1 million people of 100 years of age or more by 2050

It is presently expected that over 1 million people just in the U.S. alone will be over 100 by 2050. Why is this?

Education. Diet. Exercise. choosing longevity. Spiritual practices. People becoming less self destructive than before. Consciously teaching each other how to live longer and longer which I believe the first people will attain 150 to 200 years of age somewhere on earth publicly this century by 2100.