My Executive


    Sep 17, 2013

    Stayed up all night? Don't buy groceries

    IF YOU have been keeping late hours, try to stay away from the supermarket.

    A new Swedish study has found that sleep-deprived shoppers spend more money on junk food than when they have had a good night's rest, AFP Relaxnews reported.

    Previous studies have shown that one night of bad sleep can lead to increased blood levels of ghrelin, a hormone that increases hunger the next day.

    What the Swedish study found is that ghrelin levels were not associated with food purchasing. Rather, it is sleep deprivation that could trigger other mechanisms, such as impulsive decision-making.

    "We hypothesised that sleep deprivation's impact on hunger and decision-making would make for the perfect storm with regard to shopping and food purchasing," said lead author Colin Chapman of Uppsala University in Sweden, who was quoted by AFP Relaxnews.

    "(This leaves) individuals hungrier and less capable of employing self-control and higher-level decision-making processes to avoid making impulsive, calorie-driven purchases."

    The researchers looked at 14 healthy men who took part in two situations: stay awake for one night, then go grocery shopping the next morning, or sleep as usual and then go shopping.

    With a budget of US$50 (S$63), the participants were instructed to buy as much as they could out of a possible 40 items, comprising 20 junk foods and 20 healthier options, said AFP Relaxnews.

    While the research shows the most extreme example of sleep deprivation - staying up all night - sleeping a few hours less every now and then could play a role in cutting into one's resistance to fatty foods, a concept backed by previous research.