Artificial sweeteners are linked to weight gain, not weight loss.

Artificial sweeteners might seem like a low- or no-calorie way to enjoy sweet food and not gain weight. But a new study links them to the opposite.

In the report, published in the Canadian Medical Association Journal, researchers analysed 37 studies on artificial sweeteners to see if they were successful for weight management.

The studies followed more than 400,000 people for about 10 years. Seven of the studies were randomised controlled trials, a type considered to be the gold standard in scientific research.
Artificial sweeteners did not appear to help people lose weight. Instead, observational studies that looked at consumption over time suggested that people who regularly consumed them—by drinking one or more artificially-sweetened beverages a day—had a higher risk for health issues like weight gain, obesity, diabetes and heart disease.
Study author Meghan Azad, an assistant Professor in the Department of Pediatrics and Child Health at the University of Manitoba in Canada stated : “I think there is an assumption that when there are zero calories, there is zero harm. This research has made me appreciate that there’s more to it than calories alone.”
Susan Swithers, a professor in the Department of Psychological Studies at Purdue University, said the new study adds to a growing body of research that suggests sugar substitutes are no magic bullet. She declared: “Unfortunately, the quality of evidence that would support using sweeteners is not really strong. I think we are at a place where we can say that they don’t help.”
It’s not yet clear whether artificial sweeteners actually cause harm, however. Observational studies that link the sweeteners to health problems do not prove the sweeteners themselves are responsible. Other factors may muddle the link; people who consume more artificially sweeteners may eat more processed food, for example, which is linked to a higher risk for obesity or heart-related problems.
Because artificial sweeteners have been associated with health problems, experts have several working theories to explain the link. Some researchers speculate that the sweeteners interfere with a person’s microbiome, a collection of gut bacteria crucial for the absorption of nutrients.
Regularly eating or drinking sugar substitutes may also cause people to crave sweeter foods more often. People may also believe that because they haven’t consumed calories, they have license to splurge elsewhere.
Some researchers also believe that sweeteners may interfere with the body’s mechanisms for metabolizing sugar. So far, research has not yielded definitive answers.