My doctor and I discovered an issue with biotin supplements and I felt like I needed to share my experience. He now asks all his patients who are on levo/synthroid if they take this vitamin.
If you have good TSH numbers but still feel terrible and are taking biotin please keep reading.
I have been meaning to post this for about a year. While this is old new for me I thought it might be helpful for someone else.
In my case I am on levothroxine .75 mcg and cytomel 5 mcg. At the time of the following lab work I was taking the following vitamins, too:
- Vitamin C
- Glucosamine and chondroitin
My friend suggested I was taking too many vitamins and to have a sit down with my doctor, so I did. I emailed him my list of vitamins before hand and h printed out all the medical info on the above vitamins for our appointment.
This is when we both discovered that BIOTIN can give false low TSH numbers. Yes. You read that correctly.
Like many hypothyroid patients I was taking the biotin to “help” with my thinning hair and eyebrows.
He had me stop taking biotin for a month and retest.
I went from TSH 1.4 to TSH 8.1!
We couldn’t believe it. He had me double the cytomel (now two 5 mcg pills) and retest in a few weeks.
Here’s what I was taking. Max strength 10,000 mcg per pill (I was taking 1 a day for about 6 months). My doctor ok’d this over the phone but he didn’t ask what strength and I didn’t know that was important.
Please, please if your numbers look “normal” but you still feel bad and you take Biotin please consider talking to your doctor, stopping Biotin, then retesting after 1 month.
YMMV, but it might make a big difference for you. It has for me.
Sources: I can not find the article that my doctor printed off his his own database, but try googling these phrases:
- biotin interference on tsh and free thyroid hormone measurement.
- Biotin TSH
- “which revealed that biotin may interfere with the most commonly used thyrotropin and thyroid hormone assays. “
The above article tests the impact on children so the dosages mentioned are for a child. Still, by looking at the numbers we can still see how it could impact an adult.
Biotin dosage on the test subjects: “2 to 15 mg per kilogram of body weight per day) [more] than the dietary reference intake in children (5 to 25 μg per kilogram per day)” because of inherited metabolic diseases they had.
Now that I am no longer taking biotin:
- I can now wake up at/around 8 when before I could barely crawl out of bed at 10.
- I am not feeling motivated to run/jog again yet, but I am able to take a walk or use my rowing machine 1- 3 times a week.
- I have experienced no weight loss, but I do feel better than I did when I was taking the biotin.
Overall, My TSH went from 1.4, to 8.1 after Biotin was removed, then back down to 0.71 on after Cytomel was upped to 10 mg a day.
It’s worth asking your doctor about it if you take biotin.
Remember- the only person who truly knows your body is you, and you’re also your best advocate. So, arm yourself with information, take good notes about your symptoms and stay optimistic!