It's a largely U.S. problem, same with many other disorders. The industrial era has put so many carcinogens into the air, water, and food that there is bound to

It's a largely U.S. problem, same with many other disorders. The industrial era has put so many carcinogens into the air, water, and food that there is bound to be changes. Combine this with American culture of being unhealthy, and now families are started far later in life - it's a "no duh" situation.