Do you like buying low and selling high? If you answered "no," you can return to watching Jersey Shore reruns in your Snuggie. If you answered "yes," then it may be time to take a look at health-care stocks. Finding out-of-favor industries and unloved stocks is a key ingredient to cooking up some nice returns, and few industries have received more scorn lately than health care. Instead of trying to pick out a few key companies, when an entire sector is this much out of favor, a broad ETF may serve your needs better.

So how bad has it been for pharma, biotech, and health-care investors? Ugly. Really ugly. After a period of great returns in the 1990s, seemingly the only times health-care stocks outperformed in the last 10 years was when the broader market was down. Even as the market rebounded in 2010, the health care sector was only up 3%. If you want out of favor, it doesn't get much out of favor than this.

So the kindest way to describe health-care investments is "defensive," but that doesn't mean you can't earn nice returns in certain corners of the sector. Let's look at several ETFs that can fill both needs.

For investors looking to get defensive or anticipating a trend reversal, iShares S&P Global Healthcare (NYSE: IXJ) could do the trick. It mainly focuses on the largest health-care players, but because of its global nature, I would recommend it over iShares Dow Jones US Pharmaceuticals (NYSE: IHE). The U.S. pharma ETF's hyper-concentrated exposure to a select handful of U.S. based pharmaceuticals leaves investors vulnerable to both country and company risk, with more than a quarter of its assets in Johnson & Johnson, Pfizer (NYSE: PFE), and Merck (NYSE: MRK) alone! At that point you would be better off investing directly in your favorite member of Big Pharma, whether you like Merck and its renewed commitment to R&D or Pfizer and its focus on returning capital to shareholders via buybacks and dividends.

One space where it is tougher to pick a favorite is in the rough and tumble world of biotech. Here, binary outcomes, whether a drug successfully passes each checkpoint on the road to approval, and takeovers have dramatic effects on share prices. If you don't have time to wade through clinical trial data, it may be advantageous to fish with the wide net that an ETF like PowerShares Dynamic Biotech & Genome (NYSE: PBE) offers. Large players like Amgen and Biogen are represented well, but several of its top 10 holdings are companies with market caps under $10 billion. The ETF has performed remarkably well, offering investors 30% returns over the last two years, and even a healthy 4.5% per year gain for those who invested four years ago, before the financial crisis hit.

And for those who really want to venture into the wild west of small-cap pharma, may I suggest SPDR S&P Pharmaceuticals (NYSE: XPH). Unlike the previous fund, the SPDR ETF is filled with less proven players, so expect to see plenty of volatility from the fund's top holdings. For instance, Vivus (Nasdaq: VVUS) recently suffered a large setback when its obesity drug Qnexa ran into FDA concerns over side effects. However, the returns here match the higher degree of risk, as this small ETF has delivered total returns of 80% since early 2009.

No matter which way you go, there are ETFs that can accomplish a variety of investment goals within the health-care sector. If you have any favorites that I missed, shout them out in the comments below.