I read from the same sources that indicate NAD+ is a "possible treatment" that e.g. L-carintine is also a "possible treatment" with the same mild success rate (20% max over placebo). The L-carintine study was not double blind though.
It's super easy to get people to buy "nutrients" and "supplements" that their bodies don't actually need. Most people have no clue how cellular respiration works nor do they have enough knowledge of biology to know that in 99.9% of cells, there's no "deficiencies" that need to be corrected. So when scienists publish a study saying, for instance, "CoQ10 may decrease the risk of such-and-such disease" people read that as "CoQ10 has been proven to stop you from getting such-and-such disease". In reality your body is producing normal levels of CoQ10, or ubiquitin, or NAD+, or whatever the fuck it is, and the excess you supplement with goes to waste.
Most "exotic" nutrients like choline, vitamins, coenzymes, NAD+/FAD+, etc are abundant in a healthy diet as well as being produced in the body. There is simply no need for supplementation unless you are very ill (systemic infections) or genetically impossible of making/disposing of them (and this usually results in death because your cells don't produce energy).
The reasons these nutrients are "advertised and popular" is the same reason those stupid Q-ray bracelets or penis enlargement pills work. Lots of people are too proud to admit they spent money on a placebo. Confirmation bias and all that. Moreover people use the lack of "bad" evidence as proof that it *must* be working (If it didn't work, why is it still sold?). The reason is simply because the FTC/FDA hasn't stepped in and said "stop it". Most of these supplements are marketed as supplements, meaning they don't have to show a positive effect. Same department as homeopathy.
If you have CFS you should see a doctor. Don't treat yourself with "cures" based off a single double blind study.
