I understand that Marmite contains biotin via the yeast extract. Does this mean no Marmite on toast for a few days before blood test please?
Blood test, Marmite: I understand that Marmite... - Thyroid UK
Blood test, Marmite
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Ordinary consumption of foods that contain biotin is NOT a problem.
You would find it hard to consume 100 micrograms of biotin in ordinary foods - even foods which are sometimes considered high in biotin.
helvella - Biotin supplementation and testing
A short article about how and why biotin can affect blood tests. Includes information about how to avoid any problems.
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'no Marmite on toast for a few days'
Absolutely no need whatsoever to torture yourself in that way! 🤣
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although marmite does contain gluten unless you find an impersonator product (Sainsbury’s I think) that is GF 👏 (if that is relevant for you) 🌱
After experiencing several blood test results which didn't actually reflect how well my levothyroxine dose had and continued to make me feel well for 14 years I had to have a retest after 6 weeks. After inspecting the ingredients on my multivitamins and other supplements (including Biotin and Quercetin ) I knocked them all off for a week before the blood test. Lo and behold it came back within the acceptable levels. Not sure if it was a fluke but I will do the same next time and if it works then my annual wrangling match with the doctor will hopefully be a thing of the past. Happy GP = Happy Me!