Artificial Sweeteners Linked to Weight Gain and Type 2 Diabetes, Study Says

Artificial sweeteners may lead people to put on weight and put them at risk of type 2 diabetes, according to researchers.

The team arrived at their conclusion after reviewing existing evidence from the past decade on what are also known as non-nutritive sweeteners (NNSs).

Such products earn their name from the fact they don't contain any vitamins or minerals, meaning they have no nutritional benefit, and may contain zero or low levels of calories.

Over the past three decades, there has been a rise in the use of artificial sweeteners, according to the researchers. Between 2000 to 2012, the use among children rose by 200 percent, and 54 percent among adults, and with the market expected to grow to $2.2 billion by 2020.

The American Heart Association says NNSs are "one way to limit calories and achieve or maintain a healthy weight."

"When used to replace food and drinks with added sugars, it can help people with diabetes manage blood glucose levels. For example, swapping a full-calorie soda with diet soda is one way of not increasing blood glucose levels while satisfying a sweet tooth," the health organization states.

Lead author Professor Peter Clifton, an expert in obesity, nutrition, and diabetes at the University of South Australia, told Newsweek the team found a link between the sweeteners and weight gain and type 2 diabetes.

However, Clifton and colleagues concluded that more long-term studies on sweeteners are needed to "draw a firm conclusion" about their role in blood sugar control.

One paper his team used in their review involved 5,158 adults who were studied over the course of seven to eight years. Those researchers found people who consumed artificial sweeteners at least twice a day were more likely to gain weight than those who never did.

Clifton said the problem might be partly behavioral. Sweeteners can be a useful tool for weight loss if they are used correctly with a controlled diet. But he said people who use sweeteners often still eat sugar, and may feel permission to overindulge. He said sweeteners don't appear to make people crave sweet foods. "There are no simple solutions," he said.

Scientists also found studies involving animals indicating such products may change the gut microbiome, or the make-up of the bacteria.

In a statement, Clifton said: "Artificial sweeteners also change the gut bacteria which may lead to weight gain and risk of type 2 diabetes.

"A better option than low-calorie sweeteners is to stick to a healthy diet, which includes plenty of whole grains, dairy, seafood, legumes, vegetables and fruits and plain water."

Clifton told Newsweek the study was limited because it was based on observational studies, which can only show associations between factors, "so strong conclusions can't be made, Intervention studies are not numerous and are not at all conclusive."

"The associations with type 2 diabetes are really unexplained mechanistically," he said.

Edward Johnston, research communications officer at the charity Diabetes U.K. who did not work on the study, told Newsweek: "This review highlights that currently, there is not enough research to be able to draw conclusions on whether there is a link between artificial sweeteners and development of type 2 diabetes.

"What we do know is that artificial sweeteners are not a silver bullet, but they may be useful for some people looking to reduce their intake of sugary foods and drinks, lose weight or manage their diabetes. If you think you need more support on managing your diet, talk to your health care team for individual advice."

Erik Millstone, Professor Emeritus of the Science Policy Research Unit
at the University of Sussex who also did not work on the paper, told Newsweek the review was "exceptionally comprehensive."

"Very few of the studies that kept track of peoples consumption of artificial sweeteners and monitored their effects were sufficiently long-term, so more research would be helpful. But the available evidence is strong enough to justify imposing tighter restrictions on the use of artificial sweeteners," Millstone said.

"There is very little reliable evidence suggesting that artificial sweeteners help people to lose weight and to keep it off," he added. "The evidence suggesting that artificial sweeteners can make people feel hungry is limited, but quite robust."

Millstone advised: "Rather than encouraging people to shift from sugar sweetened products to artificially sweetened ones, people should be encouraged and indeed helped to get used to enjoying a less sweet diet."

This article has been updated with comment from Erik Millstone.

soda, cola, soft drink, stock, getty
A stock image shows a glass of soda. Diet drinks can contain artificial sweeteners. Getty

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