Study finds caffeine makes food seem less sweet

A study has found that caffeine, the widely consumed stimulant, tempered taste buds temporarily, making food seem less sweet.

Caffeine is a powerful antagonist of adenosine receptors, which promote relaxation and induce sleep.

When the receptors are awakened it decreases the ability of people to taste sweetness, according to researchers.

"When you drink caffeinated coffee, it will change how you perceive taste - for however long that effect lasts," said Robin Dando, assistant professor at Cornell University in the US, PTI reported.

"So if you eat food directly after drinking a caffeinated coffee or other caffeinated drinks, you will likely perceive food differently," said Dando.

One group sampled decaffeinated coffee with 200 milligrams of caffeine added in a laboratory setting, to make a strong cup of coffee, according to the study published in the Journal of Food Science.

The other group drank only decaffeinated coffee. Both groups had sugar added but the study participants who drank the caffeinated brew rated it as less sweet.

According to Dando, coffee also alters how the brain registers certain tastes.

The participants reported their level of alertness in a different part of the study, and estimated the amount of caffeine in their coffee.

In the second part of the experiment, participants rated their level of alertness and estimated the amount of caffeine in the coffee they consumed. The researchers found that participants could not determine whether they had a caffeinated or decaffeinated beverage, with all reporting the same increase in alertness on average.

This part of the study revealed that coffee could have a placebo effect, according to Dando: the simple act of drinking coffee could make people think they are more awake.

"We think there might be a placebo or a conditioning effect to the simple action of drinking coffee," said Dando.

"The act of drinking coffee - with the aroma and taste - is usually followed by alertness. So the panelists felt alert even if the caffeine was not there," said Dando.

"What seems to be important is the action of drinking that coffee. Just the action of thinking that you have done the things that make you feel more awake, makes you feel more awake," he said.