Recessions, or prolonged economic downturns, are a part of economic life that can not be avoided. That's important for investors to keep in mind as they pick stocks, because the best way to deal with these cyclical events is to pick companies that can survive through them. Three real estate investment trusts (REITs) you'll want to examine on that score are Realty Income (O 0.26%), W.P. Carey (WPC 0.53%), and National Retail Properties (NNN 0.53%). Here's why.

The proof is in the dividends

Recessions happen and will likely always happen because of human nature's unfortunate history of taking things to extremes. Downturns can be thought of as a way to clean up after a bout of unjustified euphoria. But here's the thing -- there have been three recessions since 1998. One was so bad it was named the Great Recession. REIT W.P. Carey held its initial public offering in 1998 and, despite those economic downturns, it has increased its dividend every year since. That puts it on the cusp of 25 years, which is Dividend Aristocrat land.

The dividend streaks at Realty Income and National Realty are even more impressive, at 27 years and 32 years, respectively. These landlords have faced the storm of recession and not only lived to fight another day, but continued to reward investors right through the downturn. That's the type of perseverance that you should be looking for when trying to recession-proof your portfolio.

2. Keep it simple

Although each of these REITs takes a slightly different approach, the one unifying feature is that they all use net leases. That means that their tenants are responsible for most of the operating costs of the properties they occupy. It's pretty low risk when spread across a large portfolio. Realty Income owns over 11,000 properties, W.P. Carey 1,300, and National Retail 3,200. W.P. Carey's tally may seem low, but that's related to the types of properties it owns, which tend to be larger (more on this below).

One of the key factors in net lease deals is that they tend to involve long-term leases. The average lease length for all three of these REITs exceeds 10 years, which should easily be long enough to outlast a recession. Basically, this trio owns lots of low-maintenance assets backed by very long leases (many of which include annual rent increases), which is exactly what you'll want to survive an economic downturn.

3. Three ways to play

That said, there are big differences here. National Retail Properties is the most focused, owning single-tenant retail assets in the U.S. that are largely necessity based. This is all it does and all it wants to do. Realty Income generates around 80% of its rents from retail assets, but has some industrial assets mixed in too. Where it stands out is its massive size, highlighted by the portfolio metrics from above. It is so big that it can take on deals that its peers wouldn't be able to handle. W.P. Carey, meanwhile, has the smallest portfolio but is easily the most diversified, with often larger individual assets spread across the industrial, warehouse, office, retail, and self storage areas. It also generates a material amount of rent from Europe, allowing it to put money to work in just about any market environment. 

Which approach appeals most to you will be unique to you, of course, but all three have their merits. Realty Income's size and investment-grade balance sheet, for example, suggests it can weather just about any storm. National Retail Properties' focus on necessity assets and strong partnerships gives it the wherewithal to muddle through downturns and come out stronger on the other side. And W.P. Carey tends to shift its investments to take advantage of the best opportunities, which often pop up during difficult economic periods.

Focus on the income

When times get tough, it often pays to focus your attention on things other than stock prices. So when the next recession hits, you can focus on Realty Income's 4.3% dividend yield, W.P. Carey's 5%, or National Retail's 5.1% to distract you from short-term stock price volatility. And, given the regular dividend increases all three of these REITs have provided over time, it's likely you'll even get some good dividend growth news during the next recession to lift your spirits during dark economic days.