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NAD+ / Niagen/Niacin for undermethylation/CFS?

Hi I was wondering if someone could tell me in plain English if Niagen/Niacin supplement is good for undermethylators. I am undermethylator plus CFS plus "pure" OCD. Seems that NAD+ is a methyl donor (or I may have gotten it wrong, please correct me), while excess Niacin (B3) uses up methyl groups. At least that is what my read is from looking at various threads here. One such thread is here - http://forums.phoenixrising.me/index.php?threads/anyone-trying-niagen.30636/.

So it would be nice if someone with similar symptoms has experienced definitive - positive or negative - outcome after trying Niacin/Niagen supps. Thoughts?


Moderator Resource
Southern California
@kkrathi - I'm a little confused when you write "niagen/niacin" together, because they are different things. Niacin does slow down methylation - it makes me tired if I take it during the day but I take it at night because it helps me sleep. It's supposed to stimulate GABA receptors so that's why I think it helps with sleep and many people here use it when they get overmethylation symptoms.

Re Niagen - I just don't know. I considered it at one time but it's very expensive so decided against it.

Several years ago I took NADH. I had to take 20 mg. a day to get an effect, but it did boost my energy a lot. Unfortunately, it only lasted for about 10 days and then it just stopped helping.


Senior Member
NAD+ is not a methyl donor. It is used extensively in the Citric Acid Cyle, and in many people it gives them energy and/or causes insomnia. But not through methylation.

If you want more methyl donors, I would try methylfolate, methylcobalamin, trimethylglycine (TMG), phosphatidylcholine, and possibly curcuminoids (Not all at once!).

Best of luck.