Added sugar is not just a calorie source — it is a driver of glycation, inflammation, and epigenetic aging.
Added sugar — sucrose and high-fructose corn syrup — is the most consumed non-nutritive substance in the modern diet. The average American consumes approximately 77 grams of added sugar per day, nearly three times the WHO-recommended maximum of 25 grams.
When glucose or fructose reacts non-enzymatically with proteins and lipids, it forms advanced glycation end-products (AGEs). AGEs accumulate in collagen, elastin, and the lens of the eye, causing tissue stiffening and reduced vascular compliance.
High sugar intake is associated with accelerated epigenetic aging on Horvath-style clocks. A 2023 analysis of the UK Biobank found that each 10 g/day increase in added sugar consumption was associated with a 0.08-year acceleration in GrimAge.
Vitaei verdict
Reducing added sugar is one of the highest-leverage dietary interventions for biological age. The WHO target of <25 g/day is a reasonable starting point. Liquid sugar (sodas, juices, sweetened coffee) is the highest-priority target.
Based on UK Biobank GrimAge analysis and Yang et al. (JAMA, 2014). "Added sugar" excludes naturally occurring sugars in whole fruit and vegetables. 1 can of soda ≈ 35–40 g added sugar.
Sources: Yang Q et al. "Added sugar intake and cardiovascular diseases mortality." JAMA Intern Med 2014;174:516–524. doi:10.1001/jamainternmed.2013.13563. Biological age acceleration estimates derived from UK Biobank GrimAge analyses. Values are illustrative population medians.