Grabbing a sugary snack in times of stress may not be such a bad idea after all, research has suggested.
Experts are calling for research into effects in humans
A team from the University of Cincinnati found rats who consumed sweet things had lower levels of a stress-related hormone.
Glucocorticoid has been linked to obesity and a weakened immune system.
But the rat study, presented to the US Society of Neuroscience annual meeting, found the animals who opted for the sweeter option did put on weight.
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.
Rats that had consumed the sugar drink had lower glucocorticoid levels after both tests than those that drank the water.
Those drinking the artificially sweetened drink showed only slightly reduced glucocorticoid levels.
Yvonne Ulrich-Lai, a psychiatrist who led the study, said: "Glucocorticoids 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."
She said the findings could be of use in reducing human stress levels, from physical causes such as illness or injury, or psychological causes such as public speaking or coping with the death of a loved one.
Dr Ulrich-Lai added: "Finding another way to affect the body's response to stress and limit glucocorticoid production could alleviate some of these dangerous health effects."
Dr Ulrich-Lai said sweets, especially those made from sugar rather than artificial sweeteners, might be the answer.
"The sweets we are talking about are not the low-calorie, sugar-substitute variety.
"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."
Professor James Herman, who also worked on the study, added: "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."
Amanda Johnson. a dietician with the British Dietetic Association, said: "This research is interesting, but we would need to see more research on the mechanisms involved, and on the effects of sugary foods and drinks on stress in humans, before drawing any firm conclusions."
She added: "In the meantime, it's important to remember that there are many factors involved in stress and it is unlikely that simply eating sugary foods will alleviate the symptoms of stress in humans.
"Excessive intake of sugary foods is not recommended; sugary foods do taste great and it can be tempting to over-indulge, which could lead to a high energy intake.
"For optimal health go for a balanced diet that is low in fat, salt and sugar and have plenty of fruits and vegetables, and keep as active as possible."