We know: Sometimes it's painful to spend your hard-earned cash on organic, grassfed beef—especially when it costs up to six times more than conventional meat. But the organic stuff is healthier for you (it has more omega-3s!) and better for the earth (adios, synthetic pesticides and fertilizers!). And now, a new Consumer Reports investigation reveals yet another benefit: Organic, grassfed beef is significantly less contaminated with harmful bacteria than the conventional stuff.

Consumer Reports editors purchased 300 ground beef samples from across the country, some conventional and some "more sustainably produced" (an umbrella term for beef with labels like "organic," "grass-fed," or "raised without antibiotics").

They tested each sample for common, food-poisoning-provoking bacteria, like E. coli and Salmonella. Then they tested these strains of bacteria for resistance to common antibiotics. The results were pretty sobering (and pretty gross): Compared to the sustainable options, conventional beef was more likely to be contaminated with bacteria overall—and it was twice as likely to be contaminated with strains of bacteria that are resistant to common antibiotics. Even MRSA, the superbug that kills about 11,000 Americans every year, showed up. It was found on three of the conventional samples, but none of the sustainable ones.

MORE: 5 Things You Need to Know Before Buying Grass-Fed

Before you freak out, take a deep breath: Bacteria on raw meat isn't always a cause for alarm. After all, the testers found at least some type of potentially harmful bacteria on all of the samples—and if you cook meat to the right temperature, you'll easily vanquish the bugs.

But Consumer Reports says that ground beef poses a unique risk compared to other cuts of meat. In whole cuts like steak, bacteria tend to stay on the surface, where we typically sear meat at high temperatures. But in ground beef, bacteria are mixed throughout—that means they'll probably survive at the cool, pink center of a rare hamburger. Finally, most ground beef you buy at the store comes from multiple animals, and one contaminated animal can be distributed in many packages of finished product. Given all this, it's not too surprising that there were nearly 80 recalls of contaminated beef between 2003 and 2012—or that tainted beef alone is responsible for a about 50% of E. coli infections in the U.S. annually.

MORE: Mark Bittman: Five Ways to Make Red Meat Healthy

Now for some good news: You don't have to swear off ground beef completely in order to stay safe. You just have to make smarter choices. The report suggests that all consumers stick to the following guidelines:

1. Eat less beef.
Buying less beef overall means that splurging on higher-quality varieties won't hit your wallet quite as hard.   

2. Know your labels.
Package claims like "humanely raised," "environmentally friendly," or "natural," are totally meaningless. Instead, look for verified seals that denote cows were grass-fed and not treated with unnecessary antibiotics. Some of the most trustworthy and meaningful: USDA Organic, PCO Certified 100 percent Grassfed, Animal Welfare Approved Grassfed, and Demeter Biodynamic.

3. Handle and cook beef properly.
Swing by the meat section of the grocery store at the very end of your shopping trip (rather than the beginning), and keep meat below 40°F until you cook it. Wash your hands after touching raw meat, and cook ground beef to a temperature of 160°F (measured with a meat thermometer) before serving.