Artificial sweetener consumption is widely believed to be an effective method to limit caloric intake and maintain glycemic control. However, there is no evidence from long-term prospective analyses that the consumption of artificial sweeteners result in benefits in terms of weight loss and glycemic control (Swithers 2013). In fact, accumulating evidence now points to the opposite; that such products may precipitate metabolic derangements in susceptible individuals (Nettleton et al. 2016)."

Source : Artificially sweetened taste of insulin resistance? Editorial, journal of Applied Physiology, Nutrition and Metabolism, July 2016.

Several research projects have found that artificial sweeteners (especially Aspartame) can cause glucose intolerance - leading, in some cases, to type-2 diabetes. This is especially puzzling because users of the sweeteners tend to consume less natural sugars (sucrose + fructose). There is currently no known explanation for this effect.

In 2022, a large study conducted in France suggested that regular consumption of (some) artificial sweeteners can have a significant effect on the incidence of cardiovascular disease. The exact causes, however, have not yet been identified.

The findings from this large scale prospective cohort study suggest a potential direct association between higher artificial sweetener consumption (especially aspartame, acesulfame potassium, and sucralose) and increased cardiovascular disease risk. Artificial sweeteners are present in thousands of food and beverage brands worldwide, however they remain a controversial topic and are currently being re-evaluated by the European Food Safety Authority, the World Health Organization, and other health agencies.

Source : Artificial sweeteners and risk of cardiovascular diseases: results from the prospective NutriNet-Santé cohort BMJ 2022;378:e071204.

In 2022, the WHO released a systematic review and meta-analysis of the health effects of the use of non-sugar sweeteners. The 210-page technical review, though not easy to decipher, came to the broad conclusion that :

" […] there is no clear consensus on whether non-sugar sweeteners are effective for long-term weight loss or maintenance, or if they are linked to other long-term health effects at intakes within the ADI." ^{[ Adult Daily Intake ]} (ref.)

A study published in Arteriosclerosis, Thrombosis, and Vascular Biology found that Erythritol - a commonly used sugar substitute - may be linked to an increased risk of the formation of vessel-blocking blood clots.

Ingestion of a typical quantity of the non-nutritive sweetener erythritol, but not glucose, enhances platelet reactivity in healthy volunteers, raising concerns that erythritol consumption may enhance thrombosis potential." (ref.)