Have you heard of Ganoderma lucidum? Maybe you know it by its other name, reishi mushroom? If not, I predict that eventually somebody will tell you about the benefits of Ganoderma lucidum because it’s all over the internet. There is even Ganoderma lucidum coffee! Because there is so much being said about this mushroom on the web, I want to try to level the playing field by looking at what the research says as well as give people an idea of possible side effects. That way you will have a better idea if Ganoderma lucidum it is right for you.
What is Ganoderma ?
As I mentioned above, Ganoderma lucidum is a type of mushroom. There are over 5000 types of mushrooms, and reishi mushroom is one of those. According to its Wikipedia page, another name that may show up in your research is Lingzhi mushroom. For a much more comprehensive review of Ganoderma, its chemistry, history, and brief review of its medical use, see this book chapter.
Reishi mushroom appears to have a variety of specialized molecules which might help it work in many different ways. Some of the Ganoderma extracts include long-chain sugar molecules (polysaccharides), including beta glucans. The chemistry of these compounds is complex and I won’t go into it here.
Rather, for the rest of this review I will focus on the actual scientific studies that have been done on Ganoderma lucidum to see what has been uncovered. That way, we can cut through the hype and see what the facts are.
Most websites that discuss Ganoderma lucidum only talk about the research. From what I’ve been able to gather, few websites actually show you the research. Therefore, for this review I will break the research down according to the major claims being made about reishi mushroom. I’ll also put that research in context for easier understanding and link to the research so you can see it for yourself. From what I could gather, it appears that the majority Ganoderma research stems from China and neighboring countries.
Ganoderma and blood pressure
I searched the National Library of Medicine for “ganoderma lucidum blood pressure” and found the following relevant studies:
In 1990, researchers in Tokyo noted that Ganoderma lowered blood pressure in anesthetized rats and rabbits. While it did not reduce heart rate, researchers proposed that the blood pressure lowering effect was the result of the mushroom depressing the sympathetic nervous system (the part of the nervous system that usually causes bodily functions to speed up). In other words, by reducing the effects of the sympathetic nervous system, blood pressure should be reduced.
In a study published in 2012 in the British Journal of Nutrition,26 people received 1.44 grams of Ganoderma lucidum a day (or placebo) for 12 weeks. 23 people completed the study.
This study noted no change in blood pressure or body mass index (BMI) in either placebo or Ganoderma groups. However, there was a small decrease in insulin levels and triglyceride levels and an increase in HDL levels. I’m unable to tell from the summary of this study if these effects were ” statistically significant” or not.
These were the only Ganoderma blood pressure studies I found. If that’s all there is, if we look at the recent research, then we have a study from 1990—using rats and rabbits— saying it works, and a study from 2012—using humans— indicating that Ganoderma doesn’t work.
This is important because there are a LOT of people on the internet saying reishi mushroom helps (some even say “cures”) high blood pressure. Other than claims, made by people we don’t know, I’d only ask where is the proof?
Ganoderma and immunity
While in the National Library of Medicine, I searched for “Ganoderma immune” and ” Ganoderma immunity” and discovered these studies:
In a 2012 study published in Frontiers in Pharmacology, researchers noted that a Ganoderma extract stimulated natural killer cell activity (NK cells) and other parts of the immune system in mice. The extract seemed to slow the growth of lung cancer cells but did not kill off the lung cancer cells.
In a study published in 2012 in the Journal of Drug Targeting, Ganoderma improved the anti-tumor effects various of immune cells that were battling mouse skin cancer.
A Ganoderma extract has also shown effective in ramping up immunity in the grouper fish, as was published in 2012 in the journal, Fish and Shellfish Immunity.
In a test tube study from 2012 published in the Journal of Agriculture and Food Chemistry, a Ganoderma extract activated human NK cells and T cells. This was a test tube study but did use human cells, which is good.
In 2008 Chinese researchers noted that at higher concentrations, Ganoderma extract might have toxic effect on human cells. The entire study can be read from the link I provided. On the last page of the study researches make the following statements that I feel are worth reading —especially for those who currently have cancer
- ” We believe that it cannot be concluded with certainty that G. lucidum causes
immunostimulation. Given that there were consistent significant decreases in cell viability
demonstrated, this suggests that G. lucidum does cause toxicity in cells of the immune system.”
- “Therefore, if patients are willing to use G. lucidum as an adjunctive to chemotherapy at lower
concentrations, caution should be used, as the potential for toxicity does appear to exist.”
