No smell sense, less weight... but the reason is unexpected
Smell affects eating habits. If you can smell your food, you will enjoy more and eat more. If one doesn't have a sense of smell, he/she will likely not enjoy the food as much, so he/she will eat less and probably lose weight in the process. Prof. Andrew Dillon's research backed the assumption: no smell sense, less weight. But for a completely different reason.
What was the study about?
The cell biologist at the University of California Berkeley started a study on the effect of sense of smell on weight in mice. His hypothesis was that mice without the sense of smell would weigh less even while on healthy, nutritious diet. He was right. But the factor was unexpected: for some reason, those without a sense of smell burned more energy.
How was it carried out?
The scientists took two groups of adult mice: one normal adults, and the other genetically-modified ones which had no smelling capacity. Both were fed on regular and high-fat diets for three months. Contrary to expectations, both groups ate and exercised in similar amounts.
What did they find?
On the regular diet, mice that couldn't smell were found to have slightly less weight than the others. But on the high-fat diet, the difference was much clearer. In fact, those without a sense of smell weighed 16% less than the normal ones. Going one step further, they found that if sense of smell was removed from overweight mice, they started losing weight.
So how did that happen?
Mammals have two kinds of fat tissue: brown, which makes heat, and white, which stores energy. Mice have more brown fat than humans. Researchers found those without a sense of smell were using more brown fat tissue. Dillon agrees more research is needed, but says weight gain is about more than what or how you eat; it's also about "how you're perceiving food".
