Saccharin (Sweet'N Low)

Saccharin (Sweet'N Low) remains the most controversial artificial sweetener on this list due to its metabolic risks, not its outdated cancer link. A 2014 Nature study found that saccharin induces glucose intolerance by altering gut microbiota, a harm absent in sugar alcohols like sorbitol. This effect was observed at human-relevant doses, with changes occurring in just one week. Despite being removed from the US carcinogen list in 2000 after rat studies were deemed inapplicable, the compound triggers a 50% increase in blood sugar response in mice. Unlike #6 Sugar Alcohols (Maltitol), which ferment slowly, saccharin's impact on gut bacteria is rapid and reversible only after extended washout periods. Consumers seeking a low-calorie sweetener should weigh this metabolic disruption against the modest benefits of zero calories.