What major factors changed the role of nutrition in Americans' overall health?

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I've done my homework. I'm willing to help you with yours, but you are going to have to show some initiative.

What factors do YOU think changed the role of nutrition?

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Hi I'm jeff I'm 26 and last night I was having rough sex with my wife and I pulled out and ejackulated on her back and noticed there was blood in my semen. Why is that.. help please