Micronutrient status of older coloured South Africans

Objective. To investigate the dietary intake and nutritional status of older coloured South Africans in the Cape Peninsula with regard to their micronutrient status. Design. Cross-sectional analytical study. Methods. A random sample of 200 non-institutionalised subjects in Cape Town aged ^ 65 years was drawn using a two-stage cluster design. Trained fieldworkers interviewed subjects to obtain demographic, dietary and lifestyle data, to draw fasting blood samples for biochemical, haematological, iron status and vitamin D (serum 25-hydroxyvitamin D (25(OH)D)), serum vitamin B12 and red blood cell folate analyses. Nutrient intake was assessed with a validated quantified food frequency questionnaire. Results. The micronutrient density of the diet of the majority of the subjects was inadequate, particularly in respect of calcium, zinc and vitamin D intakes. Seventeen per cent of the subjects had serum 25(OH)D levels in the deficient range for the elderly (< 10 ng/ml). Fourteen per cent of subjects were anaemic, classified on the basis of suboptimal haemoglobin concentrations; however, only one-third (31 %) of those with anaemia had haemopoietic nutrient deficiencies, associated with either iron (63%) folate (38%) or vitamin BI2 (25%) deficiency. A low prevalence of either folate or vitamin B12 deficiency was found. Raised serum ferritin concentrations (> 300 ug/l) were found in 6.4% of subjects and were probably caused by excessive alcohol consumption. Conclusions. The findings indicate a need for health promotion activities that will encourage an increased consumption of vegetables, fruit (especially those rich in vitamin C), wholegrain cereals, low-fat dairy products, fish, eggs, lean meat and liver in this age group to prevent the nutrient deficiency disorders identified in the present study.