Detrimental Effects of Dietary Sugar on Human Health: A Decade of Evidence From 2015 Onward

Excessive dietary sugar intake has emerged as a major contributor to the global burden of non-communicable diseases over the past decade. While naturally occurring, sugars are present in whole foods, high consumption of added sugars, particularly from sugar-sweetened beverages and ultra-processed products, has been strongly associated with adverse metabolic and systemic effects. This review synthesizes evidence published between 2015 and 2025 on the detrimental impact of sugar on human health. Mechanistically, chronic high sugar intake promotes hyperglycemia, insulin resistance, hepatic de novo lipogenesis, uric acid production, oxidative stress, and formation of advanced glycation end products. These processes contribute to obesity, type 2 diabetes mellitus, non-alcoholic fatty liver disease, and cardiovascular disorders. Emerging data also suggest associations with cognitive impairment, renal dysfunction, gut microbiota dysbiosis, reproductive hormonal imbalance, and increased cancer risk, largely mediated through chronic inflammation and metabolic disruption. Although observational and interventional studies vary in design and quality, the overall body of evidence supports a consistent link between excessive added sugar consumption and multi-organ dysfunction. Public health strategies aimed at reducing added sugar intake may therefore play a critical role in preventing metabolic and chronic diseases. Continued research is needed to clarify dose–response relationships and long-term outcomes across diverse populations.