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30. Absorption of macronutrients during the acute stage and after recovery from diarrhoea of different aetiologies
31. The effect of dietary fibre on digestibility of nutrients in a typical chilean diet
32. Protein digestibility of common beans: the role of polyphenolic compounds
33. The study of experimental protein deficiency
34. The growth velocity of adolescent girls
35. Accelerated recovery from undernutrition in children attending a food programme

30. Absorption of macronutrients during the acute stage and after recovery from diarrhoea of different aetiologies

A.M. Molla

International Centre for Diarrhoeal Disease Research, Dacca-2, Bangladesh

Objectives

The aim of this study was: (a) to make a quantitative estimation of the intake and absorption of food during diarrhoea. two and eight weeks after recovery, and (b) to compare the intake and absorption of macronutrients, e.g. calories, carbobydrate, fat and nitrogen in diarrhoea of different aetiologies in patients with diarrhoea associated with cholera, rotavirus infection, enterotoxigenic E Coli (ETEC), and Shigella. Patients were offered standard, familiar food after rehydration and during recovery. Samples were analysed from each type of food, and from faeces and urine for the determination of calories, fat, and nitrogen. The coefficient of absorption of calories during the acute stage of cholera. rotavirus, ETEC, and Shigella was 81, 55, 88, and 68 per cent respectively, and of nitrogen 42, 45, 58, and 41 per cent respectively. It was noted that 52 per cent of patients with cholera, 54 per cent with ETEC, 79 per cent with rotavirus, and 33 per cent with Shigella were in positive nitrogen balance. Two weeks after recovery nearly 90 per cent of the patients in all categories were also in positive nitrogen balance. The results of this study indicate that, even during the acute stage of diarrhoea, the majority of patients can eat and absorb substantial amounts of food and remain in positive nitrogen balance when food is offered.

Methods

Patient Selection

Sixty-three male children under five years of age, with a short history of acute, watery diarrhoea and moderate to severe dehydration were selected for the study. Patients whose conditions required the use of antibiotics were not included in the study. Of 63 patients, 29 had cholera, 15 rotavirus infection, 13 ETEC, and 6 had Shigella (see table 1).

This study is more completely reported in L C Chen and N.S Scrimshaw (eds), Diarrhea and Malnutrition: Interactions, Mechanisms. and Interventions New York (Plenum, 1982)

TABLE 1. Clinical Summary of Study Patients (Mean + SEM)

a Cholera patients were oIder. purged more, and were more malnourished; patients in the other groups were comparable for age, body weight. dehydration
status and purging rates
b. Figures in brackets indicate number of patients

TABLE 2. Mean Intake of Calories During the Acute Stage ^a, and 2 Weeks (R1) and 8 Weeks (R2) after Recovery (All calorie values were obtained by subtracting 10 per cent of the actual calorie intake to correct it to metabolizable energy)

a Figures in brackets indicate number of patients

Approval of the Study

Prior permission of the Human Rights Ethical Review Committee and the Research Review Committee was obtained for the study. Informed consent of the parents or guardians of the children was also obtained before the study.

Environment

The study was conducted in an air-conditioned metabolic study unit of ICDDR, B. Dacca Hospital. Patients were always accompanied by an attendant (usually mother or grandmother) and kept under 24hour surveillance by trained nurses. Stools and urine were collected separately using uribags.

Study Diet

The purpose was to keep the food as close to what the children usually ate, because in a pre-trial experiment when homogenized food was offered to a group of hospitalized children, food intake was very low. When familiar foods were offered, intake of food improved. Strict intake and output charts were maintained for each study patient.

Duration of the Study

The study was conducted for 72 hours during the acute stage of diarrhoea and two and eight weeks after recovery. Usually, diarrhoea stopped three to five days after admission and patients were discharged from the hospital after seven to ten days.

Results

On average, food intake was reduced by 30 per cent in all patients with diarrhoea of any aetiology (table 2).

No apparent deleterious effects occurred from food intake in terms of stool volume or duration of diarrhoea.

