title: Loss of body nitrogen on fasting.
abstract: An analysis of the change in total body nitrogen during fasting shows that it declines exponentially, a small fraction being lost rapidly (t 1/2 of a few days), and the remainder being lost slowly (t 1/2 of many months). The obese faster loses N, and weight, at a slower relative rate than the nonobese; and the ratio of N loss to weight loss during an extended fast is inversely related to body fat content, being about 20 g/kg in the nonobese and about 10 g/kg in those with body fat burdens of 50 kg or more. The loss of body N on a low protein-calorie adequate diet can also be described in exponential terms, and this function allows an estimate to be made of the N requirement.
mesh_terms: D000328:Adult; D001835:Body Weight; D004044:Dietary Proteins; D005215:Fasting; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D009584:Nitrogen / Q000378:metabolism*; D009765:Obesity / Q000378:metabolism*
chemical_list: D004044:Dietary Proteins; D009584:Nitrogen