▎WuXi AppTec Content Team Editor
Let’s be honest, when you’re craving something bland, low in sugar, is it hard to eat or even swallow? I finally made up my mind to lose weight, but I gave up because I couldn’t stand the bland food.
The biggest hindrance to this may be that your tongue is already trapped in sugar, which dulls your tongue for sweetness due to the high doses of added sugar in many foods.
New research in Current Biology uses mice to find that a high-sugar diet reduces the ability of the taste system to perceive sweetness, mice fed a high-sugar diet for a short period of time , the brain’s response to delivering sweet taste information from the tongue dropped by about half.
In fact, a study a few years ago found that giving some volunteers a diet low in sugar stimulated stronger sugar cravings. “Additionally, some of our results in fruit flies show that sugar can reprogram their taste cells to reduce the response of the associated nerves,” said Monica Dus, a professor of molecular biology at the University of Michigan.
This time, Professor Dus and colleagues wanted to see if a similar phenomenon could occur in mammals. They selected a group of rats, one group ate normal food, but the drinking water was replaced with sugar water, and the control group received normal tasteless drinking water.
Image source: 123RF
After about 4 weeks, the researchers tested the response of the rat tongue to different tasting liquids in the associated taste nerves, which transmit taste information from taste bud cells on the front of the tongue to brain.
The tested liquid tastes included sweet, bitter, sour and salty, and the researchers also added the rat’s response to touch and cold. With the help of the comparison of the control rats, it can be seen that the taste responses of the rats in the experimental group to all other tests were unchanged except for the sweet solution.
But the rats in the experimental group had a direct 50% decrease in their neural response to sweetness, “This is a very significant change, it only takes 4 weeks to produce Such results,” Professor Dus said.
▲Consumption of sugar water for four consecutive weeks reduced the sensitivity of rats to sweetness (Image source: Reference )
This may be the root cause of our rapid dependence on sugar, and within a month, the entire taste system becomes dulled to sweetness. But don’t worry, if you can really make up your mind to quit sugar, then sticking to your tongue for a while will pay you back.
The rats that had been spoiled with sweet water were switched to regular water at the end of the experimental period.After about 4 weeks, the rat’s gustatory nerves responded to sweet taste. Sensitivity is restored. The authors point out that this is good news for some people who need to make a change, as long as you keep eating light, you can restore your sensitivity to sweetness.
Through analysis, the researchers found that there was no change in the number of taste buds in the structure of the tongue papilla where the taste buds of the rats in the experimental group were located, which also proved why other taste responses did not change.
▲The taste bud structure of the experimental rats basically did not change, and the root cause was that there were fewer taste bud cells sensitive to sweetness (Image source: Reference )
But a closer inspection of the taste buds reveals a different picture. Rats fed with sugar water had significantly fewer taste bud cells that detect sweetness . Dr. Dus plans to explore how this reduction affects the transmission of sweetness messages and, in turn, how the brain behaves.
At least from their experiments with fruit flies, the authors saw that reduced sensitivity to sweetness reduces dopamine release, reduces satiety and leads to overeating. This is probably the feeling that the more sweet you eat, the more you can’t stop.
“You have to remember that your taste system is malleable,If you re-choose your food and cut back on sugar, your taste buds will love those foods very quickly,” Professor Dus said.
 Hayeon Sung et al, High-sucrose diet exposure is associated with selective and reversible alterations in the rat peripheral taste system, Current Biology (2022). DOI: 10.1016/j.cub .2022.07.063
 A high-sugar diet decreases ability to sense sweetness in rats. Retrieved October 17, 2022 from https:https://medicalxpress.com/news/2022-10-high- sugar-diet-decreases-ability-sweetness.html