Postprandial energy expenditure of protein is affected by its phosphorus content

Postprandial energy expenditure (PEE) is largely dependent on ATP production, which is may be affected by phosphorus (P) availability. Proteins are known to have high levels of P and induce high levels of PEE. This study aimed at assessing the effect of P in PEE of normal and high protein meals. A single-blind randomized crossover study was conducted with two groups of 12 healthy lean male subjects who received iso-caloric (554 Kcal) meals. Group1: normal protein (NPr) meal with or without P (500 mg) and group 2: high protein (HPr) meal with or without P (500 mg), on two visits separated by a minimum of 1-week washout period. Energy expenditure and substrate oxidation were measured at baseline and every 30 min for 4 h after meal ingestion using a ventilated hood for indirect calorimetry. NPr and HPr meals had similar postprandial energy expenditure and this was significantly increased (P = 0.005) by P ingestion. Our work shows that PEE of protein meal is highly affected by P content of the meal.