Therapeutic uses of Reishi
Among the wide range of diseases claimed to be successfully ‘treated*‘ by Reishi are found to be:
- hepatitis
- hyper-cholesterolemia
- diabetes
- neoplasm
- immunodeficiency
- leukopenia
- atherosclerosis
- haemorrhoids
- chronic fatigue
- insomnia
- dizziness caused by neurasthenia
in addition to cancer, bronchitis and hypertension*.
Amount of research publications devoted to Reishi over the years.
This versatility is due to the large number of bioactive compounds isolated from this fungus, as described earlier. Research is increasing every year.
However, we want to emphasise that the majority of research so far has been performed with animals (in vivo) and in the lab (in vitro). Research with human volunteers is still scarce.
- Immunomodulation
Products that can support and enhance the functioning of our immune system improve our health in terms of improved resistance against malignant or pre-malignant cells. Anti-inflammatory, anti-viral and anti-bacterial effects are also an effect of a well-functioning immune system. Many Reishi products on the market are labeled or promoted as immunomodulating agents and there is considerable research-based evidence to support these claims. Autoimmune diseases like allergies and arthritis can be influenced in a positive way, by normalising the immune response that caused them. Some research also found that Reishi has an anti-histamine effect, which can be beneficial when treating asthma and specific allergies.
Summarising in brief: the proliferation, maturation and activities of both T and B lympocytes, NK cells and dendritic cells improved significantly during both lab and animal tests. Cytokine production was also triggered. All of these are key factors in a well functioning immune system and therefore key factors for our general health and well-being.
Taking into account that our immune system is under continuous siege and that, apart from that, our immune function starts declining already around our 35th birthday an immune supporting supplement such as Reishi can be considered a good addition to our diet. The beta-glucan fractions are the most important constituents for immune support.
- Cardiovascular effects
The effect of Reishi on the cardiovascular system has been investigated in depth. The triterpenes found in Reishi were found to have a normalising effect on elevated cholesterol levels, which in turn can affect high blood pressure (by reducing the potential plaque buildup in arteries). Several reports also mention a direct normalising effect on blood pressure. Platelet aggregation decreased, probably because of the presence of trace amounts of adenosine in synergy with triterpenes. Direct and indirect lipid peroxidation (a side effect of normalised cholesterol levels) and anti-oxidant effects have been demonstrated in animal and lab experiments.
- Rheumatoid Arthritis
Rheumatoid artritis is an auto-immune disorder. The effect of Reishi on patients with rheumatoid arthritis has been studied in two clinical trials. The outcome was very good. However, both trials used a combination of Reishi plus San-Miao-Wan (a TCM herbal formula), therefore making it difficult to attribute the positive outcomes to the individual agents.
- Chronic fatigue syndrome
CFS is also known as ME. It is believed that ME is an auto-immune disease. A multicenter, double-blind, randomised, placebo-controlled trial was conducted in China. A Reishi extract was administered for 8 weeks, resulting in a reduced sense of fatigue and improved quality of life. This again confirms Reishi’s effect on the immune system. Because the effect is balancing, there are no unwanted side effects.
- Anti-oxidant actions
Anti-oxidants protect cellular components from oxidative damage, which can decrease the risk of mutations and carcinogenesis and can also protect immune cells, allowing them to maintain immune surveillance and response.Various components of Reishi, in particular beta-glucans, protein-bound and peptide-linked polysaccharides and triterpenoids did show anti-oxidant activity in lab tests. However, a direct link has not been established between the anti-oxidant properties of Reishi and its immunomodulatory and anticancer effects, and whether Reishi acts as an anti-oxidant or pro-oxidant may depend on concentration and environment. Research shows conflicting results, so it might be wise not to rely on Reishi as an anti-oxidant.
- Anti-viral and anti-bacterial actions
Polysaccharide-bound proteins from Reishi showed inhibitory effects on Herpes Simplex Virus type 1 (HSV-1), Herpes Simplex Virus type 2 (HSV-2), and Vesicular Stomatitis Virus (VSV – New Jersey strain) in a lab test. Using the plaque reduction method, a significant inhibitory effect was seen at doses that showed no cytotoxicity.
A dried hot water extract of Reishi taken orally was used as the sole treatment for postherpetic (varicella zoster virus) neuralgia in 4 elderly patients. This treatment was reported to dramatically decrease pain and promote the healing of lesions without any toxicity, even at very high doses.
- The antimicrobial combination of Reishi with four commonly used antibioticsresulted in an additive or synergistic effect in most, but not all, instances, with apparent antagonism against cefazolin and ampicillin effects on Proteus vulgaris (known to cause urinary tract infections and wound infections).
- Anti-cancer
Reishi extracts are popular supplements taken by healthy individuals to support the immune system in general and by cancer patients along with conventional therapies, to reduce the side effects of those therapies (including the negative effects on the immune function, which can lead to secondary infections and indirectly can promote metastasis). The chemopreventive activities of the mushroom on prostate cancer were demonstrated by a triterpenoid-rich extract of Reishi that suppressed the ventral prostate growth induced by testosterone.
Reishi appears to have a positive effect in inflammatory breast-cancer, but should not be used in hormone-related breast cancers.
However, whether the antitumor effect of Reishi is a direct one or is mediated via the immune system is not clear. The research results with humans seem to indicate that the antitumor effects are a side effect of Reishi’s effects on the immune system. Much more research with human volunteers is needed – the majority of research so far was in vivo and in vitro.
- Anti-diabetic effects
It seems that polysaccharide-rich extracts can be beneficial for diabetics. In several controlled animal studies the oral administration of a hot water extract was found to lower serum glucose levels. The first effects were seen after one week. The extract markedly reduced levels of phosphoenol-pyruvate carboxykinase (PEPCK).
Serum insulin levels increased (when compared to the nontreated diabetic group) and glucose levels decreased in a dose-dependent way. Levels of non-enzymic and enzymic anti-oxidants increased and lipid peroxidation levels decreased. Therefore, in addition to its glycemic modulation, treatment with this hot water extract helped to decrease oxidative stress.
There are a few human trials with similar positive results. Overall, the data from several studies suggests that taking a Reishi extract might help in modulating blood glucose levels. However, these studies were performed mostly in animals. More support from well-planned human clinical studies is needed with and without combination with conventional medicines to be able to make more definitive claims.
- Liver protection, Ulcers