Ever wonder why you gravitate toward ice cream, butter and French fries, no matter how hard you try to like low-fat foods?
The answer may be in your genes.
A study has found that a specific gene variation associated with how well people sense fat on the tongue is also linked with their preference for fat. The discovery, published in the journal Obesity, could have implications for how successful certain individuals are in losing weight, researchers say.
Previous research suggests that a protein called CD36, which helps fatty acids move across cell membranes, is an oral fat receptor that allows people to perceive fats as a taste sensation.
For their study, Kathleen Keller, assistant professor of nutritional sciences at Pennsylvania State University, and a team of researchers identified CD36 gene variations in 317 African-American adults, using DNA analysis of their saliva samples. They also tested the participants' ability to perceive fat by asking them to taste several salad dressings containing varying amounts of fat. Participants were also given a questionnaire to gauge their preferences for added fats and oils, such as butter, sour cream and mayonnaise, and high-fat foods, such as bacon, potato chips and doughnuts.
The researchers discovered that individuals with a certain variation in the CD36 gene perceived the salad dressings to be creamier, regardless of the actual fat content. The same individuals also expressed a greater preference for added fats and oils in the questionnaire.
Knowing who has this particular genetic variation could help nutrition experts prescribe higher-fat diets to those who naturally prefer high-fat foods, helping them achieve long-term weight loss, Dr. Keller says. "Sometimes when people try to make big, big changes in their dietary habits, it's too hard for them to comply," she says, explaining that sharply restricting fat for those who prefer high-fat foods may not work. "It's just simply too much change for them and they end up failing."