"There are the little things that we can do to just make our diets healthier, and one of them is the simple idea to just put the healthy foods closer to you and you'll find you can use your laziness to your advantage," Gregory Privitera told Reuters Health.
Privitera, a psychology researcher at Saint Bonaventure University in Bonaventure, New York, led the study, which he says was inspired by experience with his kids.
"Every time my kids would tell me, 'I want a snack,' I would point to the bowl of fruit on the kitchen table and just say, 'go at it - you can have as many as you want.,' and they'd say, 'oh I don't want that,' and I'd say, 'okay then, make your own snack," Privitera recalled.
"And then lo and behold, they'd come walking by a minute or two later with fruits and vegetables in their hands," he said.
"I realized they're not going to make their own snacks, they're going to take what was easier to get, the fruits on the kitchen table," he said.
Privitera said early studies by Brian Wansink at Cornell University in New York using bowls of candy were also an influence.
"He found the closer you put the bowl of candies, the more that people ate of them," Privitera said.
Privitera said he and his coauthor Faris Zuraikat wanted to know whether the type of foods used in such a study made a difference, so they did a similar experiment with healthier foods.
"The short answer is no - we can put healthy foods in and move them closer to a participant and they'll eat more of that," Privitera said. "We showed that last year in a study with carrots and apples."
To go beyond choices between two healthy foods, the researchers recruited new study participants and added buttered popcorn to the mix.
For the new study, the researchers selected 56 men and women who were, on average, 19 years old and in good health. Twenty were of a healthy weight, 21 were overweight and 15 were obese.
One at a time, each participant was seated at a kitchen table where a bowl of apple slices and a bowl of popcorn had been placed; one was within arms' reach and the other about twice as far away.
About a third of the participants had the apples placed closer to them, another third had the popcorn placed closer to them.
The remaining third of the participants served as a control group and sat at tables where the apples and popcorn were the same distance away.
In each case, a researcher said they had to leave the room for a few minutes to go get a questionnaire and that it was okay for the participant to eat the food while the researcher was gone.
After six minutes, the researcher returned, recorded the amounts of apple and popcorn that were eaten, and asked the participant to rate each food from 1 to 5, with 5 representing "liked a lot."
Overall, participants tended to say they preferred popcorn but those who were closer to the apples ate, on average about 1.5 ounces of apple slices, while those closer to the popcorn only ate 0.2 ounces of apple. The control group ate about 1 ounce of apple slices.
The participants closest to the apples also ate the least amount of popcorn - about 0.7 ounce, compared to 0.26 ounce for those seated closer to the popcorn, and 0.33 ounce for the control group.
The findings were published in Appetite.
"The takeaway from this is that you can set up the food environment that you and your children live in to make it easier to grab the healthiest foods," Privitera said.
The idea is that small changes can add up, he added. For example, a person who normally reaches for an unhealthy snack five or six times per day could switch to eating fruit.
"You're looking at, over the course of a year, substantially reduced energy intake and an overall healthier diet because you're eating a lot more fruits and vegetables simply by making them more convenient and easy to reach," he said.
Lori Rosenthal, a dietician who works with weight-loss surgery patients at Montefiore Medical Center in New York told Reuters Health that proximity does play a role in the foods people choose.
"When we're hungry, we wind up choosing convenience and a lot of times we choose convenience over health when there's not a healthy option there," said Rosenthal, who was not involved in the new study.
She said having fresh fruits out on the counter is one way to keep healthy foods in close reach.
"Your eye goes to them first, you see the bright colors - it's not just having them close to you, they're also enticing," she said.
Rosenthal also advised avoiding the temptation to eat unhealthy foods by keeping them out of the house.
"If you have trigger foods, or specific foods you can't control yourself around, you don't want them within close proximity to you, especially in your house," she said.