Selenium

[Martina]

I h ave read on this site that selenium is recommended to help the conversion of T4 into T3

My doctor prescribed one 100mcg tablet per day

I know that high levels of selenium are toxic. I'm therefore afraid to take the prescribed dosage on a regular basis lest it might accumulate in the body and cause side-effects

What are your thoughts?

Thank you

[helvella Administrator Thyroid UK]

A very good question. And the deiodinases that convert T4 into T3 are all seleno-proteins so selenium is absolutely essential.

I agree with you. The US RDA is only 55 mcg - and of course your diet will be providing at least some of the selenium you need. Don't think I would take even 50mcg per day as a supplement - maybe 20 to 30mcg?

I do worry by the crazily high dosages available like 150 0r 200mcg. Even allowing for imperfect absorption, etc. that seems way too high to be safe.

How about splitting them? Or taking them on alternate days? Or both? That would get you into what seems to me the sensible zone.

Or just take a few Brazil nuts? Mind, one ounce of them can contain 544 mcg according to ods.od.nih.gov/factsheets/s... !

(Interestingly, as far as I can make out, in the UK selenium can only be prescribed for those with proved deficiency on parenteral nutrition.)

Rod

[Martina in reply to helvella]

Thank you, Rod, for your answer

I definitely agree with you about taking the tablet on alternate days

Do you know what the symptoms are when selenium gets too high?

Could it be that selenium might not be properly absorbed and it accumulates in the body?

Thank you

[helvella Administrator Thyroid UK in reply to helvella]

The Wiki article seems to be quite good:

en.wikipedia.org/wiki/Selenium

From which, to answer your specific question:

"Symptoms of selenosis include a garlic odor on the breath, gastrointestinal disorders, hair loss, sloughing of nails, fatigue, irritability, and neurological damage. Extreme cases of selenosis can result in cirrhosis of the liver, pulmonary edema, and death."

In general that article seems to accept higher doses than I would feel comfortable taking. But there seems to be an awful lot of uncertainty.

Rod

[Leigh1 in reply to helvella]

I take 200mcg a day which my doctor is happy with me taking and i feel fine with that amount. The good thing is that everyone at work has gone down with flu or some sort of virus lately and i haven't caught anything which i put down to taking the Selenium

[helvella Administrator Thyroid UK in reply to helvella]

Just wondering, why did you choose 200mcg?