A University of Minnesota-led study found a link between long-term consumption of artificial sweeteners and increased body fat, particularly around the abdomen. The research identified aspartame, saccharin, and diet beverages containing these sweeteners as associated with higher fat stores — a finding that challenges the common assumption that artificial sweeteners help with weight management.
A growing body of evidence
This study adds to earlier research on the metabolic effects of low-calorie sweeteners. Findings from 2017 showed that artificial sweeteners could disrupt normal metabolism and promote fat buildup in human fat cells. A 2021 study found that aspartame consumption over a seven-week period led to weight gain primarily through fat accumulation, with increases becoming noticeable starting in the third week.
The gut microbiome connection
Research from 2019 indicated that artificial sweetener intake may alter the gut microbiome, offering a possible biological mechanism behind the reported effects on weight. More recent research in mice found that popular sweeteners such as sucralose and stevia negatively affected the gut microbiome and gene expression related to metabolism, with potential consequences that might extend across generations — a finding that researchers say warrants further investigation in humans.
The zero-calorie paradox
Together, these studies point to a paradox: despite containing little to no calories, artificial sweeteners may still contribute to increased fat storage and metabolic changes that undermine weight-control efforts. The effect appears particularly pronounced in abdominal fat, which is linked to several downstream health risks including cardiovascular disease and type 2 diabetes.
What this means if you drink diet soda
Regulatory agencies currently consider approved sweeteners safe for consumption within established limits, and this research doesn’t change that official guidance. But the emerging evidence suggests it may be worth reviewing long-term metabolic effects more closely, especially for people who consume diet sodas or sugar-free products daily as a primary calorie-reduction strategy. For current safety guidance, see the FDA’s page on high-intensity sweeteners.
