.820±0.058, P=0.03), increased fat oxidation (baseline: 0.079±0.03, 14-day: 0.088±0.043 g·min-1, P=0.05), and decreased carbohydrate oxidation (baseline: 0.178±0.067, 14-day: 0.143±0.071 g·min-1, P=0.03) during supine rest. Nine of the 16 participants had increased of fat oxidation by more than 10% during supine rest. For those nine participants, the increases were 26±16%. We did not observe a significant correlation between body fat% and absolute and percentual changes in fat oxidation. Conclusions: In a healthy male cohort, daily intake of New Zealand blackcurrant extract for two weeks was able to increase fat oxidation during supine rest. Daily intake of New Zealand blackcurrant extract may be an effective anthocyanin-rich supplement for the management of body composition and body weight.