You know mushrooms as an ingredient in a salad or as a topper for a pizza, but traditional Chinese medicine recognized the health and medical benefits of mushrooms centuries ago. Chefs like to add them to higher-end culinary creations too. Despite being 90% water, the other 10% of the mushroom is packed with vitamins, minerals, and nutrients. Therefore, mushrooms are an excellent addition to your diet, but what kind should you choose? Do some mushrooms have more health benefits than others?
The Nutritional Breakdown of Mushrooms
Studies show that mushrooms contain compounds with antioxidant and anti-inflammatory activity. One antioxidant in mushrooms is selenium, a trace mineral that also plays a key role in thyroid function. Selenium supports the body’s natural antioxidant defense system. However, you don’t want to take a selenium supplement since high doses of selenium can be toxic. Therefore, foods like mushrooms are a good way to get this trace mineral that your body needs in small quantities. But mushrooms are also a good source of other micronutrients. When you expose mushrooms to ultraviolet light from the sun, they produce vitamin D. Mushrooms also contain fiber, vitamin C, potassium, and a variety of B vitamins. In addition, mushrooms are low in calories and carbohydrates and are around 20 to 30% protein by weight.
Are All Mushrooms Created Equal?
With so many varieties of mushrooms available, you might wonder which to choose. All cultivated mushrooms have nutritional benefits and probable health benefits, but some types, based on small studies, have distinct health effects that set them apart from other mushrooms. Let’s look at some types of mushrooms you find at supermarkets and what science says about them.
White Button Mushrooms
Button Mushrooms are an inexpensive variety of mushrooms you find at most supermarkets, but don’t let their inexpensive price and easy availability fool you! Button mushrooms have more potassium than other types of mushrooms with around 300 milligrams per serving, almost as much as a medium banana.
Studies show that white button mushrooms suppress aromatase, the enzyme that converts testosterone to estrogen. Fat cells produce estrogen from androgens and this increases the amount of circulating estrogen in the body. That’s important since estrogen stimulates the growth of breast tissue, including the growth of abnormal breast cells. Eating foods high in aromatase reduce the impact of estrogen on breast tissue and may lower the risk of developing estrogen-sensitive breast cancer. In fact, some breast cancer survivors take a prescription aromatase inhibitor to reduce breast cancer recurrence. Eating white button mushrooms provides a weak source of aromatase that may help lower breast cancer risk. Studies link diets high in mushrooms with a lower risk of breast cancer, but it’s not clear whether the reduction is because of the mushrooms alone or is because of synergy with other foods.
Maitake Mushrooms
Maitake mushrooms are more expensive and harder to find than the common button mushroom but tracking them down might be worth the effort. Research shows that they may help with blood sugar control. In fact, scientists found that diabetic rats that consumed maitake mushroom extract experienced a drop in blood glucose and a reduction in systolic blood pressure relative to diabetic rats that didn’t. Therefore, maitake mushrooms may be beneficial for people with diabetes.
If you take medications for blood sugar control, talk to your physician before eating lots maitake mushrooms since the combination of glucose-lowering medications and maitake could drop your blood sugar too low. Other research suggests that maitake mushrooms boost the immune response and help lower cholesterol, although we need more human studies to draw firm conclusions.
Shiitake Mushrooms
Shiitake mushrooms are also more expensive mushroom than the common button mushroom, but they’re available in many grocery stores these days. Along with having more fiber than white button mushrooms, shiitake contains polysaccharides that activate the immune response against pathogens, like viruses and bacteria. How do we know this?
In one study, participants who ate 4 ounces of shiitake mushrooms daily for 4 weeks had an increase in gamma delta T-cells, an immune cell that fights viruses. As a bonus health benefit, the participants also enjoyed a reduction in inflammatory activity. Therefore, shiitake mushrooms may help optimize immune activity. You want your immune system to fight viruses and other invaders but not go overboard and attack normal tissues. In addition, shiitakes contain a compound that fights tumor growth called lentinan.
Oyster Mushrooms
Oyster mushrooms may have unique cholesterol-lowering properties because they contain compounds also in the cholesterol-lowering medication called lovastatin, a type of statin medication. This sets them apart from other common mushrooms, although they’re similar to other mushrooms in terms of their nutritional profile.
Porcini Mushrooms
Porcini mushrooms also have anti-inflammatory activity. A study in mice found that those who consumed porcini mushroom extract had reduced markers of inflammation and developed less airway inflammation when researchers exposed them to a substance that triggered asthma. Porcini’s are similar in texture to Portabello mushrooms. That’s why people sometimes use them as a substitute for meat. Plus, they’re a good source of antioxidants, including vitamin C, lycopene, and beta-carotene.
A Word of Caution
Buy your mushrooms from a reputable grocery store and avoid gathering mushrooms from outdoors. Unless you’re a seasoned expert, it’s hard to distinguish a safe mushroom from a poisonous one. Each year, people die from eating wild mushrooms that they gathered and wrongly identified as safe. Also, cook mushrooms before eating them. Why? Raw mushrooms contain small amounts of chemicals called hydrazines that are a possible carcinogen, but cooking inactivates them. You’d have to eat a lot of raw mushrooms to have ill effects, but why take the chance when you can enjoy them sautéed, roasted, grilled, or in a soup or stew?
Mushrooms are as versatile as they are delicious. So, prepare a variety of mushrooms and add them to soups, stews, wraps, sandwiches, and in your next pasta recipe. A portobello mushroom can be a substitute for a burger on a bun, and they taste delicious hot off the grill. So, experiment and discover your own favorite ways to enjoy mushrooms. You’ll soon wonder how you lived without them!
References:
- Medical News Today. “What is the nutritional value of mushrooms?”
- Cancer Res. 2006 Dec 15;66(24):12026-34.
- com. “White button mushroom extract has mild influence on aromatase activity”
- com. “Maitake Mushroom”
- Science Daily. “Mushrooms boost immunity, suggests research”
- Mymensingh Med J. 2007 Jan;16(1):94-9.
- Am J Transl Res. 2016; 8(10): 4478–4489.
- J Food Sci Technol. 2015 Dec; 52(12): 7944–7953.
