To assess nutritional status using red-cell folate (RCF) and associated health behaviours including fruit and vegetable intake, smoking, drinking and physical activity in two Indigenous populations living in remote northern Australia.

A cross-sectional survey conducted during 1998–2000.

Twenty-six rural communities in north Queensland, Australia.

A total of 2524 Indigenous people aged 15 years and over was included in the study. Self-reported fruit and vegetable intake, tobacco smoking, alcohol intake and physical activity were recorded. RCF was measured using the Bayer Advia Centaur automated immunoassay system. The association between low RCF (RCF<295 nmol/l) and risk factors was analysed using general linear models adjusted for demographic factors and covariates, namely BMI, diabetes and dyslipidaemia.

The prevalence of RCF deficiency was higher in Aboriginal participants compared with Torres Strait Islanders (25·6 % v. 14·8 %, P < 0·001). Young women of childbearing age were more likely to have low RCF. Among Aboriginal adults, smoking was strongly associated with low RCF (risk ratio = 1·9, 95 % CI 1·5, 2·5 in females and risk ratio = 2·9, 95 % CI 1·9, 4·2 in males).

Indigenous Australians, especially women of childbearing age, had high prevalence of low RCF. Smoking was associated with insufficient folate independent of fruit and vegetable intake and alcohol consumption in the Aboriginal population. This population with an already higher risk of obesity and higher rate of tobacco smoking should be targeted to improve nutrition status to prevent ill health such as diabetes and CVD.