Sugar substitutes, whether natural or artificial, are no alternative to reducing sugar intake in order to reduce weight or the risk of diet-related diseases, said the World Health Organization (WHO) in its latest guideline on sugar intake that was published last month.
Based on evidence from hundreds of randomized controlled trials,and observational studies the WHO concludes that sugar substitutes do not help in reducing weight or in reducing the risk of diet-related diseases. The global health organization notes that while non-sugar sweeteners may help some people lose weight over the short term, these changes are not sustained and do not confer any long-term benefit in reducing body fat in adults or children.
As such, in its guidance released on 15 May, 2023), the WHO does not recommend the use of sugar substitutes to help with either weight loss, or reduce the risk of diet-related diseases such as heart disease and diabetes. The WHO guidance is applicable to people all over the world, except those with preexisting diabetes.
Although the latest WHO guidelines exempt people with preexisting diabetes, this was not because sugar substitutes were a healthier option for such patients. It was only because the studies used in the WHO review did not specifically include people with diabetes, and as such a firm conclusion could not be drawn on the risks of alternative sugars on diabetic patients.
The review also suggests that there may be “potential undesirable effects” from long-term use of non-sugar sweeteners, “such as an increased risk of type 2 diabetes, cardiovascular diseases and mortality in adults.” Non-sugar sweeteners are widely used as an ingredient in beverages and prepackaged foods manufactured by the food industry.
Many people also consider these ‘artificial sweeteners’ to be a healthier option than refined sugars, and add them to their food and beverages. In its previous review on sugar intake in 2015, the global health body had recommended that adults and children reduce their daily intake of added sugars to less than 10 percent, which consequently led to greater interest in the use of non-sugar sweeteners.
The guidance is timely to many people who consume diet sodas and use sugar substitutes in the belief that it could help them reduce weight and maintain this healthful weight over time. More often than not, the chemicals used in non-sugar sweeteners have more side effects than benefits, including causing bloating and diarrhea in some people.
In addition, many sugar substitutes are hundreds of times sweeter than the normal white sugar used in homes. The continued use of these sugar substitutes for an extended period could cause other sweetened foods to taste less sweet, and lead to people craving more sweeter foods to attain the same satisfaction level.
The WHO review which examined more than 280 studies included both randomized controlled trials (RCT) and observational studies. In research, RCT is considered the gold standard as it balances participant characteristics, reducing bias and providing a rigorous tool to examine cause-effect relationships between an intervention and outcome. On the other hand, while observational studies can indicate an association with an outcome, they cannot show direct cause and effect.
Results from certain randomized trials showed that use of non-sugar sweeteners resulted in lower body weight and body-mass index (BMI), but most of these studies lasted three months or less. Longer-term studies did not show a sustained effect on body weight. In addition, in randomized trials that compared people who used non-sugar sweeteners to those who consumed nothing, an inactive placebo or water, there was no effect on body weight or BMI.
Moreover, observational studies found that higher intake of non-sugar sweeteners was linked to higher BMI and an increased risk of obesity. These studies also showed an increased risk of type 2 diabetes, cardiovascular disease, and death from cardiovascular disease or any cause. There was also an increased risk of bladder cancer, particularly among people who used saccharin.
The WHO recommendation applies to artificial and naturally-occurring non-sugar sweeteners, such as acesulfame K, aspartame, advantame, cyclamates, neotame, saccharin, sucralose, stevia and stevia derivatives. The inclusion of stevia, considered a natural sugar alternative, was a surprise to many, but experts point out ‘Natural does not necessarily mean healthier’.
Also, since low-calorie sugars and sugar alcohols, such as erythritol, are sugars themselves or derived from them, they were not considered as non-sugar sweeteners. As such, the new guidance did not review research related to them.
However, a recent study associated erythritol — used to add bulk to or sweeten stevia, monk fruit and other keto-friendly reduced-sugar products — with a higher risk of heart attack, stroke and early death.
Health experts, nutritionists and dietitians have voiced serious concern following publication of the latest WHO guidelines, as non-sugar sweeteners are often marketed to people with type 2 diabetes, obesity and existing cardiovascular disease — all of whom are at higher risk of future heart attack and stroke.
They also point out that sweetened beverages and many processed foods like cookies, cakes, pastries and breakfast cereals also tend to be high in added sugars or non-sugar sweeteners. These sweeteners also show up in pre-packaged sauces, dressings and condiments. Consumers need to check the ingredient list on packaged foods and beverages.
Shoppers should be on the watch for non-sugar sweeteners in the ingredient list, including items such as aspartame, sucralose or stevia, as well as added sugars such as high fructose corn syrup and cane sugar. Ideally, whenever possible, opt for whole, minimally processed foods, or cook your meals at home, as this gives you better control over the ingredients.
Experts add that while reducing added sugars and non-sugar sweeteners is advisable, equal attention should be given to promoting a diet that prioritizes whole, unprocessed foods such as fruits, vegetables, lean proteins and whole grains. They also stressed the importance of conducting additional research to better understand the long-term effects of non-sugar sweeteners, including in people with certain diseases such as inflammatory bowel disease, high cardiovascular risk and type 2 diabetes.
