A question that comes up at every gathering: "is diet better, or the same?" In May 2023 the World Health Organization issued an official answer — but read it in full before deciding.
The recommendation
The WHO issued a guideline recommending against the use of non-sugar sweeteners for body weight control or to reduce the risk of non-communicable diseases[1],[2]. The systematic review underpinning it found their use confers no long-term benefit in reducing body fat in adults or children, and pointed to possible undesirable effects with long-term use, such as increased risk of type 2 diabetes, cardiovascular disease and mortality in adults[1].
Sweeteners covered: aspartame, sucralose, saccharin, acesulfame K, cyclamates, neotame, advantame, and stevia and its derivatives[1].
the evidence isn't decisive
body fat
(15 May)
Read the footnote: the recommendation is "conditional"
The WHO itself classified the recommendation as conditional, not strong[2],[3] — meaning the evidence is not decisive and policy decisions require local discussion. Scientific papers have even been published calling for the guideline to be reconsidered[4]. This isn't scepticism about the WHO, but honesty about the degree of certainty.
What this means for you practically
- Diet isn't a licence: a diet can with a large fast-food meal cancels nothing — and that is the core of the recommendation.
- If you're moving from regular to diet: a reasonable transitional step to cut sugar, but don't make it the final destination.
- The direction the WHO recommends: reducing sweetness overall — water, fruit with its natural sugars, and unsweetened drinks[1].