Unfortunately, these " NOW Magnesium Malate 1000mg,180 Tablets " don't seem to work for us. My usual source of Magnesium had been from Magnesium Citrate via " Natural Vitality Natural Calm Magnesium Anti stress, Original, 16 oz ". But, I was slightly worried about a reaction to the citrate portion of that, and preparing it has gotten somewhat annoying over the years (heating up the water in the microwave and stirring the powder in until it dissolves [gasp]), so I thought I'd try a pill form. Of the pills I found, Magnesium Malate seemed the best bet for absorption, and NOW formulations don't have additional crud added into them. So, this is what I chose. But, after taking these for about six weeks, both of us started having more and more foot cramps at night. It got to the point where it was happening every night. So, we went back to the "Natural Calm" and the foot cramps went away immediately. I don't know how well these work for other people, but since they aren't working for us, I can only rate them at 1 star out of 5