Obesity may not just lead to diabetes, high blood pressure, and other health risks. New research suggests that a fatty diet may cause loss of smell, The Independent reports. Researchers studied mice on high-fat diets for 6 months, training them to associate certain smells with different things. Whereas those on healthy diets quickly caught on, obese mice were slow at learning which smells were associated with rewards. The same study, published in The Journal of Neuroscience, also found that overweight mice had only 50% of the neurons normally used to help distinguish odors.