 When they looked at hamsters, they actually found a higher risk of some type of food allergies. We don't fully understand why people develop food allergies at different ages, but we believe that there is both a genetic and an environmental component. Since we can't control our genes, environment and behavior are getting a lot of attention now. And since cats and dogs have other benefits as well, perhaps it's time to visit your local animal shelter. With Your Body, I'm ABC's Dr. Jennifer Ashton.