Sulforaphane and isothiocyanate goitrogen concerns | Rhonda Patrick
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Broccoli sprouts are concentrated sources of sulforaphane, a type of isothiocyanate. Damaging broccoli sprouts – when chewing, chopping, or freezing – triggers an enzymatic reaction in the tiny plants that produces sulforaphane.
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Some concerns have arisen that sulforaphane, an isothiocyanate compound derived from certain cruciferous vegetables, may disrupt thyroid hormone function and potentially act as a goitrogen by competing with iodine uptake. Long-term studies in iodine-deficient or hypothyroid animals showed no ill effects with high dose sulforaphane supplementation, however. While iodine deficiency is rare, a person considering sulforaphane supplementation should consult their physician to have their thyroid hormone levels monitored. In this clip, Dr. Rhonda Patrick describes the potential interaction between sulforaphane and iodine and stresses that iodine-deficient people or those with hypothyroidism should work with their physician to monitor thyroid hormone levels.
Uh-huh. There has been some concern about sulforaphane possibly competing with iodine for transport into the thyroid and hence, you know, a potential what's called goitrogen, which is something that can disrupt the production of thyroid hormones, particularly for people that are iodine deficient which— or have hypothyroidism. Again, that's a concern mostly you find in blogs and stuff. If we actually look at the scientific Yeah. So, there's data, for example, clinical data, healthy people that were— that don't obviously have iodine deficiency or hypothyroidism, but they're healthy and they were given the amount of isothiocyanates. So, sulforaphane is a part of a broader family called isothiocyanates.
They were given the amount that's roughly equivalent to what you'd find in 70 grams of broccoli sprouts daily for a week and there was no negative effects on thyroid hormones, no toxicity on liver or anything like that. So, the question is, what about people— what about the context of iodine deficiency? By the way, that's very rare these days. Yeah. I mean, you just get a sea snack at Whole Foods. Yeah. Well, every— and also just most salt, people are eating things with salt and their salt's iodized mostly if you're getting any type of processed foods and stuff too, right? Mm-hmm. There was a long-term study published last year in animals where rats that were iodine deficient or had hypothyroidism induced by a drug, they were given large quantities of broccoli sprouts. For a long period.
This is a long-term study. And, there was zero effect on thyroid hormones. There was no change in thyroid stimulating hormone, no change in T3 or T4. None of those hormones were affected in these rats that were iodine deficient or had hypothyroidism. In fact, animals that had hypothyroidism, broccoli sprouts actually exerted a beneficial effect on their thyroid because it increased glutathione. Wow, crazy. So, there you have it. You know, should you be concerned if you have hypothyroidism? Potentially. I don't— you know, the thing to do would be to do a baseline thyroid test and then do one after, you know, a month or— or however long of, you know, your broccoli sprouts and/or supplement, right? Measure something. Yeah. I mean, always talk to your doctor with this stuff. Right. You know, that's the best— best advice. But I'm still super excited about it, for sure.
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Sulforaphane News
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- Sulforaphane, derived from broccoli, activates Nrf2, mitigating age-related skin changes and boosting the antioxidant defense system in mice.
- Sulforaphane from broccoli sprouts shows promise in preventing Alzheimer's disease – boosting memory and enhancing mitochondrial function in mice.
