Scientists have warned most foods eaten in the U.S.— including some marketed for weight loss—contain ingredients which make people want more.
These hyper-palatable foods contain certain combinations of sugar, fat, salt, and carbohydrates which tap into the brain’s reward system and make it hard for us to stop eating them, according to scientists who published a definition in the journal Obesity.
Such items fall into three categories. Foods where at least 25 percent of the calories come from fat and salt makes up 0.03 percent salt of their weight; those with at least 20 percent calories from fat and 20 percent from sugar; and items getting 40 percent of calories from carbohydrates and 0.2 percent of weight from salt.
Foods deemed hyper-palatable include hotdogs, which marry salt and fat; brownies which bring together fat and sugar; and pretzels which contain salt and carbohydrates.
Tera Fazzino, assistant professor of psychology at the University of Kansas who lead the study, told Newsweek that while hyper-palatable foods have been loosely described foods in the past, there wasn’t a scientific definition until now. This limited their study and the potential roll-out of policies to tackle obesity, he argued.
“For example, while we can’t regulate categories of foods, such as desserts, we could provide specific information to legislators regarding the specific levels of ingredients that may enhance palatability in a way that may make foods difficult to stop eating,” Fazzino said.
To come up with the definition, researchers used special software to see which ingredients 7,757 foods sold in the U.S. shared. They reviewed 14 existing studies on foods manufactured to contain ingredients which make them more appealing.
Based on the new criteria, the team found 62 percent of foods sold in the U.S. was hyper-palatable. Of those, 70 percent were high in fat and salt, a further 25 percent were high in fat and sugar, and 16 percent featured a lot of carbohydrates and salt. Fewer than 10 percent of the items fell into more than one category.
Among foods labelled as having no, reduced, or low levels of sugar, fat, sodium, or calories, 49 percent were hyper-palatable
Fazzino, who is also associate director of the Cofrin Logan Center for Addiction Research and Treatment at KU’s Life Span Institute, told Newsweek: “These findings indicate that many foods marketed for weight management may have characteristics of enhanced palatability.”
The team haven’t yet come up with a definition suitable for public use, said Fazzino, but he suggested “people might examine whether foods they eat contain multiple ingredients such as fat and sodium, particularly at high levels.”
“Foods that would not be expected to be hyper-palatable are ones that are naturally occurring and have limited additional ingredients, such as a fresh apple,” he said.
“[Writer] Michael Pollan had a great message when he said ‘don’t eat anything your great grandmother wouldn’t recognize as food.’ I think that recommendation applies well in this case too.”
Fazzino said in a statement that if evidence emerges to suggest such foods are problematic for society, items could one day be labelled as hyper-palatable.
“We might even think about the restriction of certain types of foods that are available in certain places—for example, in elementary school cafeterias for kids whose brains are still developing and who may be impacted by these types of foods’,” he said.