A week or so earlier there was a thread on this topic but I found it got locked.
Since I myself take resveratrol+curcumin+quercetin combo as recommended by Imminst.org, I think the potential danger of mixing a number of P450 inhibitors deserves a serious discussion so here I am strating a new thread.
I did a through homework by reading at least first 3 pages of articles for each search result. All studies seem to agree that resveratrol, curcumin, quercetin and bioperine are potent inhibitors of P450.
Now I have always thought P450 is only involved in drug metabolism but it turned out not so simple. P450 is a family of the most powerful detox enzymes in our system, it breaks down all kinds of harmful chemicals we inhale and ingest everyday, e.g. air pollutants, food additives and pesticides to name a few. As such, it comes as no surprise that most detox programs rely on supplements that induce(amplify) P450 activity and unfortunately resveratrol, curcumin, quercetin and bioperine are doing exactly the opposite.
Then I came across this article. It appears to be a press release by one resveratrol vender.
A couple of points caught my eyes:
"Claims that resveratrol is not "biologically available" are mistaken. Resveratrol is linked (conjugated) to a molecule called glucuronate in the liver, which extends its life in the blood circulation up to 9 hours. The delivery of resveratrol to tissues is then facilitated by an enzyme called glucuronidase that releases resveratrol."
It appears that resveratrol is inherently bioavailable and there is no need to tweak it for better absorption.
"Resveratrol is not suggested for growing children or pregnant females."
I did more research on this one and learned that Resveratrol retards growth of fetus and children by suppressing new blood vessel formation. I would think that it may be wise for bodybuilders and muscle bulking athletes too, not to supplement resveratrol.
"Prescription medications should not be taken at the same time as resveratrol pills. Resveratrol and quercetin inhibit detox (cytochrome p450) enzymes in the liver which protectively dull the effects of medications. If these enzymes are inhibited, medications may work too well, for example, causing blood pressure to drop a bit too far if taking blood pressure pills, or causing liver problems if taking statin cholesterol-lowering drugs. Since resveratrol is rapidly metabolized, these effects are usually transitory. This is similar to the problem of drinking grapefruit juice prior to taking medications. If in need of more information, ask your pharmacist about cytochrome p450 reactions."
Then it hit me. I take statin and remember that I was cautioned not to take more than a cup of grapefruit juice a day and now I understand why: grapefruit juice inhibits P450 and it is this exact P450 inhibiting side effect that resveratrol, curcumin, quercetin and bioperine share. I dialed my doctor right away only to hear him barking at me to immediately quit taking the combo. According to him resveratrol, curcumin, quercetin and bioperine's P450 inhibition are orders of magnitude higher than that of grapefruit juice. He also disagrees with the statement "these effects are usually transitory".
"Don't go wild with curry either" and he hung up/
Will see him in his office next week and meanwhile I further searched the net and found that it is not just statins but myriad of drugs including popular NSAIDs, antibiotics, antifungals, contraceptives, benzos, SSRIs, arthritis and cardiovascular/heart/BP medications that should not be mixed with P450 inhibitor. I would guess red yeast rice is no exception either.
My bottom line:
If you are on prescription medications, you should not take any of resveratrol, curcumin, quercetin and bioperine without first consulting your doctor. If you are not on prescription medications, you should still be cautious on mixing these four since no matter how beneficial they are thought to be, they share one undeniable adverse effect that they all potently inhibit our body's natural detox system, P450, which IMO should be working in overdrive mode 24/7 as we breathe and eat plenty of harmful pollutants and chemicals every day. I definitely wouldn't go for triple/quadruple combo whammy, maybe not even mixing any two of the four. I would go for just one in small dose. But as for me for now, I have no choice but quitting them all at once as strongly advised by my doctor.
Lesson I learned:
There is no panacea. Not surprising albeit disappointing. Supplementing, like anything else in life, is all about compromise and don't let anyone tell you otherwise.