The effects of vitamin C supplementation on the alterations in the circulating concentrations of cortisol, adrenaline, interleukin-10 (IL-10) and interleukin-1 receptor antagonist (IL-1Ra) which accompany ultramarathon running were measured using immuno-chemiluminescence, radioimmunoassay and ELISA procedures. Forty-five participants in the 1999 Comrades 90 km marathon were divided into equal groups (n = 15) receiving 500 mg/day Vit C (VC-500), 1500 mg/day Vit C (VC-1500) or placebo (P) for 7 days before the race, on the day of the race, and for 2 days following completion. Runners recorded dietary intake before, during and after the race and provided 35 ml blood samples 15 - 18 hrs before the race, immediately post-race, 24 hrs post race and 48 hrs post-race. Twenty-nine runners (VC-1500, n = 12; VC-500, n = 10; P, n = 7) complied with all study requirements. All post-race concentrations were adjusted for plasma volume changes. Analyses of dietary intakes and blood glucose and anti-oxidant status on the day preceding the race and the day of the race did not reveal that carbohydrate intake or plasma vitamins E and A were significant confounders in the study. Mean pre-race concentrations of serum vitamin C in VC-500 and VC-1500 groups (128 +/- 31 and 153 +/- 34 micromol/l) were significantly higher than in the P group (83 +/- 39 micromol/l). Immediate post-race serum cortisol was significantly lower in the VC-1500 group (p < 0.05) than in P and VC-500 groups. When the data from VC-500 and P groups was combined (n = 17), immediate post-race plasma adrenaline, IL-10 and IL-1Ra concentrations were also significantly lower (p < 0.05) in the VC-1500 group. The study demonstrates an attenuation, albeit transient, of both the adrenal stress hormone and anti-inflammatory polypeptide response to prolonged exercise in runners who supplemented with 1500 mg vitamin C per day when compared to < or = 500 mg per day.

Objective: To evaluate the long-term effect on micronutrient status of a b-carotene-, iron-and iodine-fortified biscuit given to primary school children as school feeding. Design: Children receiving the fortified biscuit were followed in a longitudinal study for 2.5 years n 108; in addition, cross-sectional data from three subsequent surveys conducted in the same school are reported. Setting: A rural community in KwaZulu-Natal, South Africa. Subjects: Children aged 6±11 years attending the primary school where the biscuit was distributed.Results: There was a significant improvement in serum retinol, serum ferritin, haemoglobin, transferrin saturation and urinary iodine during the first 12 months of the biscuit intervention. However, when the school reopened after the summer holidays, all variables, except urinary iodine, returned to pre-intervention levels. Serum retinol increased again during the next 9 months, but was significantly lower in a subsequent cross-sectional survey carried out directly after the summer holidays; this pattern was repeated in two further cross-sectional surveys. Haemoglobin gradually deteriorated at each subsequent assessment, as did serum ferritin (apart from a slight increase at the 42-month assessment at the end of the school year). Conclusions: This study has shown that fortification of a biscuit with b-carotene at a level of 50% of the Recommended Dietary Allowance (RDA) was enough to maintain serum retinol concentrations from day to day, but not enough to sustain levels during the long school holiday break. Other long-term solutions, such as local food production programmes combined with nutrition education, should also be examined. The choice of the iron compound used as fortificant in the biscuit needs further investigation.

A randomized controlled trial in KwaZulu-Natal (South Africa) of 428 primary-school pupils (stratified into 6 groups by age, sex and intervention) measured the effect of different anthelmintic treatments and iron supplementation regimens provided twice at 6-monthly intervals for 1 year (1996/97). Half the pupils received iron supplementation (ferrous fumarate 200 mg weekly for 10 weeks). Pupils received 2 anthelmintic regimens, either (i) albendazole 400 mg plus praziquantel 40 mg/kg or (ii) albendazole 400 mg on 3 consecutive days plus praziquantel 40 mg/kg or (iii) placebo. Baseline prevalences of Ascaris 55.9%, Trichuris 83.6%, hookworm spp. 59.4%, were reduced after 12 months for single-dose albendazole treatment to Ascaris 17.4% (P < 0.005), Trichuris 61.5% (NS), hookworm spp. 0% (P < 0.005), and for triple-dose albendazole treatment to Ascaris 14.8% (P < 0.005), Trichuris 25.0% (P < 0.01), hookworm 0% (P < 0.005). Schistosoma haematobium 43.4% was reduced among treated groups to 8.3% (P < 0.005). There were no significant changes in the anthropometry of the different treatment groups at either 6 or 12 months post treatment. Twelve months after treatment there was a significant increase in haemoglobin levels (P = 0.02) among pupils receiving triple-dose albendazole, praziquantel and ferrous fumarate; pupils receiving no anthelmintic treatment showed a significant decrease as did pupils who received triple-dose albendazole and praziquantel but no iron. Regular 6-monthly anthelmintic treatment significantly reduced the prevalence of Ascaris, hookworm spp. and S. haematobium infections (P < 0.05). Triple-dose treatment for Trichuris was significantly more effective than a single dose of albendazole 400 mg (P = 0.002). In areas with schistosomiasis, hookworm infection and high prevalence of Trichuris infection, combination treatment with praziquantel, triple-dose albendazole, plus iron supplementation, is likely to improve pupils' health and haemoglobin levels.

The objective of this study was to determine the nutritional status regarding vitamin A, iron and anthropometric indices and dietary intakes of children aged 2-5 years and their caregivers in a rural South African community. Micronutrient, haematological, anthropometric and dietary indicators were used to assess nutritional status during a cross-sectional survey. The setting was a low socioeconomic rural African community (Ndunakazi), approximately 60 km northwest of the coastal city of Durban in KwaZulu-Natal, South Africa. The subjects were children aged 2-5 years (n = 164), and their caregivers (n = 137). Of the preschool children, 50% had a low vitamin A status (serum retinol < 20 micrograms/dL), 54% were anaemic (Hb < 11 micrograms/dL), 33% had depleted iron stores (serum ferritin levels < 10 micrograms/L), and 21% were stunted (Z-score for height-for-age < -2SD). Of the caregivers, 30% had a low vitamin A status (serum retinol < 30 micrograms/dL), 44% were anaemic (Hb < 11 micrograms/dL), 19% had depleted iron stores (serum ferritin levels < 12 micrograms/L), and 40% and 26% were overweight (BMI > or = 24 and < 30) and obese (BMI > or = 30), respectively. The children and caregivers consumed a cereal-based diet, with phutu (a stiff porridge made with maize meal), rice and bread as staple foods. Quantitative dietary analysis showed that the dietary intakes were high in carbohydrates (approximately 70% of total energy), while fat intake was within the prudent dietary guideline of 30% of total energy intake. Median dietary intakes were below 50% of the RDA for calcium, zinc (children only), vitamin A, riboflavin, niacin (children only) and vitamin B12. These preschool children and their caregivers consumed a high carbohydrate diet deficient in most of the essential micronutrients. The poor quality of the diet was reflected in a poor vitamin A and iron status, and one-fifth of the children showed linear growth retardation. Nutrition education and intervention programmes should address micronutrient deficiencies, with the focus not only on quantity, but also quality of the diet.

No abstract