Your morning staple can be messing with your taste buds.
In the study, researchers recruited 107 people and had them take part in two experiments: In one, they drank decaffeinated coffee supplemented with 200 milligrams (mg) of caffeine—roughly the amount in a strong cup of coffee.
In the second, they drank just decaf coffee. Afterwards, the researchers asked them to rate the taste of the coffee, as well as that of other sugary solutions.
The results? When the people drank the caffeinated coffee, they rated their brew as less sweet than when they drank the decaf.
They also rated other sugary solutions they tested afterwards as not as sweet, too—despite no difference in other tastes, like bitter, sour, salty, or umami.
“When you drink caffeinated coffee, it will change how you perceive taste—for however long that effect lasts,” study author Robin Dando, Ph.D., explained in a statement. “So if you eat food directly after drinking a caffeinated coffee or other caffeinated drinks, you will likely perceive food differently.”
So what’s going on? Caffeine binds on adenosine receptors in your body, with interferes with your body’s signal to feel sleepy.
That’s why caffeine makes you feel more awake. But binding on these receptors also decreases your ability to taste sweetness, which may actually make you desire it more.
And if your sweet tooth runs unchecked, that may make you more likely to seek out sweet stuff, which can be bad for your waistline.
If you can’t skip out on your daily caffeine fix, at least try taking a brisk walk after your cup of joe: Walking for just 15 minutes can reduce your cravings for candy and other sweets, as we reported in the past.