- ”Additionally, further research is required to verify plasma concentrations after oral use of G. lucidum to determine whether high toxic levels are reached.”
- ”As well, caution needs to be exercised when planning studies of the use of G. lucidum or
its extracts in the therapy of patients with cancer.”
There is a lot of research (mostly coming from China) on the immune benefits of Ganoderma and various extracts from this mushroom. While the research looks promising, most of the research seems to be test tube studies and those that use lab mice. The lack of human research is unfortunate.
Ganoderma and arthritis
In a study published in 2007 in the journal, Arthritis and Rheumatism, 65 people with rheumatoid arthritis (RA) were randomly given 2.4 grams of Ganoderma (32 people) or a placebo (33) for 24 weeks. Those getting Ganoderma were also given 2.4 grams of another herb called San Miao San (SMS). Blood tests were taken and people completed questioners to gauge their pain level.
Significant improvements in pain were recorded in those getting the Ganoderma and SMS combination. There were no changes however in any immune system cells measured in the investigation.
In a human study conducted in 2006, researchers in Hong Kong noted that the combination of Ganoderma and SMS reduced levels of an inflammatory protein called cytokine IL-18 compared to placebo.
My question for these two studies are was it the ganoderma or SMS that seemed to cause beneficial effects —or a combination of both?
Ganoderma and diabetes
I searched the national library of medicine for ” Ganoderma diabetes” and discovered these studies:
In 2012 researchers noted that a Ganoderma extract reduced blood sugar in type 2 diabetic mice. The amounts used were 50 milligrams per kilogram of body weight and 100 millograms per kilogram of body weight.
How much is this in human terms? There are 2.2 pounds in a kilogram. So, a 200 pound person would weigh 200/2.2 = 90.9 kilograms. For a person, this would be between 4.5 grams per day 9.0 grams per day.
In a human study in 2012, published in the British Journal of Nutrition, researchers in noted Ganoderma might have “mild anti-diabetic effects” after 12 weeks of use. These researchers used 1.44 grams of ganoderma per day to achieve these effects.
The majority of ganoderma-diabetes research I saw, used mice or was conducted in test tubes. Compared to the blood sugar lowering effects a 20 minute walk, I am currently, I am not impressed with the effects of ganoderma.
Ganoderma lucidum and cancer
There are several studies of how reishi mushroom interacts with cancer. Here are some of those studies. For additional information on this area, see the Memorial Sloan Kettering Cancer Center.
In a 2012 study published in the journal, Evidence-Based Complementary and Alternative Medicine, researchers in China noted that Ganoderma reduced fatigue in 48 women who had breast cancer.
This was a “pilot study” (preliminary study) that’s often done to see if something might work or not. I’m looking forward to seeing a larger trial conducted by these researchers.
In a test tube study published in 2011, researchers noted that Ganoderma inhibited ovarian cancer cell growth and also increased levels of antioxidant defenses catalase and SOD (superoxide dismutase).
Tip. Also see my review of the anti-aging supplement, Protandim which is also alleged to increase SOD and catalase levels.
In a 2006 test tube study, Ganoderma inhibited the spread of colon cancer cells. Again, this was in a test tube, not in a human being.
In 2004 reishi mushroom was shown to slow the growth of breast cancer cells in a test tube study. This study was published in the journal, Nutrition and Cancer.
In a study published in the journal, Nutrition and Cancer in 2011, researchers noted that Ganoderma lucidum (reishi mushroom) caused cell death (apoptosis) in a type of breast cancer cell. This was actually a test tube study, so it did not prove Ganoderma cured breast cancer in people. I’ve linked to the entire study for those who are interested.
In a study published in 2012 in the journal, PLoS One, Ganoderma was shown to “prevent” colon cancer in mice. I’ve linked to the entire study.
BreastDefend is a dietary supplement which contains extracts from several mushrooms including Ganoderma lucidum. In 2012 researchers implanted human breast cancer cells into mice and noted that BreastDefend inhibited the spread of breast cancer to lung tissue in the mice. This is interesting, but was it Ganoderma lucidum that did this or was it one of the other types of mushrooms —or a result of the effects of all of the mushroom types?
There are a lot of studies of Ganoderma and cancer, and I did not list them all here. While I like that there are studies in this area, when I look at the research as a whole, I see mostly test tube studies and studies of lab mice. I only found 1 human study using Ganoderma mushrooms— and that was a preliminary study of cancer-related fatigue.
