I learned that I was deficient in magnesium (something that occurs often with individuals who are on the autism spectrum -- usually related to high levels of stress). Magnesium citrate is supposed to be the gentlest form to ingest (more easily digested). The first time I took 2 capsules before bed, it actually made me drowsy and I was able to sleep through the entire night. Since I have been taken 2-3 capsules (each night) for the past 2 years, I have been sleeping like a baby, and have found myself feeling more mellow during the day. If I ever miss a dose, I tend to sleep more lightly, I'll sometimes experience leg cramping/twitching at night, and I'll wake up feeling like I haven't slept. I've also noticed that, if I have completed an intense workout session, my muscles recover faster after taking some magnesium (the night prior). Will always continue purchasing and taking magnesium citrate.