@retiredphil I will challenge taking magnesium without talking to your doctor first. Magnesium can be hard on your kidneys, and many, many seniors have kidney decline if not into a stage of kidney failure. Also, magnesium can cause slow heart rate, that is called tackycardia and I can have this several times on any day, like down into to 40's. Pre PMR I had it all the time. Lastly magnesium can slow blood clotting as well as cause problems if you already have a heart rhythm problem.
True that we may benefit from magnesium, but I would encourage people to ask their doctor about going on any supplement first, just in case it's not for you.