Bests & Worsts Reviews from Amazon

I had been taking a different magnesium citrate supplement. It was 3 large capsules to get 400mg. Then I got this one. One medium sized capsule to get 400mg. Hmmm.... Is that possible? So I did some research. Magnesium citrate contains about 20% elemental magnesium. You can check this anywhere. So, in order to get 400mg of elemental magnesium, which is what you want, you need to take in 2,000mg of magnesium citrate. If a capsule has 2,000mg of magnesium citrate, it must weigh more than 2000mg, because there is the weight of the empty capsule, too. I weighed all of the capsules, minus the bottle, and divided by 180 (number of capsules). Each capsule weighed 730mg. A capsule that weighs 730 mg cannot have 2000mg of magnesium citrate in it. I think what they are doing is selling you 400mg of magnesium citrate, not 400mg of actual magnesium. I am sending them back. --Former engineering lab tech PS - the only certification on the label is "GMP", which stands for "good manufacturing practices". This is a certification which means that they follow every instruction carefully when creating this product. It is not a certification of how good those instructions are, or the quality of the product. PS - Why don't we just take capsules with pure magnesium in them? Because our bodies can't digest them.