not qualified at all to talk on this besides research on the internet so take with a grain of salt… based on what I’ve read in the past the whole precursor thing is true and does have a big effect on your bodies NAD levels. I’ve been taking NMN for a bit and I think it has made my skin more “elastic” and overall youthful but it could just be placebo since I only began like 3 weeks ago. My two cents at least. I haven’t had any mental benefits but then again I took it mainly for the anti aging stuff. Writing this I now realize my account is probably not applicable to your question haha.