Background Frailty, a vulnerability to adverse health outcomes, and sarcopenia, a decline in muscle mass and strength or performance are associated with ageing. Frailty and sarcopenia predict increased mortality and hospitalisation, and sarcopenia often occurs with an increase in body fat known as sarcopenic obesity which elevates these risks further. Diet quality is well established as a predictor of mortality, but few studies have investigated diet quality in relation to frailty or sarcopenia, and findings are inconclusive. We have therefore examined the associations between diet quality, frailty and sarcopenic obesity categories.

Methods We used cross sectional data from community-dwelling men aged 71–91 years (British Regional Heart Study) in 2010–2012 recruited from 24 primary care practices. Men completed a food frequency questionnaire, from which the Healthy Dietary Index (HDI) and Elderly Dietary Index (EDI) were derived, and attended a physical examination. Frailty was based on the 5 components of the Fried frailty phenotype and we used a sarcopenic obesity classification which defines 4 groups; optimal, sarcopenic, obese or sarcopenic obese based on waist circumference and mid-arm muscle circumference. We used logistic regression models to investigate whether diet quality was associated with frailty and sarcopenia and/or obesity.

Results 1331/3137 men (42%) had data for sarcopenia/obesity, all covariates and diet quality and 1119 men (36%) for frailty, covariates and diet quality. After adjusting for age, social class, region of residence, smoking, alcohol consumption, cardiovascular disease and energy intake, men in the top quartile of the HDI score had a lower odds of being frail (0.58 95% CI 0.34, 0.96) compared with men in the bottom quartile, and men in the top quartile of either HDI or EDI had a lower odds of being obese compared with men in the bottom quartile (0.52 95% CI 0.33, 0.84% and 0.57 95% CI 0.38, 0.86 respectively). Neither the HDI or EDI was associated with sarcopenia or sarcopenic obesity, and the EDI was not associated with frailty.

Conclusion Higher diet quality based on both the HDI and EDI is associated with obesity but we found no evidence that diet quality is associated with sarcopenia in these elderly British men. However, our findings suggest that a higher diet quality as indicated by the HDI, a measure of adherence to WHO nutrient intake guidelines, might be relevant for the prevention or reversal of frailty.