Diet-induced thermogenesis (DIT) is believed to be largely related to ATP production, which is dependent on phosphorus (P) availability. We aimed to test the effect of P addition on DIT of lean and overweight/obese healthy subjects. DIT was measured with or without P in 10 lean and 13 overweight/obese adults in a double-blind randomized cross-over pilot study with one week washout period. After 10 h overnight fast, resting metabolic rate, respiratory quotient, and substrate utilization were measured at fasting and every 30 min for 3 h after subjects drank a standardized glucose solution, with P (500 mg) or placebo pills. Subjective ratings of hunger and satiety were assessed before and after the end of each experiment using validated visual analogue scale (VAS) questionnaires. Overweight/obese subjects had a blunted DIT with placebo, while P supplementation induced a 23% increase in their DIT area under the curve (p < 0.05), which was associated with a significant increase in carbohydrate oxidation. Subjects had lower appetite following P supplementation, which was expressed as a significantly (p = 0.02) lower desire to eat a meal (4.0 ± 0.7 cm) compared with placebo (5.8 ± 0.9 cm). P supplementation recovers the blunted diet-induced thermogenesis in overweight and obese subjects and enhances their postprandial satiety.
Keywords: diet induced thermogenesis; energy balance; energy expenditure; obesity; phosphorus; supplementation.