People eat junk food knowing it is bad for their health for the same reason why so many people abuse alcohol, drugs, and cigarettes. Junk food is addicting due to the many known and unknown preservatives, chemicals, sugar, high fructose corn syrup, and many other things that have been proven time and again to be addictive.
The government states that smoking is the leading cause of preventable death and illness among Americans. I disagree. I believe obesity is the leading cause of preventable death and illness among Americans. There is just simply too much money to be made through the food industry and pharmaceutical industry to change this growing epidemic though.
People know junk food is unhealthy but are unable to stop because they are addicted. Their bodies need for calories increase because of the empty calories they invest from junk food. The more empty calories you take in the more your brain triggers cravings to eat more calories hoping that you will eventually get some vitamins and minerals in there somewhere.
People eat junk food because they are addicted and cant help themselves and the industry knows this and keeps bombarding us with cheaper, faster, better tasting junk to keep us addicted.
It is unfortunate and a huge problem that doesn’t seem to be getting better anytime soon.