Bests & Worsts Reviews from Amazon

Contains "Magnesium Oxide" which is one of the least bioavailable types of magnesium for your body - only 4-5%. This is more suited for a laxative than a good way to for your body to supplement needed magnesium. Other forms are much more efficiently absorbed in to your system - like magnesium citrate or malate with a bioavailability rating of 30% or more. They also use a lower bioavailable form of calcium - calcium carbonate (more like an antacid - think Tums). Look for something with calcium citrate. This product should work great if you are constipated and have a lot of stomach acid - which it did for the week I used it. Just "Google" best and worst types of magnesium and then calcium and you'll see for yourself. Wish I had done a more thorough research before I purchased it just because it was rated #1.