Obesity has increased a lot in the last thirty years in the United States. 30 years ago, no state had an obesity rate over 14 percent. Today, no state has an obesity rate under 20 percent. What caused the obesity rate to increase so much over the last three decades?
If you live in a city, you will see a lot of fast food stores. The number of fast food stores has increased a lot over the last thirty years. Mcdonalds and Burger King have started targeting international markets recently. Also, fast foods are also cheaper today than back in the days. Mcdonalds has a dollar menu and Burger King has a value menu. These stores are targeting the middle class more now than thirty years ago.
Televisions have a lot of advertisements. They tend to make people crave food even when they aren't hungry. Ads usually use attractive models or famous celebrities to convice the audience. Some commercials may have nothing to do with the food it serves. Others like Mcdonalds target children by giving away toys with meals.
The invention of the internet has made people lazy. Today, people stay on Facebook oy watch videos on Youtube. Thirty years ago, this wasn't possible. People had to find other ways to pass time and they ended up exercising more because of it. Our society has grown lazy over time and it has led to an increase in obesity rate.
Whether its an increase in the number of fast food stores, advertisements, or people staying home because if Facebook, people have gotten obese over time. There have been attempts to prevent obesity from increasing, but they haven't worked out. I think Obesity is an individual problem mostly because the person has the power to eat what they want and exercise when they want. Corporates might try to brainwash you, but you can't blame them for doing their job. At the end of the day, it is us, humans, who decide what we consume.
http://expertscolumn.com/content/obesity-rise

Comments
You've already mentioned the reason of an increase in obesity -fast food restaurants!
I know but its one of the main reasons for obesity.