In the midst of a brutal market sell-off, it's tough for investors to think about anything other than the misery of the moment. Folks are more concerned about what's going to be happening five minutes from now than where stocks will be five years from now, which is understandable.

It's also a mistake, however. While difficult to imagine given our current circumstances, the current pullback is ultimately a buying opportunity...even if we haven't yet seen the ultimate bottom. You just have to keep the long term in mind.

With that as the backdrop, here's a rundown of three investments that may look like they're in trouble now, but should pay off big-time for anyone willing to give them the kind of runway they deserve.

McDonald's

You may think of McDonald's (MCD 0.33%) as a fast-food restaurant chain. That's not a completely on-target categorization, though. To those who know it well, the company is often described as a real estate company that just so happens to rent exclusively to restaurant franchisees looking to plug into the powerful brand name.

It's unlike any other fast-food chain. Whereas operators of rival restaurants like Wendy's or Arby's typically own their own land and the building on it, McDonald's franchisees don't. Rather, as part of their franchise agreement, McDonald's operators agree to rent their stores from the parent company. That's a cost in addition to other royalties and franchise fees typical of the business.

A couple reviewing their stock portfolio.

Image source: Getty Images.

Here's the catch for franchisees, and the upside for McDonald's shareholders: Unlike a mortgage payment on purchased real estate, rents charged to McDonald's "tenants" are adjusted to reflect the market-based rate for that property...in perpetuity. The franchiser -- McDonald's -- is guaranteed not just recurring cash flow, but ever-increasing cash flow. Franchisees don't mind the arrangement, however, since they still tend to earn more running a McDonald's store than they would with any other fast-food outfit.

This corporate franchiser/franchisee structure is particularly well-suited for funding dividends, which McDonald's has increased every year for the past 45 years.

Pinterest

To say Pinterest (PINS 1.22%) has been a tough name to own of late would be a considerable understatement. It's been downright gut-wrenching to hang on to, having fallen on the order of 80% over the course of the past year.

The sell-off is largely the result of user losses. As the pandemic's impact has eased, many of those people who became involved with the social media site stopped using it again in favor of doing more things in the real world.

We're nearing a turning point for the company's user base, though. Now roughly a year removed from the beginning of its attrition, don't be surprised to see user losses start to contract, or even see new user growth as Pinterest's pre-pandemic growth initiatives start to work again in a more normal environment. These initiatives include more financial incentives for content creators and brands, in addition to a more refined and effective advertising platform.

The encouraging irony is, despite fewer regular users, the company has continued to see fiscal growth. Revenue improved by 52% in fiscal 2021, nearly tripling last year's earnings before interest, taxes, depreciation, and amortization (EBITDA), and pulling the company out of the red and into the black on an operating basis. This year won't be quite as heroic, but with several initiatives continuing to gain traction, the analyst community is still calling for sales growth of 20% this year before accelerating nearly 26% next year.

The market should connect the dots sooner or later.

DexCom

Finally, add DexCom (DXCM -0.50%) to your list of surefire investments you'll thank yourself for later.

If you're not familiar with the company, it's pretty simple. DexCom makes continuous glucose monitoring systems (or CGMs) to help people with type 2 diabetes manage their condition. Its tech accounts for roughly 40% of the market, although this leading share hasn't helped the stock much of late.

What's not currently reflected in DexCom stock's price, however, is how immature the continuous glucose monitoring market still is. As this sliver of the healthcare technology industry moves away from older solutions -- including finger pricks -- and toward CGMs, DexCom stands to experience tremendous growth.

Market research outfit Technavio puts the idea in perspective, estimating the highly fragmented glucose monitoring wearable market will grow at an average of 12% per year through 2024, with the CGMs this company makes being one of the industry's key growth drivers. The North American market -- where DexCom does about three-fourths of its business -- is projected to lead the rest of the world on this front. And, for better or worse, the fact that American diets continue to worsen and drive up the incidence rates for type 2 diabetes only means these growth estimates could be too conservative.

One thing's for sure either way -- this year's projected revenue growth of 19% is neither a fluke nor unusual. Next year's growth pace should be even stronger, extending a more than decade-long streak of uninterrupted quarterly sales improvements.