(CBS News) Starving for a bite? You probably shouldn't shop at a grocery store if you have an empty stomach, new research suggests.
A research letter published in JAMA Internal Medicine on May 6 shows that hungry grocery shoppers are more likely to buy higher-calorie food items.
Sixty-eight participants were asked to refrain from eating five hours prior to the study. Some participants were given Wheat Thin crackers so they would not feel hungry. Then, all participants went shopping in a simulated online grocery store with no prices.
The hungry people purchased on average 2.84 snacks, 1.40 dairy items, 2.80 grocery items and 1.20 meats. They put an average of six high-calorie items in their baskets. They also selected on average eight low-calorie products.
The people who had crackers to satiate their appetite also purchased eight low-calorie options on average. They bought 2.44 snacks, 1.56 dairy items, 2.81 grocery items and 0.95 meats, so there was no significant difference in the number of total items selected. However, they only selected four high-calorie items.
A second experiment followed 82 subjects as they shopped at various times when they were most likely to be full or hungry.
Those who shopped between 4 p.m. to 7 p.m. -- when they were more likely to be hungry -- purchased fewer low-calorie food than high-calorie ones, compared to people who were more likely to be full. Hungry shouppers bought 8.21 low-calorie items and 3.81 high calorie items. Their full counterparts who went shopping after lunch between 1 p.m. and 4 p.m. bought 11.2 low-calorie items and 2.69 high-calorie items on average.
"It's known that hungry people buy more food in the grocery store, but what happens more is that people shift their shopping patterns to contain more high-calorie foods," Aner Tal, a post-doctoral research fellow at Cornell University's Food and Brand Lab, told HealthDay. "When you are hungry, you think high-calorie food can provide you with more energy."
He added that dieting by skipping meals may not be a good idea. You may try to unconsciously make up for it by purchasing higher calorie foods at the supermarket, he said.
"Even short-term fasts can lead people to make unhealthy food choices," Amy Yaroch, head of the Gretchen Swanson Center for Nutrition in Omaha, Neb., told Reuters. She was not involved in the study.
"Don't go shopping when you're hungry and you don't have a list, because you're just going to buy all sorts of junk food," she added.
Tal now wants to look into whether eating a snack before grocery shopping will help curb your calorie-buying appetite.
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