Can you really accurately predict how well a stock will perform? Over the short run, the answer is "no" -- at least not consistently. However, investors can often accurately project with reasonable confidence how stocks in a given industry should fare over a longer time span. How? By looking at the macro trends impacting an industry.

Healthcare is definitely an industry that has important macro trends affecting its future. And many healthcare stocks are primed to benefit from these trends. 

Johnson & Johnson (JNJ 0.29%) reaches into multiple areas of healthcare. The company stands as one of healthcare's true giants, with a market cap of $274 billion. J&J markets prescription drugs, medical devices, and consumer products. 

Aetna (AET) is one of the biggest health insurers in the U.S. And it's about to become much larger with the pending acquisition of rival Humana. Aetna plays a leading role in the growing Medicare market.

Express Scripts Holding Company (ESRX) is the largest pharmacy benefits manager, or PBM, in the nation. As employers and payers seek to control increasing prescription drug costs, they turn to companies like Express Scripts. 

All three of these companies should reap rewards from major trends impacting healthcare. But what are these trends? Find out more below about these trends that offer incredible opportunities to smart investors.

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