November 18, 2019
To help guide research into foods that people might be overconsuming because they are so tasty (palatable), scientists have developed the first quantitative definition of "hyperpalatable".
They hope the research community can validate the definition to move the field forward and be better able to understand mechanisms that may be driving overeating and obesity.
"This study presents the first quantitative definition of hyperpalatable foods, which is based on combinations of key ingredients linked to palatability," said Terra L. Fazzino, PhD, who reported the findings during a symposium of top papers at Obesity Week 2019.
A hyperpalatable food is one where the synergy between components of the food — such as fat, sodium (salt), sugar, and carbohydrates — makes it tastier than it would otherwise be, Fazzino, of the Cofrin Logan Center for Addiction Research and Treatment, Department of Psychology, University of Kansas, Lawrence, explained to Medscape Medical News.
In the study, which was simultaneously published in Obesity, researchers determined that 62% of foods in the United States are hyperpalatable — including foods that do not come readily to mind as being super tasty.
Easy Access to Hyperpalatable Foods Drives Obesity
The editors of Obesity selected the study for inclusion in the top papers because of its novelty, Donna H. Ryan, MD, session co-chair and associate editor-in-chief of Obesity, told Medscape Medical News.
"We believe that one of the drivers of the obesity epidemic is ready access to energy-dense, hyperpalatable foods," said Ryan, who is professor emerita, Pennington Biomedical Research Center, Louisiana State University, Baton Rouge.
"To understand this, think about candy bars, salty chip snacks, and cookies, and how pleasurable it is to eat them and how fast one can accrue lots of calories by eating them," she said.
This work fills a need for a standardized definition of hyperpalatability, she noted, but as the authors readily admit, more needs to be done.
According to Ryan, we "need more studies looking at the characteristics of foods that make them hyperpalatable and encourage overconsumption. Only then will [the definition]...be ready for clinical use to help patients avoid these foods which encourage overeating."
What Are Hyperpalatable Foods?
Fazzino explained that hyperpalatable foods "can activate our brain reward neurocircuitry, which can create a highly rewarding experience that can make these foods difficult to stop eating, even when we feel full."
"It has been widely publicized...that the food industry has well-established food formulas based on combinations of fat, sugar, sodium, and carbohydrates that are designed to maximize palatability and consumption," Fazzino and coauthors write in their article.
However, the lack of a uniform definition for highly palatable food "is a serious limitation" in the field of obesity and nutrition research, they add, because definitions vary and include nonstandardized terms like "dessert" or "fast food".
Researchers identified descriptors of palatable solid foods in 14 scientific articles, and from these, using nutrition software, they created the new definition based on foods containing specific quantities of either fat/sodium, fat/sugar, or carbohydrates/sodium.
They defined hyperpalatable foods as those that contain:
- Fat and sodium (> 25% kcal from fat, ≥ 0.30% sodium by weight), for example, bacon and pizza; or
- Fat and simple sugars (> 20% kcal from fat, > 20% kcal from sugar), for example, cake and ice cream; or
- Carbohydrates and sodium (> 40% kcal from carbohydrates, ≥ 0.20% sodium by weight), for example, bread and chips.
They determined that 4795 of 7757 foods (62%) in the US Department of Agriculture's Food and Nutrient Database for Dietary Studies (FNDDS), which is representative of the US food system, met these criteria.
Many "Reduced" Foods Meet Criteria for Hyperpalatable
Most of the hyperpalatable foods (70%) were tasty because of their fat/sodium content, 25% met the criteria for fat/sugar content, and 16% met the criteria for carbohydrate/sodium content.
Fewer than 10% of foods met the criteria for more than one of the three categories.
Of 443 items in the database labeled as having reduced or no fat, sugar, salt, or calories, 216 (49%) met the definition for hyperpalatability.
"Most notably," 102 of 127 items (80%) labeled as reduced fat or calories met the criteria for hyperpalatable food.
Vegetables cooked in creams, sauces, and fats also met the criteria, illustrating how food preparation/processing, and not necessarily the food itself, can be key to determining whether it is hyperpalatable.
If 'Hyperpalatable' Is Validated, Should FDA Regulate Such Foods?
"If in the future, a body of evidence from the scientific community builds to support the hyperpalatable food definition we propose, there are several potential uses of our findings," said Fazzino.
The US Food and Drug Administration (FDA) "could require labeling of foods as hyperpalatable to alert consumers as to what they may be eating, but to [also] preserve consumer choice," she said.
The FDA could also potentially "regulate specific combinations of ingredients to decrease the chances that people find these foods difficult to stop eating [even when they are full]," Fazzino noted. "For example, they could limit the percentage of sodium in foods to less than 0.3% per gram per serving, if the food also contains more than 25% of calories from fat."
In the meantime, clinicians and the general public should be aware of certain combinations that make food more palatable and could lead to overeating.
"Keeping in mind that hyperpalatable foods contain multiple ingredients that enhance palatability," Fazzino said, "people might examine whether foods they eat contain multiple ingredients such as fat and sodium, particularly at high levels."
'Don't Eat Anything Your Grandmother Wouldn't Recognize'
Foods that would not be expected to be hyperpalatable are ones that occur naturally and have limited additional ingredients, such as a fresh apple.
"Michael Pollan [a US author who has written about the food industry] had a great message when he said, 'Don't eat anything your great grandmother wouldn't recognize as food,'" Fazzino remarked. "I think that recommendation applies well in this case too."