Research: Majority of Reishi supplements sold in the US turns out to be useless

Last month (Aug 2017) a study called “Evaluation on quality consistency of Ganoderma lucidum dietary supplements collected in the United States” was published.

Nineteen Reishi (Ganoderma lucidum) dietary supplements were purchased, in February or March 2015, directly from general e-commerce sites such as Amazon and eBay in the United States. One -authenticated- Reishi fruiting body was used as a control.

The outcome was unexpected – ah well, let’s just say it, it was shocking!

All products were tested for triterpenes, polysaccharides and beta-glucan, and on top of that for authenticity (is it really Reishi?).
Only 8 of the 19 products contained triterpenes that were actually Reishi triterpenes or something at least quite close to that.

Starch-like polysaccharides (alpha-glucans) are used a lot as excipients / flow agents or fillers in dietary supplements. They are also used to ‘spike’ mushroom supplements that use ‘polysaccharides’ as a potency marker. ‘Polysaccharides’ are not reliable as a quality marker – most polysaccharides are not bioactive and the percentages can be manipulated easily.

Starch is also present in large quantities if the a mushroom supplement is not produced from fruiting bodies but from mycelium grown on grains/rice (= substrate) – the undigested substrate is starch. It has no therapeutic potential.

Normally speaking a Reishi fruiting body is starch-free after having been extracted. However, it is no longer a secret that the majority of US-produced mushroom products are not based on fruiting bodies but on biomass (the combination of mycelium and the substrate it grows in). The outcome of this study seems to confirm that once again: only 6 of the 19 products were starch-free.

Beta-glucans are the other main bioactive ingredients in Reishi. The paper found only 5 of the 19 products contained beta-glucans. When tested for authenticity, the same 5 products tested as being authentic.

A final test was determining the molecular weight of the beta-glucan fractions and to use this as a quality marker. Previous papers have shown that these high molecular weight beta-glucans are the most bioactive fractions and are suitable to be used as a quality marker. Again, only 5 out of 19 products contained this marker compound.

This study shows the quality consistency of Reishi dietary supplements collected in the USA was extremely poor.

The full text can be read here:

Rhodiola rosea extract may improve anxiety, stress and mood

Daily intake of a Rhodiola rosea L. extract may improve various measures of mood in people with mild anxiety, says a new study from England.

depressionData from 81 mildly anxious students indicated that 14 days of supplementation with a Rhodiola rosea extract significantly reduced self-reported anxiety and stress.

Improvements in self-reported anger, confusion, and depression were also reported by the researchers.

“Although Rhodiola rosea has been used traditionally to relieve a range of symptoms of stress related disorders, to our knowledge this is the first study to demonstrate the efficacy of Rhodiola rosea  in the treatment of mild anxiety,” wrote Mark Cropley, Adrian Banks, and Julia Boyle from the University of Surrey in Phytotherapy Research .

Study details

Cropley, Banks, and Boyle recruited 81 students with an average age of 21 to participate in their 14-day study. The participants were assigned to receive two 200 mg doses per day of the Rhodiola rosea extract or no treatment.

Self-reported measures indicated that Rhodiola group demonstrated a significant reduction in self-reported anxiety and stress. Secondary endpoints, including anger, confusion and depression, also improved over the 14 day trial. Self-reported “total mood” was also significantly improved in the Rhodiola group.

On the other hand, no changes to measures of cognitive function were reported by the researchers.

Apart from that, the safety and tolerability of the Rhodiola rosea supplements were found to be good.

rhodiola rosea, dried roots

Rhodiola rosea roots are chopped into slices and then dried. These dried raw slices as sold by ORIVeDA are used to prepare a tincture.

“Future research is needed to replicate the current findings, and it would be desirable to supplement the subjective nature of self-reports with more objective indices,” wrote Cropley, Banks, and Boyle. “Clinical interviews could be used to assess mood, and sleep could be assessed via wrist actigraphy or EEG.

“The lack of placebo control is another limitation of this study. It is unlikely that the findings were the result of placebo effects, as changes appeared gradual and were specific to certain measures. As this was a non-placebo RCT, however, we cannot determine a causal relationship, and we cannot exclude that some of the changes were because of time alone or other factors.”

“Overall the results demonstrated that Rhodiola rosea is effective in the treatment of mild anxiety and stress. It improved confusion, anger, and total mood, and was well tolerated.”

Source: Phytotherapy Research
“The Effects of Rhodiola rosea L. Extract on Anxiety, Stress, Cognition and Other Mood Symptoms”
Authors: M. Cropley, A.P. Banks, J. Boyle

An extensive review of Rhodiola rosea with an emphasis on human trials can be found here.