Baby boomers, a group that constitutes a little more than a quarter of the U.S. population, started retiring last year -- in droves. Pew Research estimates that 10,000 boomers turn 65 each day, a phenomenon that won't end until sometime in 2030. This is good news for companies that specialize in elder care, a sector that includes real estate investment trusts like Health Care REIT (NYSE: HCN).

REITs that cater to boomers are booming
Health Care REIT has been scooping up companies that are geared toward the older crowd for some time now, just recently sealing a deal to purchase Sunrise Senior Living (NYSE: SRZ) for a cool $845 million. This company has been buying up properties left and right, making 22 acquisitions since early last year. Earlier this year, Ventas acquired Sunrise's stake in 16 senior communities. In both cases, Sunrise will continue to manage the properties.

These two companies, along with HCP, are the largest, but other senior living and health care REITs are also worth a look. Five Star Quality Care (NYSE: FVE) was once part of Senior Housing Properties Trust (NYSE: SNH), and was originally charged with operating properties reclaimed from the parent company's tenants. The company went public at the end of 2001, and now owns over 200 facilities nationwide.

Kindred Healthcare (NYSE: KND) operates 89 hospitals and 226 nursing and rehabilitation facilities throughout the country. Though not on par with the big three, this company has been growing through acquisitions, too. The Kentucky-based REIT announced very recently that it will be buying IntegraCare Holdings, which will increase its presence in Texas. Last October, the company acquired Synergy Home Health Care, which also provides home health services.

Fool's take
There's no doubt that the increasing number of elderly people will need the services these companies provide. Though Health Care REIT paid a premium for Sunrise Senior Living, it will be gaining communities that cater to wealthier clients in markets like New York and Los Angeles. The deal includes not only the 20 communities that Sunrise owns, but an interest in more than 100 other properties in which it has partial ownership in the U.S., Canada, and the U.K. When the deal closes by mid 2013, Health Care will own approximately 58,000 housing units.

Who knew that aging would become the new "growth" industry?

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