Taste sensitivity, thinness linked in study

TRENTON, N.J. – Could a sensitive palate be the key to a svelte figure?

Maybe, say researchers at Rutgers University and elsewhere who have found people especially sensitive to bitter compounds in broccoli and other foods tend to be thinner than others.

A Rutgers study, on nearly 50 women in their 40s, found “super tasters,” people most sensitive to bitter tastes, were 20 percent thinner than “nontasters,” those not sensitive to bitter tastes.

“People who are nontasters tend to like foods that are fattier, sweeter, hotter and more bitter,” said Beverly Tepper, a professor of food science at Rutgers.

“They tend to eat more fatty foods,” she said. “What we believe is that if nontasters pursue this kind of dietary pattern over time that this would lead to higher body weight.”

Super tasters instead appear to eat less food overall – be it high-fat foods or healthy, bitter vegetables, according to preliminary research.

Tepper’s study, which awaits publication, found super tasters had an average body-mass index of 23.5. Medium tasters had an average of 26.6, and nontasters an average of nearly 30.

Body-mass index measures weight relative to height. A BMI of 25 and above is considered overweight; 30 and higher is obese.

Tepper’s study is small, but it’s her fourth with similar findings, including one involving New Jersey preschoolers. That research found the nontaster kids preferred full-fat to low-fat milk and ate more added fats such as butter and salad dressing than the other children.

Tepper said the strongest association she’s found has been in middle-aged women. She said about 50 percent of Americans are medium tasters and 25 percent each are super tasters or nontasters.

Those classifications are actually based on sensitivity to a chemical, known as PROP for short, that is very similar to compounds that make foods like broccoli and brussels sprouts taste bitter. Some scientists dispute the association between sensitivity to PROP and body size, but researchers at Yale University and University of Connecticut have produced results similar to Tepper’s.

Laurie Lucchina, a former researcher and instructor at both schools who now does research for Gillette Co.’s oral care division, repeatedly tested taste and smell sensitivity of elderly women. “We found people who could taste PROP as more bitter were significantly thinner.”

She said super tasters generally perceive sweet, sour and salty tastes – not just bitter ones – more intensely than others.

Valerie Duffy, who teaches nutrition and dietetics at Connecticut, has produced similar findings and also shown that super tasters, compared with others, generally have more papillae, the tiny bumps on the tongue that hold taste buds. She said some research shows an association between eating habits and gene variations related to ability to taste bitter compounds.

Duffy said another scientist reported nearly four decades ago that people extremely sensitive to the bitter tastes of PROP tended to be lean, while nontasters were built like football players.

Little further research was done until the 1990s. Now numerous studies are investigating the connection.

Still, some researchers haven’t found the link between PROP and body size, including Richard Mattes, professor of foods and nutrition at Purdue University.

“I am a great skeptic of the role of PROP in food intake and body mass,” he said, partly because people sensitive to the chemical may not be turned off by bitter compounds in foods such as chocolate and coffee, where milk or other sweet flavors mask the taste.

Tepper, Lucchina and Duffy say they believe Mattes’ findings differ from theirs because he uses different methods to classify subjects’ taste perception.