Mushrooms, though classified as vegetables in the food world, are not technically plants. They belong to the fungi kingdom and although they are not vegetables, mushrooms provide several important nutrients.
It's common knowledge that the key to getting enough vitamins and minerals in the diet is to eat a colorful variety of fruits and vegetables - the more color, the better. However, this philosophy tends to leave mushrooms in the dark. In many cases, if a food lacks color, it also in turn lacks necessary nutrients. However, mushrooms - which are commonly white - prove quite the contrary.
This MNT Knowledge Center feature is part of a collection of articles on the health benefits of popular foods. It provides a nutritional breakdown of mushrooms and an in-depth look at their possible health benefits, how to incorporate more mushrooms into your diet and any potential health risks associated with their consumption.
Nutritional breakdown of mushrooms
Mushrooms are naturally low in sodium, fat, cholesterol, and calories and have often been referred to as "functional foods." In addition to providing basic nutrition, they help prevent chronic disease due to the presence of antioxidants and beneficial dietary fibers such as chitin and beta-glucans.
Mushrooms, though classified as vegetables in the food world, are not technically plants. They belong to the fungi kingdom.
One cup of chopped or sliced raw white mushrooms contains 15 calories, 0 grams of fat, 2.2 grams of protein, 2.3 grams of carbohydrate (including 0.7 grams of fiber and 1.4 grams of sugar). Although there are a large variety of mushrooms available, most provide the same amount of the same nutrients per serving, regardless of their shape or size.
Mushrooms are rich in B vitamins such as riboflavin, folate, thiamine, pantothenic acid, and niacin. They are also the only vegan, non-fortified dietary source of vitamin D. Mushrooms also provide several minerals that may be difficult to obtain in the diet, such as selenium, potassium, copper, iron, and phosphorus.1
Beta-glucans are a type of fiber that is found in the cell walls of many types of mushrooms. Recently, beta-glucans have been the subject of extensive studies that have examined their role in improving insulin resistance and blood cholesterol levels, lowering the risk of obesity and providing an immunity boost.3
Mushrooms also contain choline; an important nutrient found that helps with sleep, muscle movement, learning and memory. Choline assists in maintaining the structure of cellular membranes, aids in the transmission of nerve impulses, supports proper fat absorption and reduces chronic inflammation.7
Possible health benefits of consuming mushrooms
Consuming fruits and vegetables of all kinds has long been associated with a reduced risk of many lifestyle-related health conditions. Countless studies have suggested that increasing consumption of naturally-grown foods like mushrooms decreases the risk of obesity and overall mortality, diabetes, heart disease and promotes a healthy complexion and hair, increased energy, and overall lower weight.
Cancer: Mushrooms contain just as high an antioxidant capacity as carrots, tomatoes, green and red peppers, pumpkins, green beans, and zucchini.4
Selenium is a mineral that is not present in most fruits and vegetables but can be found in mushrooms. It plays a role in liver enzyme function, and helps detoxify some cancer-causing compounds in the body. Additionally, selenium prevents inflammation and also decreases tumor growth rates.2
The vitamin D in mushrooms has also been shown to inhibit the growth of cancer cells by contributing to the regulation of the cell growth cycle. The folate in mushrooms plays an important role in DNA synthesis and repair, thus preventing the formation of cancer cells from mutations in the DNA.2
Diabetes: Studies have shown that type 1 diabetics who consume high-fiber diets have lower blood glucose levels and type 2 diabetics may have improved blood sugar, lipids and insulin levels. One cup of grilled portabella mushrooms and one cup of stir-fried shiitake mushrooms both provide about 3 grams of fiber.
The Dietary Guidelines for Americans recommends 21-25 g/day for women and 30-38 g/day for men.
Heart health: The fiber, potassium and vitamin C content in mushrooms all contribute to cardiovascular health. Potassium and sodium work together in the body to help regulate blood pressure. Consuming mushrooms, which are high in potassium and low in sodium helps to lower blood pressure and decrease the risk of high blood pressure and cardiovascular diseases.
Additionally, an intake of 3 grams of beta-glucans per day can lower blood cholesterol levels by 5%.3
Immunity: Selenium has also been found to improve immune response to infection by stimulating production of killer T-cells. The beta-glucan fibers found in the cell walls of mushrooms stimulate the immune system to fight cancer cells and prevent tumors from forming.3
Weight management and satiety: Dietary fiber plays an important role in weight management by functioning as a "bulking agent" in the digestive system. Mushrooms contain two types of dietary fibers in their cell walls: beta-glucans and chitin which increase satiety and reduce appetite, making you feel fuller longer and thereby lowering your overall calorie intake.3
How to incorporate more mushrooms into your diet
When buying mushrooms at the market, chose ones that are firm, dry, and unbruised. Avoid mushrooms that appear slimy or withered. Store mushrooms in the refrigerator and do not wash or trim them until ready for use.
Make stuffed portabella mushrooms by filling them with your favorite ingredients and baking.
- Sauté any type of mushroom with onions for a quick and tasty side dish
- Add raw sliced crimini mushrooms or white mushrooms to top any salad
- Make stuffed portabella mushrooms by filling them with your favorite ingredients and baking
- Add sliced mushrooms to omelets, breakfast scrambles and quiches
- Grill portabella mushrooms and use them on sandwiches or in wraps.
Potential health risks of consuming mushrooms
Although wild mushrooms have been part of the human diet for several centuries, uncultivated wild mushrooms may pose a risk to those unable to distinguish between those safe and dangerous for consumption.
Eating wild mushrooms that are toxic to humans can cause severe illness and sometimes even death. Studies have also shown that some wild mushrooms contain high levels of heavy metals and other harmful chemicals.5
In order to avoid these dangers, it is best to consume mushrooms that have been cultivated under appropriate conditions.
Consuming beta-glucans is believed to be safe for most people. However, since beta-glucans are capable of stimulating immune function, this may be a risk for those with autoimmune diseases such as rheumatoid arthritis, lupus, asthma, and multiple sclerosis. Researchers have yet to conclude whether or not large amounts of beta-glucan intake has any negative effects on those suffering from these conditions.5
It is the total diet or overall eating pattern that is most important in disease prevention and achieving good health. It is better to eat a diet with variety than to concentrate on individual foods as the key to good health.
Written by: Megan Ware, RDN, LD, registered dietitian and nutritionist