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Many investors shy away from stocks after they retire. Yet even those in their 70s could easily need to stretch their money out over 20 years or more -- so you still need some of the growth potential that stocks provide. With that in mind, here are a few stocks that you can feel comfortable investing in even if your risk tolerance is low.

Give your portfolio some Wheaties
Consumer-staples stocks are some of the most-dependable investments that retirees can make, and Wheaties-maker General Mills (GIS -0.32%) is a great example of how companies with somewhat boring business models can still make money for their shareholders. The food stock has given long-term investors an average annual return of 12.5% during the past 30 years, and its performance recently has been just as impressive. A dividend yield of more than 3% also gives retirees the income they need.

General Mills has had to deal with the challenge of staying relevant in a space in which consumers want the healthiest options available. That's what was behind the cereal maker's purchase of organic specialist Annie's last year, which was a minor move for the food giant, but nevertheless gave it some valuable insight into an area of the market it had struggled with in the past. Moreover, by making the effort to cater to customers with moves like making Cheerios gluten free, General Mills is demonstrating the staying power it will need to serve investors for the long haul.

Let Home Depot be a solid foundation for your investments
The housing market has done well lately, and that's been a big boon for home-improvement retailer Home Depot (HD -0.31%). The company actually did a great job of surviving the downturn in housing, with strategic moves to shift its focus, and cater to the needs of its customers as they changed.

When millions were underwater on their mortgages, Home Depot focused on giving do-it-yourselfers the tools they needed to make the best of their existing homes through remodeling and renovation projects. Later, as conditions improved, Home Depot's two-part strategy of working both with do-it-yourselfers, and with professional contractors serving homeowners, sought to bite off an even bigger part of the industry.

Home Depot's returns have been stellar, with 15% annual average returns during the past decade, and even more impressive results over the longer run. A dividend yield of 2% won't turn that many heads, but with a solid track record, Home Depot is worth a closer look.

The Golden Arches are making a rebound
It's easy to mock McDonald's (MCD -0.42%) for the troubles it has gone through. With comparable-restaurant sales having suffered for a long period in recent years, the Golden Arches appeared ready to fall prey to heavy competition, both within the fast-food segment, as well as from fast-casual competitors offering higher-quality food items.

Recently, though, McDonald's has investors excited again, with its recent move to offer all-day breakfast, hoping to cater to a new crowd of potential customers. More importantly, McDonald's has started to simplify its menu, a decision that should help franchisees save money and allay some of their frustrations with the parent company. By refocusing on its domestic business, McDonald's hopes to restore the confidence that investors used to have in the stock. With 14% average annual returns during the past 30 years, and a current dividend exceeding 3%, McDonald's has a shot at giving risk-averse investors a nice combination of income and future growth.

Investors in their 70s won't want to take quite as many risks as they did when they were younger, but that doesn't mean you have to get out of the stock market entirely. By focusing on stocks that have risk levels that are more in line with your needs, you can make sure that you get the combination of dividend income, growth potential, and safety and security that you need in your investment portfolio.