I had a similar beneficial response from magnesium supplements. I've always had a constellation of health issues, probably genetic, and constant anxiety and was one of the most detrimental to just getting on in life, and later I had much trouble sleeping, either not being able to get to sleep or not sleeping for very long.

I researched nutrition and genetics for many years and tried a number of supplements based on testing hypotheses I would come up with. I generally used the Linus Pauling Foundation guidance on RDA as they are annotaed with a history of how RDAs came about, whether the official RDA is optimal or not, various caveats etc.

Magnesium had a profound effect after I researched bioavailability and tried some of the organic forms. The two main ones that worked were magnesium glycinate and citrate.

I've also went through a phase of having a strong beneficial effect from high dose vitamin B12 (methyl form), which initially caused what I felt was deeper sleep but also intense nightmares; this effect wore off after a while and that might be due to correction of a deficiency.