Have a Sweet Tooth? Your Genes May Be to Blame.

Here’s something to chew on next time you make a grab for that cookie: some of us may have a slight genetic predisposition to craving sugary treats.

Now, now. Of course, it’s not that simple. Many factors fold into our craving of, and delight from, sugar. Exhaustion and poor sleep play a big part, for one. So do neural feedback loops and the sensory experience that a beautiful dessert conveys. Yet, new research may have confirmed that it’s not all in your head, that feeling that you Must. Have. That. Ice. Cream.

Sweet cravings may be programmed

Scientists are researching the science of appetite, food regulation and sugar cravings and they are finding that certain gene variants are linked to an increased craving for sugar. Scientists are also investigating why some people with high sugar needs still have lower body mass indexes. All of this research lays the foundation for personalized diet plans.

An international research team delved into the genes of more than 6,500 Danish people. These folks were originally signed up for a study that focused mainly on heart disease. People who had one of two variants of the FGF21 gene were approximately 20 percent more likely than others to seek sugary substances. In other words, the idea of a sweet tooth isn’t necessarily just a habit thing; it sits in your molecular core.

Turns out, FGF21 tells your body to make a hormone specifically associated with food regulation. These new sugary clues give scientists hints that it may guide the human appetite, as well. It also opens up the idea that perhaps the liver plays a larger role in appetite, too, since it’s the liver that secretes the FGF21 hormone, controlling insulin resistance and telling your brain how to feel (or, what foods to go after).

To figure all this out, researchers reviewed volunteer reports about their food preferences, comparing them to their cholesterol levels and blood sugar tests at the same time. Participants with a strong liking for sugar—and who took more sugary foods in—were more likely to have one of two FGF21 variants. Note, these gene variants also had a weaker link to a higher intake for alcohol, and a daily smoking habit.

Questions remain

While this study gives clues about our yearning for sugar, many of the factors that control our food preferences and appetite levels remain a mystery. There’s some speculation that this gene variant may play around with a person’s response to “rewards” in the brain, making them continue to seek them out despite the higher sugar intake. Other unanswered questions: why do people with the FGF21 gene variants have lower body mass indexes (BMIs); an unexpected discovery given the link between sugar and obesity.

As scientists continue to explore our bodies’ pathways to food intake, our food preferences and our appetites, along with individual risk for disease and associated lifestyle choices, research such as this could open the door for hyper-personal nutrition plans. In the meantime, some of us may be hardwired for sugar.


Looking to curb your desire for sweets? Check out Health Ambition’s article on How to Stop Sugar Cravings.