March 11, 2009

Salt helps put people in better mood

Researchers at the University of Iowa suggest that the reason many people consume too much salt is because it puts people in a better mood.

Psychologist Kim Johnson and colleagues found that when rats are deficient in sodium chloride -- common table salt -- they shy away from activities they normally enjoy, like drinking a sugary substance or pressing a bar that stimulates a pleasant sensation in their brains.

Things that normally would be pleasurable for rats didn't elicit the same degree of relish, which leads us to believe that a salt deficit and the craving associated with it can induce one of the key symptoms associated with depression, Johnson said in a statement.

Past research showed that worldwide average for salt intake per individual is about 10 grams per day, which is greater than the U.S. Food and Drug Administration recommended intake by about 4 grams -- and may exceed what the body actually needs by more than 8 grams, Johnson said.

Today, 77 percent of U.S. salt intake comes from processed and restaurant foods, such as frozen dinners and fast food, Johnson said.

Johnson explained that one sign of addiction is using a substance even when it's known to be harmful -- many people are told to reduce sodium due to health concerns, but they have trouble doing so because they like the taste and find low-sodium foods bland.

The findings were published in the journal Physiology & Behavior.