The study involved tracking people's food options in a simulated supermarket depending on how hungry they were feeling.
A total of 62 paid people participated in the first part of the study, half of them were told not to eat anything 5 hours prior to doing their shopping. However, the other half were given a plate of Wheat Thins to satisfy their hunger. In some cases they were given crackers so they would no longer feel hungry.
The follow-up field study looked at purchasing habits at different times of the day - when they would most likely be hungry, such as before dinner - among 82 people.
The results revealed that the participants who were hungry when they made their purchases were more inclined to buy products that were higher in calories. The difference between the total number of foods selected was only marginal.
In addition, the field study shoppers who bought their groceries at times when they were most likely to be hungry (between 4 pm and 7 pm) bought fewer low-calorie food options and more high-calorie options compared to those who bought their products at times when they were less likely to be hungry (between 1 pm and 4 pm).
The authors of the study concluded:
"Even short-term food deprivation can lead to a shift in choices such that people choose less low-calorie, and relatively more high-calorie, food options. Given the prevalence of short-term food deprivation, this has important health implications."
Amy Yaroach, the head of the Gretchen Swanson Center for Nutrition in Omaha, Nebraska, said: "Even short-term fasts can lead people to make unhealthy food choices. 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."
Yaroach added that the findings have huge relevance for everyday shoppers.
Some experts speculate that this trend may well stem from an evolutionary time when people would often seek out high-calorie foods after a long period without eating. Simply put, if we are very hungry we are not going to be going out looking for lettuce, but rather look for options that are high in calories.
Eating something light before grocery shopping, which would help mitigate hunger, could be a good way of ensuring that people don't opt for such high-calorie products.
Healthy grocery shopping can seem daunting, however, according to The May/June 2012 issue of the Journal of Nutrition Education and Behavior, people benefited significantly from a 10-minute long counseling session from a nutrition educator, who provided the participants with an overview on how to read nutrition labels and instructions on how to use the 5 nutrition shelf signs that emphasize foods included in the Heart Healthy and Immune Booster categories.