Greg Weber says, "Sulforaphane is well studied to upregulate the Nrf2 pathway. In your
masterclass on antioxidants, one of my takeaways was that xenobiotics are beneficial when they
upregulate Nrf2 more than they cause damage." I agree with that interpretation of my class, Greg.
"According to this line of reasoning, sulforaphane seems to be the best possible xenobiotic to take,
since studies showed it is very good at upregulating Nrf2," makes sense. "Is Dr.
Rhonda Patrick right, that this is an amazing supplement we should be considering taking?
I have seen you state earlier this year that sulforaphane goitrogenic,"
correct, "And it's consistent with your previous writings on isothiocyanates and crucifers.
However, one of the longstanding researchers of sulforaphane, Dr. Jed Fahey
states that this is a misconception of sulforaphane and that they have monitored
thyroid status in their studies and see no ill effects. I'm wondering if you have, or are
planning on taking a deeper look into sulforaphane research or doing writings on the subject?"
Well, I haven't looked at Fahey's research on this, and so I can't really address what he's
saying specifically. What I can say is that sulforaphane does generate thiocyanate ions,
which do inhibit uptake of iodine into the thyroid and mammary glands. Although that is a matter of
the ratio between isothiocyanate, or between thiocyanate ions and iodine. And so
in principle, most uses of sulforaphane, in the context of adequate iodine shouldn't be
an issue, but at some point you're going to run into a... I believe
at some dose you're going to run into a problem with balancing with iodine, especially in people
who have marginal iodine status, but I don't have any studies to back up what point that
is. But I have seen cases of people where they got brain fog when they were taking sulforaphane
and it went away when they took iodine. So I'm not inclined to say that it's
bad because it's goitrogenic, but I am inclined to say, yes, you're right, that it's a great Nrf2
booster. It should be considered a beneficial supplement in that context,
and it does have the drawback that it can inhibit iodine uptake into the thyroid and mammary gland.
Enough iodine in the diet should compensate for that, but if you're using high doses, watch out,
take a look at your dietary iodine, take a look for symptoms of fatigue, brain fog, or anything
else that could be tied to hypothyroidism. And if they develop, tweak the sulforaphane
and iodine ratio to see what can get rid of them. So I think it's,
I'm not against sulforaphane, but I think people should be conscious of the potential downside of
it in order to look out for it, so that if things arise, there's an explanation at easy access,
rather than wondering, "why do I feel like crap?" So if you feel great on sulforaphane,
you probably don't have that issue and you don't have to worry about it. But I do think people
should keep in mind that possibility. Thank you, Greg, for your question.