Myths & Facts

Mushrooms are often associated with vitamin B12, a vitamin commonly found in animal foods. Ground-breaking research at the University of Western Sydney revealed that there are wide-ranging amounts of B12 in mushrooms. Their detailed experiments on mushrooms of all sizes and stages of growth from around Australia conclusively proved that:

1. Mushrooms do have B12 present. It is on both the surface of the mushroom and in the flesh of the mushroom. The majority of B12 is in the surface of the cup of the mushroom.
2. The B12 present is bio-available, in exactly the same form as B12 in beef liver and fish; therefore it is easy to absorb from the intestines.
3. The amount of B12 in mushrooms varies from crop to crop. One serve will provide about 2-4% of the RDI. However, that level may be an important amount over a lifetime for a vegan who loves their mushrooms.

Although mushrooms are not high in B12, they are still the only non-animal fresh food source of B12. See the fact sheet on vitamins and minerals for more information.

This is another indication that the mushroom differs from plants. The mushroom, like humans, generates vitamin D when it is in the sunlight, specifically the UV part of sunlight. This is why wild mushrooms naturally generate 2-40 mcg of vitamin D in 100g serve. Compare that to the 5-15 mcg of vitamin D we need each day. You probably don’t eat wild mushrooms and prefer to buy them from grocers. Well, even putting your mushrooms in the sunshine for a 30-60 minutes will get them to start producing vitamin D.

Exposing commercial mushrooms to sunlight after harvest also triggers the production of vitamin D. Some Australian farmers have produced mushrooms with the daily needs of vitamin D in a single 100g serve, about 3 button mushrooms. Vitamin D mushrooms are also available in Canada, NZ and the USA. For more information, see out fact sheet on Mushrooms and Bones or go to Vitamin D Mushrooms.

No. If there is some residual compost still on the mushroom when you buy them, just brush it off. You can quickly wash whole mushrooms just before preparing a dish to remove the ‘dirt’. Dry them quickly soon after, before cooking or putting in a salad. Don’t wash sliced mushrooms because they will quickly absorb water through the exposed inner flesh. There is no need to peel mushrooms either; they can be consumed as purchased.

There is no evidence that certain fruits, vegetables or even mushrooms make gout worse. In fact, a high consumption of fruit, vegetables and mushrooms is linked to a lower risk of gout. Advice to gout sufferers to avoid foods such as spinach, asparagus and mushrooms is not justified. There is a separate fact sheet that discusses gout, the role of diet, in particular mushrooms, and provides references for those with an interest in science.

In truth, we don’t know but there is some very compelling evidence that women who eat mushrooms have a much lower risk of breast cancer than women who don’t eat mushrooms. There have been three population studies that show that women who include mushrooms in their diet have about half the risk of breast cancer. A meta-analysis of all the research also supported a strong link between mushroom consumption and a lower risk of breast cancer.

It might be that some compounds in mushrooms protect women against breast cancer or it may be some other aspect of their lifestyle that is lowering the risk. This requires further research to determine the role of mushrooms in cancer. Please read the fact sheet on cancer for more information.

Simply put, no. Many people want to avoid gluten in their diets. Mushrooms do not have any gluten, so can be easily used in a gluten-free diet.  There are gluten-free recipes in our recipe collection.