Absorption of nitrogen, fat, and calories was most affected in acute rotavirus diarrhoea, and nitrogen absorption remained impaired even eight weeks after recovery (table 3).

ETEC patients showed better absorption of all nutrients in the acute stage, compared with that in patients with diarrhoea of other aetiologies, but did not show any improvement two weeks after recovery. Comparable improvement was noticed at eight weeks.

TABLE 3. Mean Intake of Nitrogen during the Acute State ^a, and 2 Weeks (R1) and 8 Weeks (R2) after Recovery

a. Figures in brackets indicate number of patients.

In Shigella, absorption of nitrogen was comparatively less than for other nutrients during the acute stage.

Cholera patients showed steady improvement in absorption of all nutrients after two weeks of convalescence.

Absorption of carbohydrate was least affected in patients with diarrhoea of any aetiology during the acute stage and two and eight weeks after recovery.

31. The effect of dietary fibre on digestibility of nutrients in a typical chilean diet

J. Espinoza, O. Brunser, M. Araya, J.I. Egana, 1. Pacheco, and S. Krause

Institute of Nutrition and Food Technology (INTA). Universidad de Chile. Santiago, Chile

Objectives

1. To evaluate the effect of fibre quantity on nutrient absorption and digestibility.

2. To define the influence of types and amounts of fibre on nutrient digestibility.

3. To assist in the formulation of food supplementation programmes in food and nutrition planning, taking into account the results of this research.

Experimental Design

Environment

The Metabolic Ward where all studies were performed. Ambient temperatures ranged from 8 to 20°C.

Subjects

Eight males, volunteers, belonging to the lowest socio-economic level of the Chilean population, 18 to 31 years old, were admitted to the Metabolic Ward. Subjects were selected from individuals living in a periurban slum in Santiago, Chile, and were given: (a) questionnaires to confirm their low socio-economic level and to disclose the presence of intercurrent diseases; (b) a physical examination and anthropometric evaluation (including skinfold measurements); and (c) two intestinal absorption tests (Dxylose, serum carotene).

Diets

The design included two test periods. During these periods diets provided 0.8 9 of egg protein/kg/day; 104 9 lipid/day, and calories enough to satisfy protein nutritional needs and to avoid fluctuations in body weight. A vitamin-mineral supplement to meet NAS-NRC daily recommended allowances was given. Either 6.8 9 or 20.5 9 of fibre/day were added to diets during the first and second period, respectively. These levels of fibre were established using data from previous food survey studies performed at INTA. Structured fibre was incorporated as both vegetables (lettuces, onions and carrots) and fruits (pears and apples). Animal protein was 89.3 and 76 6 per cent of total ingested protein for the first and second period, respectively

Duration

Each balance period lasted 12 days; the first three days served for adaptation to the diet and the following days for collection of specimens. Between both periods of study, subjects stayed at home for three days where they ate their usual diet.

Measurements Taken

Body weight was measured each day. Anthropometric measurements were obtained at the beginning and at the end of each study period. Faecal samples were pooled for eight-day periods. The beginning and end of the collection periods were marked with the aid of carmine red marker. and nitrogen, fat. and fibre were measured in aliquots.

The following parameters were determined daily: number of stools, average wet and dry weights. Daily urine collections were made to measure output, nitrogen, urea, and creatinine.

Nitrogen and fibre content were quantified in the food ingested. Fibre was analysed for cellulose, hemicellulose, lignin, and minerals in the food ingested as well as in the stools.

Nitrogen balance studies were calculated for the last five days of each study period.

The differences observed are compared by Student's t-test for paired samples.

Results

Socio-economic evaluation of subjects revealed that the individuals belonged to the low stratum (table 1).

