I'm amazed nobody has mentioned magnesium yet. I was told that by my naturopath a few years ago, and it definitely works. I take a magnesium supplement called Bio Magnesium which also has calcium, vitamin B6, vitamin D3 and manganese. It's made in Australia by Blackmores, but there are probably equivalent products in other countries.

One thing that is worth mentioning is that calcium and magnesium work together, and an over supply of one can cause a deficiency in the other, so they need to be taken together in the right balance.

Sometimes I get lazy and forget to take them for a while, until another leg cramp reminds me, and I start taking them again. If I happen to have run out, I will keep getting leg cramps until I start on them again, then the effect is very quick - within 24 hours I'm back to normal. So it's obvious to me that they make a difference. It's been a few months now since I last woke up with a cramp.

Wesley, it's interesting what you said about getting cramps while you're dreaming. I can see why that would be. I think when you are dreaming, you tense up muscles - as if you were actually doing the thing you are dreaming you are doing - if you get my meaning. I've caught myself tensing up a muscle as part of a dream and then waking up because it has caused a cramp - particularly in my case if I extend my foot and curl the instep up a bit, it will cramp (if I haven't been taking my magnesium) and the only way to get rid of that is to slowly flex my foot the other way and stretch the muscle.