Sleep deprived? Don't hit the grocery store

If you're running low on steam because of a sleepless night, it's probably best to avoid grocery shopping.

A Swedish study published in the journal Obesity found that people who were sleep deprived were more likely to purchase foods higher in calories - and more of them - than people who had gotten plenty of rest.

The research team was curious to know if food-purchasing choices were affected by impaired higher-level thinking, which can be a result of sleep deprivation.

The 'perfect storm'

Similar to a study from UC Berkeley earlier this year, the research showed that a sleepless night affects areas of the brain that respond to motivation, reward and pleasure.

First author Colin Chapman, MSc, of Uppsala University, explained:

We hypothesized that sleep deprivation's impact on hunger and decision-making would make for the "perfect storm" with regard to shopping and food purchasing - leaving individuals hungrier and less capable of employing self-control and higher-level decision-making processes to avoid making impulsive, calorie-driven purchases.

Chapman and his team gave 14 normal-weight men a fixed budget of about $50. The men were then told to purchase as much food as they could in a mock grocery store that carried 40 items - 20 that were high-calorie foods and 20 that were low-calorie foods. The researchers varied the prices of the high-calorie foods to determine how sleep deprivation would affect food purchasing. The participants were given breakfast to help minimize purchases based on immediate hunger.

Men buy more calories, show higher ghrelin levels

Sleep-deprived men were shown to buy significantly more calories - about 9 percent - than they did after a night of sleep. Men who didn't sleep also had higher levels of ghrelin, a hormone that regulates hunger.

The bottom line? Get more sleep so as to avoid making poor food purchasing decisions, the authors concluded.

"Our finding provides a strong rationale for suggesting that patients with concerns regarding caloric intake and weight gain maintain a healthy, normal sleep schedule," said Chapman.

Source: Wiley