TABLE 1. Evaluation of the Socio-economic Status of the Individuals Selected for the Study, According to the Modified Graffar Test

a. 5-14 points = misery, 15 24 points = middle-low, 25 35 points = high-low

TABLE 2. Anthropometric Evaluation Expressed as a Percentage of the Standard, at the Beginning and the End of the Investigation

TABLE 3. Examination of Stools for Presence of Cysts, Ova, Parasites and D-Xylose Blood Test

a. CEH = Entamoeba hystolitica cysts b. CGL = Giardia lamblia cysts

Table 4. Daily Nutrients Ingestion

TABLE 5. Quality of the Fibre Ingested During the First and Second Period of Study (g/day)

TABLE 6. Stool Weight: Total Dry and Wet (g/day)

Stool total weight: 1st vs. 2nd period: P < 0.0001
Stool dry weight: 1st vs. 2nd period: P < 0.025
Stool wet weight: 1st vs. 2nd period: P < 0.0005
a Figures in brackets denote percentages

TABLE 7 Faecal Nitrogen Excretion (g/day) (P < 0 005)

Subject	First Period	Second Period
L. H.	2.08	2.75
S.T.	1.47	1.91
J.R.	0.73	1.00
R.E.	1.93	2.26
R.L.	1.28	2.07
S.L.	0.99	2.36
E.F.	0.61	1.85
J.B.	0.86	1.89
± SD	1.24 ± 0.55	2.01 ± 0.51

TABLE 8. Faecal Fat Excretion (g/day) (P < 0.001)

Subject	First Period	Second Period
L.H.	2.54	5.33
S.T.	2.72	4.31
J.R.	1.89	2.79
R.E.	1.98	3.30
R.L.	2.10	2.61
S.L.	1.96	4.71
E.F.	1.97	3.01
J.B.	2.06	3.38
± SD	2.15 ± 0.31	3.68 ± 0.99

Anthropometric evaluation is shown in table 2. Variations during the study were less than 5 per cent. Arm perimeter and arm-muscle circumference, as well as arm-muscle area, were below international normal standards (Jelliffe, D., 1966, and Frisancho, A.R., 1974), which is usual in these types of populations according to our previous experience.

Stool cultures were negative in almost all subjects, as shown in table 3. The physical examination and biochemical studies were within normal limits. The D-xylose absorption test was below 20 mg per cent in six subjects (table 3).

Protein, nitrogen, lipids, carbohydrate, and caloric intake (table 4) were similar in both periods of study.

Fibre was offered as fresh vegetables and fruits. The amounts and quality of the fibre are shown in table 5. Cellulose was the main component, and cell walls consisted of hemicellulose, cellulose, Iignin, and ash. As expected, during the second testing period, these constituents were increased three-fold.

During the second period, dry- and wet-stool weight increased significantly compared with that in the first period (table 6).

Faecal nitrogen, fat, and fibre content significantly increased during the high-fibre ingestion period (tables 7, 8 and 9).

Nitrogen and fat digestibility were decreased during the higher-fibre intake period. Fat was less affected than nitrogen (tables 10 and 11).

Fibre digestibility increased significantly during the second period compared to the first one. Cell wall, hemicellulose, lignin, and cellulose digestibility increased 18.4, 13.1, 30.3 and 17.4 per cent, respectively (table 12).

TABLE 9. Faecal Fibre Excretion (g/day)

Subject	First Period					Second Period
	Cell Wall	Hemicellulose	Lignin	Cellulose	Ash	Cell Wall	Hemicellulose	Lignin	Cellulose	Ash
L.H.	5.05	1.24	0.92	2.79	0.10	10.53	2.73	1.69	5.87	0.24
S.T.	4.54	0.92	1.12	2.45	0.05	8.25	2.54	1.76	3.86	0.09
J.R.	4.38	1.17	1.21	1.96	0.04	8.21	2.31	2.11	3.72	0.07
R.E.	4.10	1.10	0.96	2.00	0.04	7.57	2.39	1.62	3.48	0.08
R.L.	3.65	1.17	0.86	1.57	0.05	6.99	2.18	1.88	2.85	0.08
S.L.	4.44	0.92	0.88	2.60	0.04	11.50	3.04	1.99	6.26	0.21
E.F.	4.25	0.89	1.21	2.11	0.04	9.33	1.93	2.01	5.24	0.15
J.B.	3.78	0.85	0.87	2.03	0.03	9.96	2.56	1.89	5.42	0.09
±	4.27	1.03	1.00	2.19	0.05	9.04	2.46	1.87	4.59	0.13
SD	± 0.44	± 0.15	± 0.15	± 0.40	± 0.02	± 1.55	± 0.34	± 0.17	± 1.26	± 0.07