As such, I can’t say if Ganoderma mushroom extracts prevent cancer or cure cancer in those who already have the disease.
My conclusions seem to be in line with those of a 2012 review of Ganoderma and cancer by the Cochrane Database which basically states that it’s too soon to tell if it works or not and while it may be something to look at —when used alongside conventional treatments —rishi mushroom alone should not be used as a first choice to battle cancer.
Ganoderma and the prostate
Ganoderma appears to have 5-alpha-reductase inhibitor activity. As such, there is some research on prostate issues.
In a 2012 study Ganoderma reduced prostate size in rats. PSA levels were also decreased.
In 2008, 88 men with lower urinary track infection symptoms were given Ganoderma lucidum (6 mg per day) or a placebo for 12 weeks. The men getting Ganoderma reported more improvement in urinary symptoms than those getting a placebo. No changes in testosterone, PSA, or prostate size were noted.
Ganoderma and the heart
Some websites claim that Ganoderma improves the cardiovascular system. In a study published in 2009, a Ganoderma lucidium extract improved various fat burning enzymes (in the Krebs cycle) in rats. A mouse study published in 2012 noted that ganoderma— given to mice at a level of 100 and 250 milligrams per kilogram— reduced total cholesterol and LDL.
Ganoderma also has antioxidant properties which might help the heart and cardiovascular system. That’s good, but I was unable to find any research showing that it reduced the risk of a heart attack or improved the ability to exercise.
Ganoderma and weight loss
I saw no evidence that Ganoderma helps people lose weight. I only mention this because of the study, above noting that the mushroom extract may increase some enzymes that help us burn fat. Burning fat and weight loss are two different things. Also, the 2012 human study in the British Journal of Nutrition, mentioned previously, saw no change in Body Mass Index when it was given to people for 12 weeks.
Ganoderma lucidum and insomnia
Several websites discuss how Ganoderma has a “calming effect” on nerves and can be used as a natural sleep aid. But does it work? I searched the national library of medicine for “Ganoderma lucidum insomnia” and found this 2012 study noting that it helped rats sleep better. Another study, from 2007 noted that Ganoderma helped rats, treated with the anti-anxiety drug, pentobarbital, sleep better too. I didn’t see any studies using humans.
I also checked the website ClinicalTrials.gov to see if any research was being done. I found 3 completed human trials listed on Ganoderma lucidum – involving cancer, Parkinson’s and rheumatoid arthritis. Unfortunately the website does not list the results of this trials.
There are a lot of products being sold on the internet that contain reishi mushroom. Some of these products are coffees and teas while others are pills and powders containing this mushroom or specific extracts. Websites for many of these products make a lot of claims about the benefits; however, as far as I can tell, very few of these products have been clinically shown to have any effect in humans.
Therefore, I can’t tell how effective any of these products would be for a human being. The easy answer would be to get a complete blood test before using a product and get a similar blood test a month later, to see if anything changed.
Another thing to consider is whether the supplement gives you the whole mushroom or a specific extract of the mushroom. This is important because research on certain conditions sometimes use extracts of ganoderma. As far as I can tell, most supplements contain the whole mushroom.
But, for people who have serious medical problems like cancer, HIV, arthritis, etc., I recommend speaking to your doctor before experimenting with Ganoderma supplements—including coffee and teas. That’s because I don’t know how these products interact with health conditions or medications.
Ganoderma lucidum side effects
There seem to be very few human studies conducted so far on the effects of reishi mushrooms, so side effects from taking it long term are unknown as far as I can tell. That said, here are some theoretical potential side effects based on the little bit of research done so far.
Ganoderma might have a blood pressure lowering effect.
Ganoderma might be a natural blood thinner.
The Sloan-Kettering Cancer Center website gives 2 case reports of liver toxicity (including one death) and a bout of diarrhea following Ganoderma use.
People who take any medications or have health issues—including arthritis and HIV— should see their doctor before using Ganoderma supplements.
Does it work?
I like that researchers are looking at Ganoderma but I don’t like that about 99% of that research is composed of lab mice and test tube studies. Therefore, I don’t think anybody can say for certain if Ganoderma helps people or not. Despite the amazing claims made on the internet, there just isn’t enough evidence either way. If you’re healthy, I don’t think Ganoderma will hurt anybody, especially if it’s used occasionally. Before trying Ganoderma, I think it’s a good idea to get a full blood test first —and do it again after about a month to see if anything has changed for the better. I also think it’s best to start off by using less than the recommended amount just to see how you respond.
What do you think?