Adults who don’t routinely eat vegetables for lunch may be more likely to consume them if the vegetables are seasoned, a new study suggests.

People who seldom ate vegetables at lunch were 1.5 times more likely to select a seasoned vegetable than its unseasoned counterpart, researchers at the University of Illinois found in a study of more than 530 adults.

During the study, which was conducted over a three–week period in a cafe setting, one vegetable – broccoli, carrots or green beans – was offered each day as both a seasoned and an unseasoned selection. Customers who purchased a hot entree were offered a vegetable at no extra cost.

All diners, regardless of whether they took a vegetable, were asked to complete a survey that included questions about their eating habits, vegetable preferences and likelihood of purchasing a vegetable side dish if it were priced at $1.

Broccoli, carrots and green beans were chosen for the study because they are among the vegetables most frequently consumed by adults in the U.S., said the paper’s lead author, Joanna Manero, a graduate student in food science and human nutrition.

To prevent potential bias caused by labeling, the unseasoned vegetables were listed on the menu board as “steamed” carrots, green beans or broccoli rather than as “unseasoned,” according to the paper, published recently in the journal Appetite.

Diners in the study were significantly more likely to choose a seasoned vegetable – especially if the consumer was male and under 50 years old, the researchers found. However, the opposite effect was found with diners who routinely ate vegetables for lunch: They preferred the unseasoned selections.

Despite numerous public awareness campaigns aimed at enticing Americans to increase their consumption of vegetables for better health, many people still fall short of the amounts recommended by federal agencies and nutritionists, research has found. And those who do eat vegetables tend to eat them more frequently during their evening meal rather than at breakfast or lunch.

Herbs and spices may make vegetables more tempting for men and younger adults – who tend to eat fewer plant–based foods overall than do women and older adults, Manero said.

“Getting people to go from zero to even one serving is a big step forward in moving people to include vegetables in their daily diet,” said food science and human nutrition professor Karen Chapman–Novakofski, a co–author of the paper. “If you’re already eating vegetables at dinner, then perhaps that’s not the place we need to make that nutritional nudge.”

Most diners indicated that they liked carrots, green beans or broccoli somewhat or very much, whether seasoned or not. If the vegetable selections were priced at $1, diners indicated that they would be somewhat or very likely to purchase a broccoli selection (84 percent), the green beans (74 percent) or the carrots (64 percent).

When diners returned their trays, the researchers collected and measured the amount of waste to determine how much of the vegetables participants actually ate.

Diners wasted twice as much of the seasoned carrots as green beans and three times more carrots than seasoned broccoli, even though they reported they liked carrots about as much as the other two vegetables. The researchers hypothesized that diners may have disliked the cinnamon seasoning that was used on the carrots in the study.