TABLE 1.
Nutritional composition (energy content and macronutrient composition) of the daily low- and high-protein diets for a participant with an energy intake of 11 MJ/d and a body weight of 68 kg1
| Low-protein diet | High-protein diet | |
| Energy (MJ) | 10.7 | 11.4 |
| Protein (g/kg body weight) | 0.5 | 1.9 |
| Protein [g (% of energy)] | 31 (5) | 127 (19) |
| Carbohydrates [g (% of energy)] | 353 (56) | 303 (45) |
| Fat [g (% of energy)] | 108 (37) | 106 (34) |
| Alcohol [g (% of energy)] | 5 (1) | 6 (2) |
| Fiber (g) | 30 | 31 |
Duplicate portions of the provided diets were collected every day for an imaginary participant, stored at −20°C, and analyzed for energy and macronutrient composition after the experiment. Nitrogen was determined by the Kjeldahl method (27; method 920.87), and the amount of protein was calculated by using a conversion factor of 6.25. Fat was determined by the acid hydrolysis method (27; method 14.019), and available carbohydrate was calculated by subtracting moisture, ash, protein, dietary fiber, and fat from total weight. Energy content was calculated from the macronutrient composition by using the following energy conversion factors: protein, 17 kJ/g; fat, 37 kJ/g; carbohydrate, 17 kJ/g; alcohol, 29 kJ/g. The average of the calculated composition of the free-choice items (10%), which were recorded in a diary by all participants (n = 37), was added.