Drinking sugar-sweetened beverages may reduce stress while diet beverages sweetened with aspartame do not, according to a new study published in the Endocrine Society’s Journal of Clinical Endocrinology & Metabolism.
The study examined the effects of consuming sugar- and aspartame-sweetened beverages on a group of 19 women between the ages of 18 and 40. The researchers assigned eight women to consume aspartame-sweetened beverages, and 11 to drink sugar-sweetened beverages. For a 12-day period, the women drank one of the assigned beverages at breakfast, lunch and dinner. The participants were instructed not to consume other sugar-sweetened drinks, including fruit juice.
For three-and-a-half days prior to and after the study, participants consumed a standardized low-sugar diet and stayed at the University of California, Davis Clinical and Translational Science Center’s Clinical Research Center.
Before and after the 12-day experimental period, participants underwent functional MRI screenings after performing a psychological stress test to gauge the brain’s stress response. They also provided saliva samples to measure levels of cortisol – a hormone made by the adrenal glands that typically increases in response to stress.
Researchers found that women who drank sugar-sweetened beverages during the study had a diminished cortisol response to the stress test from their baseline, compared to women who were assigned to consume aspartame-sweetened beverages. Additionally, participants who consumed sugar-sweetened beverages exhibited more activity in the hippocampus under stress– a part of the brain that is involved in memory and is sensitive to stress – than those who drank aspartame-sweetened beverages. Activity in the hippocampus is thought to play a primary role in controlling the cortisol stress response.
“This is the first mechanistic evidence that high sugar – but not aspartame – consumption may relieve stress in humans,” said one of the study’s authors, Kevin D. Laugero, PhD, of the Western Human Nutrition Research Center of Agricultural Research Service and UC Davis. “The concern is psychological or emotional stress could trigger the habitual overconsumption of sugar and amplify sugar’s detrimental health effects, including obesity.”
“The results also suggest differences in dietary habits may explain why some people underreact to stressful situations and others overreact,” he said. Excessive reliance on sugar may abnormally blunt the ability to mount a stress response. Research has linked over- and under-reactivity in neural and endocrine stress systems to poor mental and physical health.
Image Credit: Wiki Commons