Sweet Stress Relief May Fuel Bad Habit

Chronic stress may spur overconsumption of sugar, possibly leading to obesity and other health problems

(RxWiki News) Downing a can of soda may provide some relief from a tension-filled day. But too much of a sweet thing can become an unhealthy habit.

A new study found that sugar-sweetened beverages may subdue the brain's stress responses. Diet drinks sweetened with aspartame, however, didn’t appear to have the same effect.

Kevin D. Laugero, PhD, of the University of California, Davis, and the Agricultural Research Service, led this study.

"This is the first evidence that high sugar — but not aspartame — consumption may relieve stress in humans," Dr. Laugero said in a press release. "The concern is psychological or emotional stress could trigger the habitual overconsumption of sugar and amplify sugar's detrimental health effects, including obesity."

Dr. Laugero and team looked at 19 women ranging in age from 18 to 40. Eight women were assigned to drink aspartame-sweetened beverages over a 12-day period. The other patients consumed sugar-sweetened drinks. They had one drink at breakfast, lunch and dinner each day of the trial.

At the start and end of the study, Dr. Laugero and team assessed the women’s brain stress responses using MRI (magnetic resonance imaging) and a math test. They also took saliva samples to determine levels of cortisol. Cortisol is a hormone made in the adrenal gland. It has been called the "stress hormone” because it is secreted at higher levels in response to stress.

Cortisol response to a math test declined for those drinking sugar-sweetened drinks compared to those in the aspartame group, Dr. Laugero and team found.

These researchers also assessed activity in the hippocampus. The hippocampus is part of the brain that is responsible for long-term memory. It is a target of stress hormones and usually becomes less active when the body is under stress. The hippocampus became more active in women who drank sugar-sweetened drinks compared to those in the aspartame group.

Dr. Laugero said that these results may help explain how sugar positively reinforces the temptation to eat comfort food when a person is stressed. This response to stress could lead to eating unhealthy amounts of sugar, which could in turn contribute to obesity. Obesity raises the risk of heart disease, stroke, high blood pressure and diabetes, according to the American Heart Association.

Just over a third of adults in the US are obese, according to the Endocrine Society, and sugary drinks have been identified as a factor in the problem. Half of the nation’s population drinks sugar-sweetened drinks on any given day, according to the Centers for Disease Control and Prevention.

"Although it may be tempting to suppress feelings of stress, a normal reaction to stress is important to good health,” Dr. Laugero said in a press release.

This study was published April 16 in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism. The University of California and the Agricultural Research Service funded this research. Dr. Laugero and team disclosed no conflicts of interest.

Review Date: 
April 16, 2015