Introduction Diet is a key component of a healthy lifestyle for preventing type 2 diabetes. Despite a high prevalence of type 2 diabetes in Indians, the impact of diet has not been fully explored. This study aimed to investigate the association between fish intake and the risk of type 2 diabetes among adult men and women in India.

Methods Analysis is based on a population based cross sectional study of 99 574 women and 61 361 men aged 20–49 years included in India's third National Family Health Survey, 2005–2006. Effects of fish intake, determined by frequency of consumption (daily, weekly and occasionally/never), on the reported prevalence of diabetes were estimated using multivariate logistic regression after adjusting for frequency of consumption of milk/curd, eggs/chicken/meat, BMI status, tobacco smoking, watching television, age, education, living standard of the household, residence and geographic regions.

Results After adjustment for other dietary and lifestyle risk factors and socioeconomic and demographic characteristics, risk of diabetes was 1.3 times higher among both men (OR: 1.30; 95% CI 1.09 to 1.56; p=0.003) and women (OR: 1.27; 95% CI 1.06 to 1.52; p=0.009) who consume fish daily as compared to those who consume them occasionally or never. Weekly fish intake also contribute to a higher risk of diabetes both among men (OR: 1.52; 95% CI 1.20 to 1.93; p=0.001) and women (OR: 1.54; 95% CI 1.24 to 1.92; p<0.001) even after controlling for the effects of potentially confounding factors.

Conclusion Daily or weekly fish intake is associated with higher risk of diabetes among Indians, warranting further investigation. More epidemiological research with better measures of fish intake and clinical measures of diabetes is needed to validate the findings.