TABLE 10. Nitrogen Digestibility (Percentage) (P < 0.005)

Subject	First Period	Second Period
L.H.	71.44	62.43
S.T.	77.85	70.85
J.R.	89.67	86.08
R.E.	72.52	67.96
R.L.	82.99	72.36
S.L.	85.79	66.35
E.F.	90.38	71.55
J.B.	90.34	77.99
± SD	82.62 ± 7.83	71.95 ± 7.32

TABLE 11. Fat Digestibility (Percentage) (P < 0.005)

Subject	First Period	Second Period
L.H.	97.50	95.05
S.T.	97.14	95.63
J.R.	98.11	97.38
R.E.	98.09	96.96
R.L.	97.92	97.50
S.L.	98.08	95.53
E.F.	98.12	97.33
J.B.	97.97	96.97
± SD	97.87 ± 0.36	96.54 ± 0.98

Urine creatinine, urea, and total nitrogen decreased during the higher fibre-ingestion period, but only the latter was significantly different (table 13).

Nitrogen balance was positive throughout the study in all except two subjects during the second period (see balance study sheet).

Conclusions

This investigation was performed on individuals belonging to a low socio-economic level and living in a periurban slum. Previous studies carried out by us showed that individuals living in similar conditions present a mild degree of intestinal malabsorption with non-specific changes in the small-intestinal mucosa. These studies confirm the presence of an environmentally induced, chronic enteropathy.

TABLE 12. Digestibility of Fibre Constituents (Percentage)

Subject	First Period					Second Period
	Cell Wall	Hemicellulose	Lignin	Cellulose	Ash	Cell Wall	Hemicellulose	Lignin	Cellulose	Ash
L.H.	26.06	23.93	25.81	26.81	28.57	48.61	44.29	54.20	49.00	38.46
S.T.	33.53	43.56	9.68	35.86	64.29	59.74	48.16	52.30	66.46	76.92
J.R.	35.87	28.22	2.42	48.69	71.43	59.93	52.86	42.82	67.68	82.05
R.E.	39.97	32.52	22.58	47.64	71.43	63.06	51.22	56.10	69.77	79.49
R.L.	46.56	28.22	30.65	58.90	64.29	65.89	55.51	49.05	75.24	79.49
S.L.	34.99	43.56	29.03	31.94	71.43	43.88	37.96	46.07	45.61	46.15
E.F.	37.77	45.40	2.42	44.76	71.43	54.47	60.61	45.53	54.47	61.54
J.B.	44.66	47.85	29.84	46.86	78.57	51.39	47.75	48.78	52.91	76.92
	37.43	36.66	19.05	42.70	65.18	55.87	49.80	49.36	60.14	67.63
SD	6.49	9.40	12.25	10.38	15.48	7.58	6.95	4.57	10.94	16.95

TABLE 13. Urine Volume and Creatinine, Urea Nitrogen, Urea and Total Nitrogen Excretion During the First and Second Testing Periods

