People who are overweight taste food differently and may be less sensitive to sweet flavours.American researchers found that being obese can change how food tastes on our tongues.They studied mice and found that severely overweight animals were less able to taste sweet food.The study may help solve the mystery of how obesity can affect our relationship to food, as well as helping us to find new cures for the condition.Compared with other slim mice, the fat mice had fewer taste cells that responded to sweet stimuli, and the reactions were weaker.Dr Kathryn Medler, of the University of Buffalo, said: 'Studies have shown that obesity can lead to alterations in the brain, as well as the nerves that control the peripheral taste system, but no one had ever looked at the cells on the tongue that make contact with food.'What we see is that even at this level - at the first step in the taste pathway - the taste receptor cells themselves are affected by obesity. 'The obese mice have fewer taste cells that respond to sweet stimuli, and they don’t respond as well.'How an inability to detect sweetness might encourage weight gain is unclear, but past research has shown that obese people crave sweet food. Dr Medler said it is possible the inability to taste sweetness leads overweight mice to eat more than their leaner counterparts to satisfy their cravings.'If we understand how these taste cells are affected and how we can get these cells back to normal, it could lead to new treatments,” said Dr Medler. 'These cells are out on your tongue and are more accessible than cells in other parts of your body, like your brain.'The new study, published in the journal PLOS ONE, compared 25 normal mice to 25 of their littermates, who were fed a high-fat diet and became obese.Researchers used a process called calcium signalling to work out when the mice’s tastebuds recognized a certain taste.When the cells detect a particular taste, there is a temporary increase in the calcium levels , which the scientists measured.They found that taste cells from the obese mice responded more weakly not only to sweetness but to bitterness as well. Taste cells from both groups of animals reacted similarly to umami, a flavour found in savoury foods.(dailymail.co.uk)ANN.Az