@viv1953 You can ask your doctor for a blood test. I started taking 250-300mg/day of magnesium glycinate to help relax my muscles for better sleep and because I read it can help with osteoporosis by balancing your calcium and activating vitamin D. (The RDA for magnesium for women is from 310-320mg/day for most adult women.)

One positive side effect I noted was that previously I needed to take Miralax every day to avoid constipation. Once I started taking magnesium every day, that was no longer an issue for me.