A new U.S. study has found that when consumers are provided with a graph displaying the nutritional content of their food, they purchase healthier items.

The research could be important for providing consumers with information on food in settings such as cafeterias or restaurants, where it can be difficult to quickly calculate the nutritional value of menu items and make a more informed decision.

To conduct their study, the team of researchers from the University of Illinois looked at consumers' purchasing behavior at the university's cafe when they were presented with the same nutritional information about the menu using two different methods.

During certain weeks of the 12-week study, consumers were given information about the nutritional content of menu items' in a two-dimensional graph format, and for other weeks in the numerical format.

The 2-dimensional graph showed the fiber, protein, saturated fat, and sodium per calorie values of food plotted out in color, as well as a target to inform consumers of the recommended dietary amounts of those nutrients per calorie of food.

The information was displayed where customers could see it before ordering, with nutrition facts such as how many calories to consume to maintain a healthy weight also on display.

Researchers observed that when the nutritional information was presented using the 2-dimensional graph consumers purchased fewer calories compared to when nutritional information was provided numerically, or not provided at all.

The team also saw that when the graph was present consumers purchased foods with more protein per calorie, with protein increasing by nearly 24 per cent when compared to no nutritional information, and increasing by 20 per cent compared to when nutritional information was presented numerically.

Manabu T. Nakamura, an associate professor of nutrition at U of I, commented on the results saying "Current nutrition labels provide comprehensive nutrient information, but unfortunately they're not working for consumers to help them make decisions in restaurants and grocery stores," with the team referring to the results seen in their study as a "clear success."

Nakamura also added that although the study concentrated on a select number of nutrients, other combinations of nutrients could also be plotted on the graph, with the team also hoping that food places such as restaurants, grocery stores, and dining halls could adopt the graph format for displaying nutritional information.

The team also envision a mobile app in the future, which would enable users to plot nutrients from a menu item onto the graph themselves, so they can make a more informed and healthier decision about what to order.

The findings were published in the journal Nutrition Research.