Mushrooms may not be a fruit or a vegetable, but science says they are a boon to your health. You may already have a hunch that they pack a pretty nutritious punch: “They’re a good source of fiber, they also are low in calories, and they offer unsaturated fatty acids,” says registered dietitian Heather Bauer, founder of the nutrition subscription service Bestowed. But recent studies have shown that mushrooms have even more benefits than we previously realized.

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Not a fan of mushrooms? You may change your mind after we walk you through these fungi findings and the myriad of ways mushrooms boost your health:

Lose Weight
Researchers at Johns Hopkins University studied a group of adults who were trying to lose weight. Over the course of a year, half of these dieters substituted mushrooms for meat in their meals. The researchers found that these mushroom-eaters lost more weight than those on the meat diet, and they were able to keep this weight off.

Take-home tip:
At your next barbecue, try a grilled portabello instead of a burger on your bun. “Portabello burgers are a great hearty, healthy meal,” says Bauer. “You get that meaty, steak-y quality of a burger without the cholesterol.” She recommends brushing the portabellos with olive oil prior to grilling. But she warns against marinating your portabellos for too long, as they’ll over-saturate with oil.

Boost Your Immune System
Susan Percival, Ph.D., a professor of nutrition at the University of Florida, recently found evidence that mushrooms can benefit your immune system.She asked study subjects to eat shiitake mushrooms daily for four weeks. Percival took a blood sample from the participants before and after the experiment. After the four weeks of mushroom consumption, she found that their extracted immune cells were more reactive, with less inflammation, than before the experiment.

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“I have to say,” notes Percival, “that the changes before and after consumption of mushrooms was one of the clearest responses I’ve seen in all of my studies. Mushrooms seem to do an excellent job of supporting our immune system.”

While this study only considered shiitake mushrooms, Percival expects that future studies with other kinds of mushrooms will show similar effects. What’s more, other mushroom varieties, such as maitake, have even been shown to promote cancer-fighting cells.

Take-home tip: While Percival understands that it may be difficult for people to consume as many mushrooms as her study participants did, she recommends finding subtle ways to incorporate more of them into your diet, such as cutting them into small pieces and slipping them into a pasta sauce or soup.

Fight Fat
Further evidence of shiitake mushrooms’ benefits comes from research with rodents. In multiple studies, Australian and Chinese researchers found that rats on a high-fat diet accumulated less body fat when shiitake mushrooms were included in their meals.

Take-home tip: Try sautéing shiitake mushrooms. “That’s how you get the most flavor and nutrition out of them,” notes Bauer. Sauté them in a low sodium broth, and hold the salt while they’re cooking since it will dry out the mushrooms.

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Get in More Vitamin D
While many of us struggle to get enough vitamin D, mushrooms may provide as much of the sunny nutrient as vitamin supplements. An April 2013 Boston University study had people take daily vitamin D supplements or daily white button mushroom pills for three months over the winter. Those who took the mushroom pills showed similar vitamin D levels to the D-supplement takers at the end of the study.

Take-home tip: Slice and sprinkle mushrooms in salads and on your pizza. Or try Bauer’s favorite pizza recipe, which uses portabello mushrooms as the crust. “You take the stem off and put them bottom-up in the oven for about eight minutes,” she says. That takes the moisture out of them. Then you can add your own sauce and cheese, and bake them again until the cheese melts. Voila! Homemade mushroom pizza.

How to Pick and Prep Mushrooms
“When shopping for mushrooms,” Bauer says, “you always want to pick ones that are firm and dry. Make sure they’re not slimy.” For storing mushrooms, steer clear of plastic wrap, which will make them go bad faster. Instead, Bauer recommends storing mushrooms in a paper bag in the refrigerator or on a plate with paper towels on both sides. “Either way,” she adds, “they have to be used in four days or they’ll spoil.”When preparing to cook your mushrooms, small, smooth mushrooms like white buttons can simply be wiped off with a paper towel, notes Bauer, but heftier mushrooms like portobellos need to be rinsed in the sink.

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