If you're a retiree, you have to strike an important balance with your retirement savings. Not only do you have short-term needs which require you to preserve capital and create income, but you also must continue to invest at least part of your portfolio with the long term in mind. After all, millions of retirees will live well into their 80s, and if you don't continue to grow -- or at least maintain -- some of your nest egg for those later years, you could be in for a pinch later in life. 

With those concerns in mind, we reached out to three of our top contributors, and asked them to discuss an ETF that makes sense for someone who's retired, or coming up on retirement, as a way to remain invested. They offered up three very different funds: one that's focused on dividend growth, one that's a great way to invest in real estate, and one that lets you take advantage of the long-term historic performance of growth stocks. 

Here's what they had to say. 

Low-cost, diversified income from real estate

Chuck Saletta: The Vanguard REIT ETF (NYSEMKT:VNQ) has a lot going for it when it comes to earning a position in a retiree's portfolio. As a real-estate-oriented investment, it can play a more income-oriented role than most traditional stocks, while still providing more growth potential than typical bonds. That makes it attractive for retirees who want current income while still trying to keep up with inflation over time.

In terms of that income, the Vanguard REIT ETF currently sports a respectable 4.3% yield. That yield is enabled by a low expense ratio: a minuscule 0.12%. The ETF aims to track the MSCI US REIT index, which includes property real estate investment trusts but excludes mortgage REITs. Mortgage REITs are generally viewed as high-risk ways to reach for yield, so being able to deliver that kind of yield without mortgage REIT risk just adds to the ETF's attractiveness.

In addition, the fund is fairly well diversified within the real estate space. With 150 different equities across healthcare, office, retail, industrial, and other sectors of the market, it provides one-stop diversification across industries -- or at least the land and buildings that those industries use. All investing involves risk, but the Vanguard REIT ETF's combination of low cost, decent yield, and reasonable diversification within the real estate sector make it worthy of consideration for a retiree's portfolio.

Even retirees need long-term growth

Jason Hall: Even retirees should invest a portion of their retirement portfolios for growth, and Vanguard Growth ETF (NYSEMKT:VUG) is an excellent low-cost ETF to serve that purpose. Why growth? Think about it this way: If you retire at 65, you're likely to live another 15 years if you're a man, and even longer if you're a woman. 

Why growth? At today's interest rates, even the best-yielding bonds won't provide for the kind of long-term growth to help sustain enough of your nest egg for later in life, and stocks are almost certainly going to have higher returns over the next 15 to 20 years than bonds or other interest-bearing instruments. And historically, high-quality growth stocks tend to outperform the stock market's average returns, so Vanguard Growth ETF is exactly the kind of ETF that makes sense for long-term investors, including retirees.

This is particularly true the longer you live. Investing a portion of your portfolio for the long term in a growth ETF like this one could make a big difference in your later years, whether it's providing for your care, or paying off that second yacht....

Why the Vanguard Growth ETF? In short, it has performed similar to the iShares Russell 1000 Growth Index ETF (NYSEMKT:IWF), yet is a lower-cost fund. The two funds aren't the same, as the Vanguard fund is based on a different growth index, but the performance is the key. I expect the Vanguard Growth ETF to perform at least as well -- and with a lower cost structure, you'll retain more of those returns. 

Dividend growth for long-term returns

Brian StoffelAs Jason has already pointed out, it's important to remember that you still need some growth to balance out the bonds and slow-growing stalwarts in your portfolio. I think many retirees can get just that by investing in the Vanguard Dividend Appreciation ETF (NYSEMKT:VIG).

The fund attempts to mimic the Nasdaq U.S. Dividend Achievers Select Index. That's a complicated way of saying that the fund invests in "U.S. common stocks that have a history of increasing dividends for at least ten consecutive years." The three largest holdings are Johnson & Johnson, Coca-Cola, and PepsiCo, but the ETF contains a total of 185 stocks.

Since inception, this fund has outperformed the S&P 500 by six percentage points -- earning 7.2% per year -- over a time frame that includes the Great Recession. That's a solid return for a retirement portfolio. Currently, it is offering up a 2.2% dividend yield.

When you consider that the expense ratio is an uber-low 0.10% of assets, you'll have a tough time finding a better ETF that features a balance of stalwarts and growing dividends.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.