"Glucocorticoids are produced when psychological or physical stressors activate a part of the brain called the 'stress axis,'" said Yvonne Ulrich-Lai, PhD, a postdoctoral fellow in the department of psychiatry. "These hormones help an individual survive and recover from stress, but have been linked to increased abdominal obesity and decreased immune function when produced in large amounts.
"Finding another way to affect the body's response to stress and limit glucocorticoid production could alleviate some of these dangerous health effects."
The laboratory findings were presented during a poster session Tuesday, Nov. 15, at the annual Society for Neuroscience meeting in Washington, D.C.
Dr. Ulrich-Lai and a team of researchers from the department of psychiatry showed that when laboratory rats chose to eat or drink sweet snacks their bodies produced lower levels of glucocorticoid.
She said that sweets--especially those made from sugar, not artificial sweetener--might do the trick.
"The sweets we are talking about are not the low-calorie, sugar-substitute variety," said Dr. Ulrich-Lai. "We actually found that sugar snacks, not artificially sweetened snacks, are better 'self-medications' for the two most common types of stress--psychological and physical."
Psychological stress could involve things such as public speaking, being threatened, or coping with the death of a loved one. Examples of physical stress are injury, illness, or prolonged exposure to cold.
During the study, researchers gave adult male rats free access to food and water and also offered them a small amount of sugar drink, artificially sweetened drink, or water twice a day. After two weeks, the rats were given a physical and psychological stress challenge. Following both types of stress, rats that had consumed the sugar drink had lower glucocorticoid levels than those that drank the water. Those drinking the artificially sweetened drink showed only slightly reduced glucocorticoid levels.
Dr. Ulrich-Lai noted that although her team was not studying the health effects of the sweetened drinks, they did not notice a body-weight increase in the rats consuming the sugar drinks.
James Herman, PhD, co-author, professor and stress neurobiologist in the department of psychiatry, said the next step will be to determine how these sweetened drinks are decreasing glucocorticoid production.
"We need to find out if there are certain parts of the brain that control the response to stress, then determine if the function of these brain regions are changed by sugar snacking," he said.
Co-authors also included Dennis Choi and Michelle Ostrander, PhD, both of UC's psychiatry department.