National Institutes of Health pediatric endocrinologist Dr. Kristina Rother, who wasn't involved in the study, said it is a strong piece of work that highlights the need for more and better-designed studies on low-calorie sweeteners.
At her lab, Azad is now studying what happens when people are given artificially sweetened beverages for several weeks.
Azad and her team noted the limitations of the research in their paper, saying numerous randomized controlled trials (a type of scientific experiment) they looked at were at high risk of bias. But for the most part they didn't follow members of the general population, instead following those who were already obese, and only for an average of about six months.
The team found the clinical trials did not show a clear benefit or a consistent effect on weight loss, despite often being promoted for this reason.
Artificial sweeteners have been scientifically linked to health issues including weight gain.
One potential positive effect of artificial sweeteners - not mentioned in the study - is that they reduce the chances of tooth decay. In the trials, half of the participants were asked to consume the alternative sweeteners and the other half were asked not to, and the scientists looked for differences between the groups. The researchers were most interested in how the nonnutritive sweeteners may be associated with people's body mass index, the worldwide measure to calculate body fat based on weight concerning height. Researchers wanted to look more broadly at what's going on by doing a large-scale analysis of dozens of studies on low-calorie sweeteners. People should avoid consuming the substances and opt for other methods to lose weight. After studying the randomized trials, which consisted of a total of 1,000 people, most of whom were trying to lose weight, the researchers found no evidence that artificial sweeteners led to weight loss. "This research has made me appreciate that there's more to it than calories alone". We do not conclude that it is not a true poison, except that it brings doubts, and it is necessary to find answers, " says Annie Ferland.
"Caution is warranted until the long-term health effects of artificial sweeteners are fully characterised", she said in a statement. "There is just not a lot of evidence out there for what the long-term impact might be". In the study, it was discovered that artificial sweeteners were being absorbed by the bacteria in the gut and changing the makeup of the essential bacterial cultures that live inside the digestive system. It could also alter the gut microbiome in a way that could interfere with metabolism.
"People who use artificial sweeteners or diet drinks think that they can eat cake".