the nutritional status of - Health Systems Trust

3.3.10 IRON INTAKES
Tables 54 (a), (b) and (c) compare iron intakes with the USA RDA’s and the British LNRI and EAR. Because vulnerable
groups may suffer from parasitic infections (Schutte, 1995; Fincham, 1996a) which may increase iron requirements,
the higher RDA’s are used here to evaluate adequacy in Table 55.
From Table 55 it can be seen that the vulnerable groups with intakes less than 67 % (two thirds) of the RDA were
urban black infants, a small group of rural black children, girls aged 11 to 15.9 years, and adult women, aged 16 to
64.9 years. The low intakes of the girls and women are relative because their requirements are higher than those
of boys and men.
The low intake of iron is a serious, but complicated problem. An iron deficient state may be responsible for arrested
cognitive development of children. But in later life, it may possibly protect against coronary heart disease and iron
overload in genetically susceptible individuals (MacPhail & Bothwell, 1989). An iron fortification or supplementation
programme should therefore be targeted at young children and iron deficient women of childbearing age.
3.3.11 MAGNESIUM INTAKES
Magnesium intakes are related to the plant content (fruits, vegetables, legumes) of the diet. Table 56 (a) shows that
adult men and women, except for the group of rural black women, tended to have low magnesium intakes. The
data obtained by methods other than the 24-hour recall (tables 56 (b) and (c)), show adequate intakes, except for
coloured men and women. Therefore, there may be borderline magnesium deficiencies in some adult groups,
which could be rectified by inclusion of more fruit, vegetables and legumes in the diet.
3.3.12 POTASSIUM INTAKES
From Tables 57(a) and (b) it seems that in all groups for whom potassium intakes were calculated, the USA RDA’s for
potassium were met.
3.3.13 ZINC INTAKES
Zinc is a constituent of many enzymes in the body. It, therefore, plays an important role in metabolism. Unfortunately,
diagnosis of the consequences of low intakes, as well as zinc requirements, are not well understood. The richest
sources of zinc in the diet are lean meats and wholegrain cereal foods. Tables 58 (a) and (b) show that regardless
of which method was used, many groups had low intakes compared to the RDA’s. It seems that zinc may be one
of the micronutrients in the diet of South Africans that needs immediate attention.
3.3.14 PHOSPHORUS INTAKES
Tables 59 (a), (b) and (c) indicate that mean intakes of phosphorus in almost all groups were adequate, the exception
being black children when diets were assessed by the 24-hour recall method.
3.3.15 SODIUM INTAKES
All groups measured had higher mean intakes than the estimated safe and adequate daily dietary intakes of the
Food and Nutrition Board (1989), as can be seen in Tables 60 (a) and (b). High sodium intakes are associated with
hypertension which is one of the major chronic diseases of lifestyle in South Africa (Opie, 1995). A shift in the diet
to include more unprocessed foods and uncooked fruits and vegetables could reduce sodium consumption.
3.3.16 THIAMIN INTAKES
Mean intakes of thiamin (vitamin B1 or anti-beriberi factor) of all groups were adequate when compared to the RDA
(Tables 61 (a), (b) and (c)). From the available data it, therefore, seems that the mean intake of thiamin is not a
problem in the South African diet.
3.3.17 RIBOFLAVIN INTAKES
From Tables 62 (a), (b) and (c) it seems that coloured, Indian and rural black groups had inadequate riboflavin
(vitamin B2)) intakes. Dairy products are principle sources of riboflavin and increases in milk or sour milk consumption
could rectify this dietary deficiency.
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