Is obesity associated with iron status in the elderly? A case study from Sharpeville, South Africa

ObjectiveTo investigate the relationship between poor Fe status and overweight or obesity in elderly respondents in South Africa.DesignCross-sectional, observational baseline survey.SettingSharpeville, South Africa.SubjectsA sample size calculation determined a representative sample of 104 randomly selected elderly (≥60 years) respondents. Measurements included weight, height, biochemical and haematological parameters. Measured BMI was used to categorise the respondents into normal weight, overweight and obese groups.ResultsThe majority of the women were overweight (28·4 %) or obese (54·6 %); 58 % of the respondents had normal Fe status, 15 % were classified as Fe depleted, 9 % as Fe deficient and 13 % as Fe-deficient anaemic. Ten per cent of the respondents had low Hb levels with no other low Fe status parameters, and were thus anaemic due to other causes. A significant correlation (r = 0·318, P < 0·001) existed between BMI and high-sensitivity C-reactive protein (hs-CRP). hs-CRP was negatively correlated to serum Fe levels (r = −0·319, P < 0·001). No significant relationships existed between BMI and Fe status parameters.ConclusionsA coexistence of obesity and poor Fe status were observed in these elderly respondents. The positive relationship between hs-CRP and BMI indicated chronic inflammation in the higher BMI groups. The negative relationship between hs-CRP and serum Fe indicated that lower serum Fe levels were related to the inflammation linked with higher BMI. A relationship between obesity-related chronic, low-grade inflammation and poor Fe status has been found in adults, but the significance of the current study is that this relationship was also confirmed for elderly persons.