Subject	First Period					Second Period
	Volume (ml/24 hrs)	Creatinine (mg/24 hrs)	Ureic Nitrogen (g /24 hrs)	Urea (g/24 hrs)	Total Nitrogen (g/24 hrs)	Volume (ml/24 hrs)	Creatinine (g/24 hrs)	Ureic Nitrogen (g/24 hrs)	Urea (g/24 hrs)	Total Nitrogen (g/24 hrs)
L.H.	2,394.00	985.90	2.63	5.63	4.15	2,692.00	1,107.40	2.78	5.95	3.57
S.T.	2,104.00	1,104.78	2.48	5.30	3.99	1,894.00	1,033.36	2.16	4.61	3.59
J.R.	3,028.00	1,214.78	3.71	7.94	5.58	3,146.00	1,054.42	4.06	8.69	5.58
R.E.	1,402.00	1,186.28	2.72	5.81	4.23	2,366.00	1,276.90	3.14	6 72	4.07
R.L.	1,884.00	1,485.32	3.76	8.05	5.36	1,820.00	1,398.34	3.34	7.15	4.79
S.L.	2,146.00	1,133.00	4.02	8.60	5.48	2,524.00	1,281.78	2.92	6.26	3.73
E.F.	2,184.00	1,072.36	4.13	8.83	5.49	2,786.00	1,142.46	3.58	7.66	4.10
J.B.	2,326.00	1,175.04	5.80	12.40	7.46	2,748.00	1,202.76	4.98	10.65	6.16
	2,171.00	1,169.68	3.66	7.82	5.22	2,497.00	1,187.18	3.37	7.21	4.45
SD	457.67	146.76	1.09	2.33	1.13	454.43	126.20	0.86	1.84	0.97
First vs. second period:					(P < 0.05)	(NS)	(NS)	(NS)	(P < 0.01)

High-fibte intake in this group of volunteers included:

1. Increased faecal excretion of nitrogen and fat. The effect was more intense than in similar studies performed in young individuals living in a sanitary environment.

2. Increased faecal excretion of fibre. This correlates better with the wet weight of stools, suggesting a water-trapping effect of the fibre.

3. Decreased digestibility of fat and nitrogen.

4. Increased fibre digestibility. All fibre fractions were affected, but lignin showed the most important change.

5. The increase in faecal weight during high-fibre consumption was associated with a reduction in total nitrogen excreted in urine. Nitrogen balance was not affected by fibre intake.

Individuals who receive borderline-quality diets with high fibre content have increased losses of nutrients. This may derange their nutritional status and should be considered in daily dietary allowance recommendations.

32. Protein digestibility of common beans: the role of polyphenolic compounds

R. Bressani, D.A. Navarrete, E. Hernández. and L.G. Elías

Division of Food and Agricultural Chemistry, Institute of Nutrition of Central America and Panama (INCAP). Guatemala City, Guatemala

It is well recognized, from data obtained in experimental animals and humans, that bean protein digestibility is relatively low compared with that in other vegetable protein sources. Various factors have been proposed as responsible; however, very little evidence has been developed to demonstrate their specific role. Beans have been shown to contain polyphenolic compounds, which could partially contribute to their low protein digestibility.

Objectives

1. To determine the protein digestibility of common beans (Phaseolus vulgaris).

2. To establish the possible role of polyphenolic compounds in bean-protein digestibility.

Experimental Design

Subjects

A total of 12 healthy, young adult male subjects described in table 1 were used in each of six digestibility asays. The same subjects were used in all trials.

Environment

The subjects lived in their homes in Guatemala City and worked at INCAP. All their meals were eaten in the Metabolic Unit of the Division of Food and Agricultural Chemistry. The daily ambient temperature ranged from 21° to 25°C. Relative humidity ranged from 72 to 85 per cent. Guatemala City is 1,510 metres above sea-level.

TABLE 1. Physical Characteristics of Experimental Subjects

TABLE 2 Basal Low Nitrogen Containing Diet

a. Made from wheat starch
b. Made from corn starch, margarine and herbs
c. UNICAP-T

TABLE 3. Calories, Protein, and Polyphenolic Compounds in Dried Cooked Samples

Physical Activity

All men performed their usual chores.

Experimental Diets

Basal diet: This diet is described in table 2. It contained 2,400 kcal and provided about 25 mg N/kg/day.

Common bean samples: Four bean cultivars of different seed-coat colour were chosen: one red, one white, and two black. An additional sample was included consisting of an equal weight mixture of black and white. Protein from white cheese made from skim milk was used as a reference. The bean samples were cooked with water in a ratio of one part beans to three parts water at 15 pounds per square inch (psi) for 30 minutes. They were then put with the cooking liquid into a forced-draught oven at 60°C until dry. The samples were ground, analysed as shown in table 3, and stored at 4°C until used. The amount of bean powder for each experimental subject was weighed daily, hydrated with hot water to a paste, and consumed as such. The total amount per individual per day was fed in three equal portions at 8 a.m., 12 noon, and 5.30 p.m.

