Marijuana stocks were among last year's top performers, but that doesn't guarantee that they'll be top stocks this year, too. Although the allure of marijuana's potential from legalization may be enticing, investors could discover that these three investments make more sense -- and come with less risk.

Source: Bristol-Myers Squibb

Todd Campbell: It's often been proven that chasing the latest investing fad can be perilous, so while marijuana's potential is intriguing, investors may be better served focusing on great companies, in proven markets, that offer a much clearer opportunity for upside.

For example, cancer treatment is a big and growing market that offers plenty of shareholder-friendly growth. There have been substantial strides in cancer treatment since President Nixon declared war on cancer in 1971, but it's only recently that innovation, such as the mapping of genes, has unlocked secrets that could revolutionize treatment.

Some of the most interesting cancer research is happening at big drug companies like Bristol-Myers Squibb (NYSE:BMY). In December, the FDA approved Bristol-Myers Opdivo, a melanoma drug that blocks a key mechanism (PD-1) used by cancer cells to sidestep the immune system. Opdivo's potential is so big that industry analysts think its peak sales could eclipse $7 billion by 2020.But Bristol-Myers isn't alone in conducting cutting-edge cancer research. For example, BioMarin Pharmaceuticals (NASDAQ:BMRN) is working on a drug that may offer hope to cancer patients with a specific gene mutation. Since IMS Health projects that spending on cancer medicine will climb to nearly $100 billion annually by 2020, investors may find that cancer drug investments like these are a better bet than marijuana.

Source: Blu.

Selena Maranjian: There's long been great debate about whether smoking tobacco or marijuana is worse (or better!) for your health, with many studies, perhaps surprisingly, finding that marijuana might be preferable to tobacco. When it comes to investing, though, consider plunking your hard-earned money into tobacco stocks, not marijuana ones. Some marijuana stocks might perform well over the long term, but at this point, there's more speculation than long track records of solid performance. After all, it's not entirely clear whether or when there will be widespread national recreational use of marijuana, or whether medicinal use approval will grow or falter.

Meanwhile, for smoking and non-smoking investors alike, there are tobacco stocks that happen to have been outstanding performers for decades, thanks in part to the fact that they offer a product that is literally addictive. Altria Group (NYSE:MO), for example, which sells the Marlboro brand domestically, among other endeavors, has averaged an annual return of 20.7% over the past 30 years (and more than that over the past five), and recently yielded a solid 3.9%. Philip Morris International (NYSE:PM), its international counterpart, recently yielded 4.8% and has averaged 16.5% over the past five years. Lorillard (UNKNOWN:LO.DL), which is merging with Reynolds American (NYSE:RAI), has averaged 27.2% over the past five years, and yields about 3.8%.

These aren't slam-dunk long-term investments, though, because they do face some significant challenges, such as a shrinking smoking base domestically, rising taxes on tobacco (often partially aimed at reducing the smoking rate), increased regulations against smoking, and public health campaigns against tobacco use. Still, they're far from dead yet, they generate hefty free cash flow, and they have been responding to threats with some innovation, such as electronic cigarettes, and diversification. (Altria, for example, has a 27% stake in SABMiller (NASDAQOTH: SBMRY), a major beer and soft drink company.) If you want to add smoke to your portfolio, think tobacco. 

Dan CaplingerInvestors have celebrated the legalization of marijuana in states like Colorado and Washington, but they've ignored the potential risk that harsher enforcement of existing federal law prohibiting marijuana could crush emerging businesses in the industry. For my money, I'd prefer sin stocks that have already gone through the legislative wringer, and that points me to alcohol and its Prohibition-busting staying power over the decades.

Many argue that alcohol is potentially more destructive than marijuana, but from an investing standpoint, alcohol stocks have done quite well and appear poised to benefit from favorable trends both in the U.S. and around the world. Beer giants Anheuser-Busch InBev (NYSEMKT: BUD) and Constellation Brands (NYSE:STZ) have seen their stocks soar in recent years, with Constellation in particular benefiting from huge growth after its 2013 acquisition of the U.S. rights to market Grupo Modelo beer brands like Corona and Tsingtao. Elsewhere in the industry, spirits manufacturers have seen a spike in interest beyond the beer and wine segment, with innovations like flavored vodka sparking demand from a new generation of consumers.

No matter what happens to marijuana, you can count on sellers of beer, wine, and spirits having lasting demand from a thirsty customer base for decades to come.