Grapefruit

[Indigourchin]

Hello everyone

Does anyone know if grapefruit juice interferes with T4/T3 uptake? I know if someone is on statins it has to be avoided

I know to avoid Biotin before blood tests but is Nicotimamide ok?

Finally has anyone successfully lowered their cholesterol without statins while on T4/T3, I really need to shift some weight as i also have high oestradiol but finding it hard to do

Thank you in advance, I'm so grateful for this site and all the shared knowledge.

[helvella Administrator Thyroid UK]

The issues with grapefruit and medicines are not to do with uptake - rather how substances are metabolised in the liver. I don't think we are aware of issues with T4 and T3 but someone might know more.

Grapefruit–drug interactions

en.wikipedia.org/wiki/Grape...

The issue with biotin is incredibly specific to biotin and the fact that some assays use a streptin-avidin process which acts as a lock-and-key to bind with biotin.

That isn't to say no other vitamins have any effect but I don't think we have any awareness of significant impacts from any other vitamin. (Except, of course, where the vitamin itself is being tested - e.g. B12.)

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.

helvella.blogspot.com/p/hel...

I'm a bit confused about losing weight and cholesterol in the same sentence?

Many find cholesterol test results change when treated. And inadequate treatment is often found in those with high cholesterol.

[Indigourchin in reply to helvella]

Thank you helvella , very kind of you and i appreciate the links