Obesity and fast food

Cheap, fattening foods are just hard to resist.

A review of several studies finds obese adults have a bigger brain response to sweet and fatty foods.

Researchers say this makes obese adults more sensitive to high-calorie meals, many of which are heavily advertised, and easily accessible.

They say it is easy to see how obesity levels are on the rise when these vulnerabilities in the brain are combined with an unhealthy environment.