Obesity
Being overweight puts your health at risk since it contributes to the development of many problems that include:
heart disease
high blood pressure
arthritis
diabetes
indigestion
gallstones
some cancers (for example, breast, colon)
snoring and sleep apnoea
stress, anxiety and depression
It's an equation of balance - if you eat more calories than you use in daily activity, the spare energy is stored as fat and weight increases. It's as simple as that.
Nowadays the average diet contains too many calories in the form of sugar and fat, and as a nation we've become more inactive. For example, many men spend their time sitting and watching sport when in the past they would have been actively taking part.
Jobs have become more sedentary too, with many men now sitting in front of a computer whereas in the past jobs would have been more physically demanding.