Association of sugar intake with incident dementia in the UK Biobank: a prospective cohort study

Excessive sugar intake has been implicated in increased dementia risk; however, existing studies are constrained by small sample sizes and a primary focus on total sugar, with limited investigation into specific sugar subtypes. This study explores the relationship between sugar intake, its subtypes, and the incidence of dementia. We analyzed 172,516 participants from the UK Biobank who completed at least one 24-hour dietary recall (Oxford WebQ). Cox proportional hazards models estimated the hazard ratios (HRs) and 95 % confidence intervals (95 % CIs) for total sugar and its subtypes (free sugar, fructose, glucose, sucrose, maltose, lactose, and other sugars) about the risk of dementia. Sex-stratified analyses were also performed. Higher intakes of total sugar (HR = 1.292, 95 % CI = 1.148--1.453) and free sugar intake (HR = 1.254, 95 % CI = 1.117--1.408) were significantly associated with increased dementia risk. Positive associations were also observed for non-milk extrinsic sugars (HR = 1.321, 95 % CI = 1.175--1.486) and sucrose (HR = 1.291, 95 % CI = 1.147--1.452). These associations were evident in women, with higher intakes of total sugars, free sugars, glucose, sucrose, and non-milk extrinsic sugars independently linked to increased dementia risk, whereas no significant associations were found in men. Higher consumption of total sugars, free sugars, sucrose, and non-milk extrinsic sugars confers increased dementia risk, particularly among women.