The association between diet quality and subclinical inflammation among children aged 6-18 years in the Eastern Cape, South Africa

Objective: The study aimed to investigate, for the first time, the association between diet quality (food variety and dietary diversity), intakes of anti-inflammatory nutrients and food groups, and subclinical inflammation as assessed by categories of high-sensitivity C-reactive protein (hs-CRP). Design: Cross-sectional study. Setting: Resource-poor, rural children in the Eastern Cape, South Africa. Subjects: A sample size formula determined a representative sample of 235. Five schools were purposively selected and cluster sampling used to select 240 participants. Measurements included 24 h recall and dietary diversity questionnaires, anthropometric and biochemical measurements. Results: The sample consisted of 50·4 % (n 118) girls and 49·6 % (n 116) boys. No obesity was found, but overweight was prevalent in 4·2 % of the children. The hs-CRP concentration (median (25th, 75th percentile)) of the low, medium and high risk inflammatory categories was 0·6 (0·4, 0·7), 1·6 (1·2, 2·2) and 4·2 (3·4, 6·4) mg/l, respectively. Body composition parameters did not differ between hs-CRP groups. Most of the anti-inflammatory nutrient intakes (dietary Fe, Zn, Mg, vitamin C, folate, linolenic acid, linoleic acid, MUFA and PUFA) differed significantly between the hs-CRP groups, with intakes increasing from low to high hs-CRP groups, with similar results for linolenic acid (P=0·022) intake. No significant relationships between hs-CRP and any of the food groups could be established, but significant relationships were established between hs-CRP levels and the high density of living arrangements and unhygienic ablution facilities. Conclusions: Although no link could be established between overnutrition and hs-CRP levels, an association was found between hs-CRP and dietary quality, as well as socio-economic status.