The reishi mushroom, also known as Ganoderma lucidum and lingzhi, is a fungus that grows in various hot and humid locations in Asia.
For many years, this fungus has been a staple in Eastern medicine.
Within the mushroom, there are several molecules, including triterpenoids, polysaccharides and peptidoglycans, that may be responsible for its health effects.
While the mushrooms themselves can be eaten fresh, it is also common to use powdered forms of the mushroom or extracts that contain these specific molecules.
These different forms have been tested in cell, animal and human studies.
1. Boost the Immune System
One of the most important effects of the reishi mushroom is that it can boost your immune system.
While some details are still uncertain, test-tube studies have shown that reishi can affect the genes in white blood cells, which are critical parts of your immune system.
What’s more, these studies have found that some forms of reishi may alter inflammation pathways in white blood cells.
Research in cancer patients has shown that some of the molecules found in the mushroom can increase the activity of a type of white blood cell called natural killer cells.
Natural killer cells fight infections and cancer in the body.
Another study found that reishi can increase the number of other white blood cells (lymphocytes) in those with colorectal cancer (2Trusted Source).
Although most immune system benefits of reishi mushroom have been seen in those who are ill, some evidence has shown that it can help healthy people, too.
In one study, the fungus improved lymphocyte function, which helps fight infections and cancer, in athletes exposed to stressful conditions.
However, other research in healthy adults showed no improvement in immune function or inflammation after 4 weeks of taking reishi extract (10Trusted Source).
Overall, it is clear that reishi impacts white blood cells and immune function. More research is needed to determine the extent of the benefits in the healthy and ill.
2. Anti-Cancer Properties
Many people consume this fungus due to its potential cancer-fighting properties.
In fact, one study of over 4,000 breast cancer survivors found that around 59% consumed reishi mushroom (13Trusted Source).
Additionally, several test-tube studies have shown that it can lead to the death of cancer cells.
Yet the results of these studies do not necessarily equate to effectiveness in animals or humans.
Some research has investigated if reishi could be beneficial for prostate cancer due to its effects on the hormone testosterone.
While one case study showed that molecules found in this mushroom may reverse prostate cancer in humans, a larger follow-up study did not support these findings.
Reishi mushroom has also been studied for its role in preventing or fighting colorectal cancer.
Some research showed that one year of treatment with reishi decreased the number and size of tumors in the large intestine (21Trusted Source).
What’s more, a detailed report of multiple studies indicated that the mushroom can beneficially affect cancer patients.
These benefits included increasing the activity of the body’s white blood cells, which help fight cancer, and improving quality of life in cancer patients.
However, researchers state that reishi should be administered in combination with traditional treatment rather than replacing it.
What’s more, many of the studies of reishi mushroom and cancer were not high-quality. Because of this, much more research is needed (11, 23Trusted Source).
3. Could Fight Fatigue and Depression
Reishi’s effects on the immune system are often most emphasized, but it has other potential advantages as well.
These include reduced fatigue and depression, as well as improved quality of life.
One study examined its effects in 132 people with neurasthenia, a poorly defined condition associated with aches, pains, dizziness, headaches and irritability.
The researchers found that fatigue was reduced and well-being was improved after 8 weeks of taking the supplements.
Another study found that fatigue was reduced and quality of life was improved after 4 weeks of taking reishi powder in a group of 48 breast cancer survivors (25Trusted Source).
What’s more, the people in the study also experienced less anxiety and depression.
While reishi mushroom may hold promise for people with certain diseases or illnesses, it is not clear if it would benefit those who are otherwise healthy.
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