Experimental Details

Two studies with the same individual were performed. In each, a modified Latin square design was used. in both studies. four continued experimental periods were conducted. During the first three the protein sources were randomly assigned. During the last period the low-protein diet was fed. In Study 1, cheese and red and black beans (J) were assayed. In Study 2, the samples were the black bean (1), the white bean, and the black-and-white-bean mixture. Each study lasted six days. of which three were used for adaptation and three for collection of urine and faeces. Faecal markers were given with the last meal of the adaptation period and with the last meal of the experimental period. Collections of faeces and urine were made daily. Protein intake was adjusted at 0.6 g/kg/day with calories at 45 kcal/kg/day.

TABLE 4. Apparent Protein Digestibility of Beans and Cheese

Subject	Red Beans (R)	Black Beans (Jalpatagua)	White Beans (W)	White/Black Beans 50:50 (W:B)	Black Beans (Ipala) (BI)	Cheese (C)
C.E.	83.4	55.2	66.6	60.1	47.8	82.2
F.M.	53.2	47.3	52.9	50.8	55.9	77.8
A.O.	45.9	50.4	47.6	55.3	44.5	72.2
V.R.	74.9	46.6	82.6	82.9	64.5	77.6
A.G.	51.5	39.9	59.0	46.3	54.6	72.2
M.R.	42.7	40.6	50.1	49.9	42.7	67.6
O.B.	39.2	71.3	57.8	57.9	48.0	73.2
R.S.	58.6	64.5	58.7	54.6	61.7	75.2
M.M.	46.6	45.4	61.7	53.0	48.3	69.1
S.E.	82.0	44.5	76.0	58.9	55.6	78.9
J.P	35.3	35.7	64.9	61.4	54.1	77.4
R.C.	55.4	55.9	67.5	58.4	62.7	84.1
±S error	55.7±4.60	49.6±2.95	62.1±2.92	57.4±2.65	53.4±2.08	76.2±1.40
Standard deviation	16.2	10.2	10.1	9.1	7.2	4.9
Coefficient of var. %	29.1	20.6	16.3	16.0	13.5	6.5
1. F = 9.45%

TABLE 5. Regression Equations between Absolute Intakes of Tannic Acid (TA) and of Catechin (C) and Faecal Nitrogen (FN) and Protein Digestibility (PD) in Adult Humans

a. P < 001
b. P < 0.05

Summary of Main Results

The individual apparent protein digestibility of the bean cultivars and of the reference protein is shown in table 4. Variability among individuals for bean samples was high for red beans, intermediate for black and white, and more uniform for cheese. All bean samples gave a significantly lower protein digestibility than cheese; however, white beans showed the highest value among bean samples and black beans the lowest.

Absolute intakes of tannic acid or of catechin were positively correlated (P > 1 %) with faecal nitrogen excretion. Conversely. polyphenolic compounds expressed as tannic acid or as catechin equivalents were negatively correlated with protein digestibility. as shown in table 5.

Conclusions and Comments

From the results presented it is evident that polyphenolic compounds are contributing factors in decreasing the protein digestibility of beans. Their elimination from beans would probably cause an increase in average apparent digestibility from a value of 56 per cent to around 64 per cent. However, it must be noted that in the present study, varietal differences among beans, independent of polyphenolic compounds, may have obscured the specific effect of polyphenolic compounds - an aspect that must be clarified. Furthermore, catechin, the monomeric unit of many condensed tannins, is more effective in decreasing digestibility than tannic acid, although there is a highly significant correlation (r = +0.89) between tannic acid and catechin equivalent. This suggests the need for a better identification of polyphenolic compounds in beans. From the data it appears that 1 mg per cent of catechin in bean dry matter decreased nitrogen absorption by 0.23 mg/kg/day. Of importance also is the role of polyphenolic compounds in relation to the forms of bean consumption and their impact when consumed in mixed diets.

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