Is there an Obesity Epidemic?

In this section you will find articles and discussion regarding causes of obesity.  The phrase obesity epidemic has been thrown around a lot lately.  Is there an "Obesity Epidemic"?  And, if yes, who is responsible?  We need to find out first some common causes of obesity:

*Is it simply "calories in, calories out", or is there a greater problem?

*Is there too much emphasis on thinness that is driving our youth to a life of eating disorders?

*Is it because of air conditioning?

*Do large corporations or even the government have any responsibility for this grave issue?