 | Protein-Energy Requirements of Developing Countries: Evaluation of New Data (United Nations University - UNU, 1981, 268 pages) |
 |  | Obligatory nitrogen losses-adults |
| | Obligatory nitrogen losses of adult Thai males |
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Experimental details
1. Subjects
Four male adult Thais 21 to 25 years old.
Their body weights were 45 to 67.5 kg, and their heights were 164.5 to 169 cm.
They were healthy and well-nourished, based on medical history, physical
examination, urinalysis, stool examination, chest x-ray, and a routine complete
blood count.
2. Study Environment
The entire study was conducted at
the clinical research ward (a metabolic unit) in
Ramathibodi Hospital. The climatic characteristics were those of tropical countries.
3. Physical Activity
The subjects were allowed to
continue their usual activities but were not allowed to participate in
competitive, active sports.
4. Duration of the Study
The study of obligatory
nitrogen losses was carried out over a 14-day period.
TABLE 1. Composition of the Protein-Free Diet
| Ingredients | g/day |
| Mung bean starch | 100.4 |
| Mung bean noodles | 100.0 |
| Sugar | 1 08.6 |
| Margarine | 48.0 |
| Oil | 30.0 |
| Onion leaf | 30.0 |
| Wax gourd | 27.0 |
| Salt | 5.1 |
| Lemon juice | 2.4 |
| Soy sauce | 2.0 |
| Garlic | 2.0 |
| Carbonated beverage | variable |
5. Diets
The composition of the protein-free meal is
shown in table 1. The subjects were given four meals per day at 7.30 a.m., 12
noon, 5.00 p.m., and 9.30 p.m. Daily energy intakes were constant, at about 45
kcal/kg/day. Fat provided approximately 30 per cent of the daily energy intake.
Multivitamin and mineral tablets were given twice each day. Water was offered ad
libitum but the volume was recorded daily.
6. Indicators and Measurements
- Total nitrogen in urine and faeces was measured by a calorimetric semi-automated procedure (Munro and Fleck, Mammalian Protein Metabolism, vol. 3 [1969]). Nitrogen balance was calculated from the last five and ten days of urinary and faecal nitrogen losses, respectively.
- Basal metabolic rate (BMR) was measured at seven-day intervals with a respirometer (closed circuit).
- Body weight was recorded daily.
- Serum concentrations of total protein, albumin, urea nitrogen, and some amino acids and amino transferase activities were measured at seven-day intervals.
TABLE 2. Obligatory Nitrogen Losses in Four Adult Thai Males
| Subject | U | F | S | Total |
| M.P. | 38.6 | 15.1 | 5 | 58.7 |
| V.D. | 32.5 | 12.4 | 5 | 49 9 |
| S. R. | 33.4 | 12.4 | 5 | 50.9 |
| S.S. | 35.0 | 10.6 | 5 | 50.6 |
| Mean ± S.D. | 34.9 ± 2.7 | 12.6 ± 1.9 | 5 ± 10 | 52.5 ± 4.2 |
U = urinary nitrogen losses, average from the last 5 days of 14-day dietary period.
F = faecal nitrogen losses, average from the last 10 days.
S = skin and other minor route nitrogen losses, taken from FAD/WHO.
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