Your two-year-old's health is closely tied to how much he eats, what he eats, and how active he is. Obesity and weight-related diseases affect about 20 percent of all children today. These problems include diabetes, asthma, bone disorders, and other health problems. It is very rare for weight-related problems to be genetic in origin. Overweight children are almost always overweight because of lifestyle — and very young children have only the lifestyles that their parents or other caregivers create for them.