Obesity is now a critical public health issue in North America. In a single generation, obesity rates in the U.S. have more than doubled. But the causes of obesity -- and therefore, the solutions -- are not necessarily simple.
The problem of obesity cannot be reduced simply to genetics, environments or learned behaviors. The obesity epidemic is the result of a variety of factors, and change requires a comprehensive approach.
Factors such as diet of course play a key role. But it is often more complex than simple overeating. For example, there is evidence suggesting that micronutrients such as vitamins and minerals may affect fat loss or gain. Poor sleep can affect your body's ability to control appetite, and obesity tends to be worse in areas with fewer sidewalks and bike paths.
To make a difference, any policy changes must be comprehensive, addressing the physical, economic, sociocultural and political environment.