Does stock market volatility have you worried? Following the worst single-day performance for the Dow Jones Industrial Average and S&P 500 since the November election, and quite a big rally in all three major U.S. indexes over the past five months, we may start witnessing a flight to safe stocks. 

Safe stocks help us sleep at night, and they seemingly have business models that could thrive in any economic environment. 

With that said, we asked three of our Foolish contributors to name safe stocks they believe risk-averse investors should consider buying right now. Making the list were grocer Kroger (KR 0.94%), software giant Adobe Systems (ADBE 0.89%), and biotech blue chip Celgene (CELG).

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Ya gotta eat

Brian Feroldi (Kroger): Grocery stores are a recession-proof industry since no one stops eating during a downturn. The trouble with investing in the sector is that the industry is brutally competitive, so picking winners can be difficult. However, industry giant Kroger has proven that it is more than capable of holding its own, which makes this an extremely safe holding.

The funny thing about Kroger is that you might be one of the company's customers and not even know it. That's because Kroger has been gobbling up regional chains for years. Ever shopped at a Roundy's, Harris Teeter, Fred Meyer, Ralph's, Murray's Cheese, or King Soopers? Those are all chains owned by Kroger.

One way that Kroger maintains an advantage over rivals is by using its huge scale and buying power to keep its costs low. The company is also laser-focused on providing a nice shopping experience for it customers that helps to differentiate it from price-focused rivals. When adding in the company's big push into the organics space, Kroger has had no problems keeping its customers loyal. In fact, the company has gained market share in the industry for 12 consecutive years. That's an impressive accomplishment.

Between organic growth and acquisitions, Kroger's top line has steadily marched higher over the last decade. The company also has a habit of using excess cash to repurchase shares. The combination has allowed Kroger's earnings per share to grow faster than its revenue.

KR Revenue (TTM) Chart

KR Revenue (TTM) data by YCharts.

I think investors can expect this trend to continue. Meanwhile, shares are trading for only 14 times trailing earnings. Mix in a steadily growing dividend that currently yields 1.7% and I think Kroger is a terrific choice for any investor who prizes safety above all else.

All part of the plan

Tim Brugger (Adobe Systems): With its stock price up 22% this year -- and 35% over the past 12 months -- Adobe may not seem like the safest of bets right now. However, the reason Adobe shareholders are enjoying such a nice run of late is why it's one of the safest stocks you can buy now.

CEO Shantanu Narayen started a committed effort a couple of years ago to change Adobe's revenue-generation model from one reliant on new, one-time software sales to one focused on subscriptions. The change wasn't received with open arms, and many pundits and customers were less than enamored with the switch to a cloud-driven, annual recurring revenue (ARR) sales approach. They were wrong.

A businessman demonstrating the reach of cloud computing.

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Last quarter, Adobe's subscription sales climbed 29% year-over-year to $1.38 billion, and accounted for 82% of its record-breaking $1.68 billion in revenue in fiscal 2017's first quarter. Adobe's skyrocketing ARR is the basis for it being one of the safest stocks around because it translates to a reliable, and relatively predictable, revenue foundation rather than relying solely on new sales.

Not only does ARR result in consistent, albeit slower, revenue growth, it simply costs less to service existing customers than driving new sales. Last quarter was yet another example of that. Adobe's operating expenses increased 11% in the first quarter, though revenue jumped 22%. For risk-adverse investors, ongoing revenue growth double that of expense increases translates to few, if any, quarterly earnings surprises. Which is why Adobe is one of the safest stocks to buy right now.

Safety is a matter of context

Sean Williams (Celgene): When most investors think of "safe stocks," they probably have stalwarts like Coca-Cola or Philip Morris International in mind. Me? I'd point you toward a high-growth biotech megacap named Celgene.

Why on earth would you want to invest in Celgene? To begin with, its lead drug, Revlimid, is a beast in treating multiple myeloma. It's one of the most prescribed cancer drugs in the world, with sales totaling $6.97 billion in 2016, a 20% increase from the prior year. 2017 estimates from the company call for $8 billion to $8.3 billion in sales, with Revlimid likely making a run at $10 billion in annual sales before the decade is over. Working in its favor are an increasing number of multiple myeloma diagnoses, new combination therapies that include Revlimid, exceptional pricing power, and a longer duration of use.

Lab researcher using pipettes and test tubes.

Image source: Getty Images.

But, even more importantly, Celgene worked out a deal in December 2015 with generic-drug makers that'll keep the flood of generic Revlimid off the market until January 2026. Beginning in March 2022, a small amount of generic Revlimid can be sold, but this deal essentially set Revlimid up to be a multibillion-dollar cash cow for Celgene for at least the next decade.

Celgene's pipeline and product portfolio are also growing through three separate channels. First, there's organic label expansion opportunities, by which I mean Revlimid and Otezla. The company's oral anti-inflammatory drugs are being studied in new indications that could boost their sales. Secondly, there are acquisition opportunities, such as Celgene's $7.2 billion acquisition of Receptos in mid-2015 to get hold of experimental next-gen multiple sclerosis and ulcerative colitis drug ozanimod. Lastly, there are Celgene's dozens of partnership opportunities. These partners have been promised a small fortune in milestone payments for clinical success, but they put Celgene in the driver's seat to license first-in-class oncology, immunology, and anti-inflammatory therapies.

Celgene is a veritable growth machine that's a long ways away from being challenged by generic competition. That makes this high-growth biotech stock arguably one of the market's safest bets.