Phosphorus supplementation recovers the blunted diet induced thermogenesis in overweight and obese subjects

Diet induced thermogenesis (DIT) of obese subjects was reported to be blunted or lower than that of lean subjects (Ravussin & Swinburn, 1996). We have previously found that phosphorus (P) supplementation increases DIT of glucose solution in healthy lean subjects (Bassil et al , 2013) probably due to an increase in postprandial ATP production. A study was conducted to investigate whether P supplementation is able to stimulate DIT of overweight and obese subjects. DIT of glucose solution was measured with or without P in 12 overweight and obese subjects (4M, 8F; Age=22.4±1.2y; BMI= 30.3 ±0.9kg/m 2 ) in a double‐blind cross over design with 1 week washout period. After a 10‐h overnight fast, subjects drank a standardized 296mL solution containing 75g glucose, with P (500mg) or placebo pills. Oxygen consumption (VO 2 ) was measured every 30 min for 3 hours using an indirect calorimeter to derive energy expenditure. Baseline fasting resting metabolic rate (RMR) and VO 2 did not differ between the 2 experiments (p=0.4). In line with the literature, DIT of overweight and obese subjects was blunted with placebo, whereby VO 2 did not change from baseline after the consumption of glucose solution. Conversely, P supplementation was associated with a significant increase (p<0.05) in VO 2 during the first 90 min (320±17 mL/min) compared with baseline (297±10 mL/min) which was equivalent to a 10% increase in DIT from baseline. In conclusion, P supplementation recovers the blunted DIT in overweight and obese subjects. These results highlight the important role of P in energy balance in obesity. Further studies are warranted to elucidate the long term effects of P supplementation and to explore potential mechanisms of action.