Study: Obese individuals perceive taste differently, enjoy food more

IOWA CITY, Iowa — Obesity is becoming an increasingly common condition among Americans, with an astounding 30% of the U.S. population classified as obese. Though usually caused by a variety of factors, such as genetics and lack of exercise, there’s no denying that the amount of food someone eats is a major determining factor. While it’s generally assumed that people of all sizes taste and enjoy food in the same ways, a new study conducted at the University of Iowa has found that obese individuals actually perceive initial tastes from food differently and gain more satisfaction from eating.

Researchers theorize that this heightened sensitivity to taste may result in obese individuals developing a habit of overeating during meals.

“Taste perceptions may lead to overeating. If people with obesity have different taste perceptions than nonobese people, it could lead to better understanding of obesity and possibly designing new approaches to prevent obesity,” explains lead investigator Dr. Linnea A. Polgreen in a release.

It’s already been established that it’s common for people to experience diminishing marginal taste perception, more commonly referred to as sensory-specific satiety, while eating. Basically, this means that the more you eat of the same food item, the less you will enjoy its taste.

So, researchers set out to determine if marginal taste perceptions differ among people of normal weight, overweight people, and obese people. Additionally, the study also examined if knowledge of a food’s nutritional information impacts marginal taste perception.

In all, 290 adults between the ages of 18-75 took part in the study; 161 with normal BMI, 78 considered overweight, and 51 classified as obese. Each participant was given one piece of chocolate at a time, but could ask for as many chocolates as they wanted. Some participants ate as little as two pieces, while others ate over 50. Half of the participants were also given nutritional information on the chocolate, while the other half were given no specifics.

In general, all three groups enjoyed the chocolate pieces less as they continued to eat them. However, obese participants showed higher levels of initial taste perception, rated subsequent pieces of chocolate higher than the other groups, and their ratings declined at a more gradual rate. Prior knowledge of nutritional information didn’t seem to make any difference in taste perception.

“In our study population, people with obesity reported a higher level of satisfaction for each additional piece of chocolate compared to nonobese people. Thus, their taste preferences appear markedly different,” comments co-investigator Aaron C. Miller, PhD.

The study is published in the Journal of the Academy of Nutrition and Dietetics.