A component of solving this crisis is medicinal mushrooms. While most store-brought mushrooms, such as the white button mushroom, have no medicinal properties, there are a host of less readily available fungi that have medicinal properties. Enokitake, Shitake, Oyster, and Maitake have variously been shown to reduce blood pressure, lower cholesterol, inhibit tumor growth, and modulate the immune system.
To summarize Chang's 1996 article, we have known that Shitake mushrooms have anti-tumor properties since 1969 (Ikekawa). Chihara (1987) isolated a compound in Shitake mushrooms called lentinan which, through immunopotentiation, is effective at reducing tumor growth. This compound has been proven effective in human trials. Taguchi (1987) showed a significant survival improvement in gastric cancer patients treated with letinan and chemotherapy as compared with those treated with only chemotherapy. Other chemicals from Shitake mushrooms have been shown to improve liver function in Hepatitis B patients, inhibit HIV in vitro, and lower serum cholestoral in high cholesterol mice.
These effects are only a sampling of the medicinal benefits from one particular mushroom species. Given the enormous health gains available the question is: why don't we eat more mushrooms? As I see it there are two answers: The first is simply a question of availability. The average supermarket only stocks the white button mushroom, a non-medicinal species. "Gourmet" varieties, like the medicinal shitake, enokitake, maitake, and oyster, are typically sold at gourmet prices, outside the budget of the average consumer. This issue could be remedied by increased production, which would lower prices and increase availability.
The second factor limiting mushroom consumption is mycophobia, the irrational fear of mushrooms. It is well-known that certain species of mushrooms are poisonous, and some cultures have extrapolated the fear of poisonous mushrooms to the fear of all mushrooms. The English and Irish cultures are well-known mycophobic cultures that traditionally have avoided mushrooms at all cost. Overcoming mycophobia is really a question of education and awareness.
That said, here are some of the other angles from which I've been thinking about mushrooms: