Beta-Sitosterol is not a cannabis flavonoid, despite reports to the contrary from dozens of prominent cannabis industry websites. In fact, Beta-Sitosterol isn’t a flavonoid at all – it’s a plant sterol, and this is easily confirmed with a quick review of the scientific literature.
During extensive flavonoid research for The Big Book of Terps, this author reviewed 52 studies that focused on β-Sitosterol. Not one of these studies referred to this compound as a flavonoid. In fact, many of the studies referred to β-Sitosterol as a plant sterol, while in the same study, referred to flavonoids separately. However, the cannabis industry insists that this compound is a flavonoid:
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Interestingly, of 15 unique cannabis samples that I sent to ACS Laboratory in Florida, USA, for flavonoid testing, all but one returned β-Sitosterol as the #1 flavonoid in the samples by concentration. I had sent these samples for testing in January 2020, before fully realizing that β-Sitosterol is not a flavonoid.
I consulted with prominent cannabis researcher David Dawson, who concurred that the compound is a plant sterol and not a flavonoid. I then emailed my contacts at ACS Laboratory, asking why β-Sitosterol was being included for testing in the company’s flavonoid panel. The response:
“[Dr. Sun] put the flavonoid panel together a few years ago at the request of a customer who wanted that analyte on the list. She admitted she has not done extensive research on beta-sitosterol, as this panel is typically in low demand.”
Dr. Sun is the Chief Scientist for ACS Laboratory.
After removing β-Sitosterol from the flavonoid test results, it became clear that the #1 flavonoid in all but one of the samples tested was Cannflavin A.
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However, this situation also made it obvious that, although β-Sitosterol is not a flavonoid, it is a common and important compound that appears to occur in every cannabis strain. Further research shows that β-Sitosterol has significant medical value, securing an individual chapter that discusses this compound in The Big Book of Terps, which was initially meant to only cover terpenes and flavonoids.
Conclusion; β-Sitosterol is a valuable plant sterol in cannabis. It is not a flavonoid.
Recommendation; Cannabis websites need to better research the information they provide their visitors – the credibility of the entire industry is at stake.