OBESITY CAN CHANGE OUR SENSE OF TASTE

Previous studies have shown that obesity can lead to alterations in the brain, impairing the blood-brain barrier and affecting memory and learning skills; according to the data, the changes in the blood-brain barrier may encourage overconsumption of fatty foods and those full of refined sugar, resulting in what researchers call “a vicious cycle.”

In this new study, conducted by biologists at the University of Buffalo, scientists have found that being overweight alters our sense of taste at the most fundamental level: by changing how our tongues react to different flavors.
Researchers studied mice and found that severely overweight animals were less able to taste sweet food. The study, published in the journal PLoS ONE, may help solve the mystery of how obesity can affect our relationship to food.
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 in a press release: "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."

To investigate, the researchers looked at the tongues of severely overweight lab mice. Intriguingly, they found that the average tongue’s reactive capacity differed greatly from that of normal mouse tongues. "The obese mice have fewer taste cells that respond to sweet stimuli, and they don't respond as well," Medler said. So far, the researchers have yet to determine whether this deficiency helps sustain obesity. According to Medler, it is possible that an inability to detect sweets may cause obese people to compensate with more food.
Learning more about the connection between taste, appetite and obesity is important, she said, because it could lead to new methods for encouraging healthy eating.
"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," she said. "These cells are out on your tongue and are more accessible than cells in other parts of your body, like your brain."

Medler and her colleagues’ study is the latest in a growing series of inquiries into biological factors thought to drive the obesity epidemic. In a study published earlier this year, another team of researchers described how a faulty appetite hormone may make it more difficult for obese people to limit their eating. Like the dulled taste cells, the misfiring glucagon hormone messes with the patient’s ability to achieve satiety, or fullness.

According to the Center for Disease Control and Prevention (CDC), obesity currently affects one-third of American adults. The condition is associated with a heightened risk of developing heart disease, stroke, type 2 diabetes and certain cancers. The agency estimates that the annual medical cost of the epidemic is $147 billion.  

Sources: http://esciencenews.com/, http://www.medicaldaily.com/