Clear need for B2, but not tolerating it. How to get out of the maze?

[salam]

Maybe taking your B2 sublingually,

I'm already taking it sublingually, 1/2 cap at a time.

Is there any explanation why taking FMN sublingual is better than regular capsules or tablets?

 

[picante]

Is there any explanation why taking FMN sublingual is better than regular capsules or tablets?

Only that it would go straight into the bloodstream instead of going through the digestive tract. Many of us have impaired digestion.

 

[bigmillz]

The B12 oils guy (Greg in Australia) has been telling me that I'll have problems getting my methylation cycle rebooted without B2, and I think he's right. But I've had terrible responses to the two supplements I've tried so far (Source Naturals FMN and Seeking Health B-minus, which is a B-complex). I'm now moving on to R-5'-P and will report back.

Two possibilities I'm investigating:

1. I've been on T3 (thyroid) for several years. Is T4 needed to convert FMN to FAD?
2. Low phosphorus or sodium/phosphorus imbalance:

Questions:
Does anyone here do poorly on some forms of B2, but benefit from other forms?
If you're hypothyroid: Do you tolerate B2 supps? Do you benefit from them?
Can anyone recommend a lab test to evaluate FMN-to-FAD conversion?

Digging up an old one here. @picante when you said you couldn't tolerate FMN, how did you know? And isn't FMN the same as R5P? Did you fare any better after switching?