The consumption of diet drinks could leave people with increased food cravings, new research suggests, according to news outlet, NPR.
A study published recently in JAMA Network Open shows evidence that drinks made with sucralose may stimulate the appetite, at least among some people, and the research gives some clues as to why, NPR reported.
‟We found that females and people with obesity had greater brain reward activity” after consuming the artificial sweetener, said study author Katie Page, a physician specializing in obesity at the University of Southern California.
Both groups also had a reduction in the hormone that inhibits appetite, and they ate more food after they consumed drinks with sucralose, compared with after regular sugar-sweetened drinks. In contrast, the study found males and people of healthy weight did not have an increase in either brain reward activity or hunger response, suggesting they're not affected in the same way.
The study noted that earlier research focused on males and people of normal weight. But the new findings suggest that diet drinks sweetened with sucralose could be disadvantageous to the people who could benefit most from an effective diet strategy.
‟It is precisely people with obesity who disproportionately suffer from a strong drive to eat high-calorie foods,” said Laura Schmidt, a professor of health policy at the University of California, San Francisco, NPR reported her as saying.
Page and her team measured the response to diet soda in three ways. They used functional MRI brain images of 74 participants to document the activation of parts of the brain linked to appetite and cravings. They used blood samples to measure blood sugar and metabolic hormones that drive hunger, and they also tracked how much participants ate at a buffet table that was open at the end of each study session.
Some studies have shown benefits for dieters' efforts to lose weight, but long-term research has found that diet fizzy drinks consumption is linked to increased weight gain, according to NPR.
‟This study offers some clues as to why,” Schmidt told NPR. ‟Artificial sweeteners could be priming the brains of people with obesity to crave high-calorie foods.”
There's ongoing research into the complex ways that artificial sweeteners may influence metabolism and weight, said Susan Swithers, a behavioral scientist at Purdue University who was not involved in the new study but reviewed the findings.
‟These results are consistent with patterns that we've actually seen in my lab in [animal] studies,” she said.
One hypothesis is that it's not the artificial sweetener itself that has a direct effect on the body. The idea is that artificial sweeteners may confuse the body by tricking it into thinking sugar is coming.
‟You are supposed to get sugar after something tastes sweet. Your body has been conditioned to that,” Swithers explained. But diet soda may lead to problems because he sugar never arrives, and this may blunt the body's anticipatory responses and throw off the ability to efficiently metabolize sugar that's consumed later, NPR reported.
This could mean that ‟when you get the sweet taste without the sugar, that changes how you respond to sugar the next time, because you don't know whether it's coming or not,” Swithers said.
Swithers' lab documented that when animals with a history of consuming artificial sweeteners get real sugar, their blood sugar levels rise higher than those of animals not fed artificial sweeteners. ‟It's a small effect, but over time this could contribute to potentially significant consequences,” she explained.
If this is happening in some people who consume diet soda, it could add to the risk of Type 2 diabetes, because when blood sugar rises, the body has to release more insulin to absorb the sugar.
‟People with obesity might want to completely avoid diet sodas for a couple of weeks to see if this helps to reduce cravings for high-calorie foods,” Schmidt suggested to NPR.