If someone is getting a lot of cramps, they may do well to supplement with calcium. Can you talk a little bit more about this? For most of my life, I was told that cramps were a salt issue and you should eat more salt if you got cramps a lot. Then for a few years I was under the impression that it’s actually a magnesium deficiency, that sodium and calcium help muscles to contract and magnesium and potassium help muscles to relax, so hearing that frequent cramps are related to calcium is very new to me. Can you explain the physiology?

Laura Schoenfeld:  As far as cramps are concerned, there are a lot of different things that can affect cramping, and all of those things that you mentioned can potentially be a factor. All the things you mentioned, like magnesium, potassium, sodium, and calcium, those are all going to be minerals that your body needs to balance fluid, to actually have the muscles contract. I don’t think it’s as simple as that sodium and calcium help the muscles to contract and magnesium and potassium help them relax. I think it’s more complicated, and there’s a lot that goes into the body’s balance of all these electrolytes and making sure that the sodium and potassium channels are going in the right direction. I learned about all this stuff a couple of years ago, so I don’t remember all the details for what cells have what kind of potassium and sodium channels, but I do know that the movement of these two minerals through the cell can make a lot of impact on cell signalling, on neurological function, and on muscle contraction. Magnesium and calcium are other balanced … I guess we would call those macrominerals that can affect cramping and muscle contraction, as well.

Now, the reason why calcium is involved is because calcium is released when the muscles contract, and then it’s kind of sucked back into the cell, and then it can contract again. So if you’re low in calcium, it may actually affect how well the body is able to contract and release that muscle. I’m not saying that calcium is the only thing that is going to cause cramping, but it is something that if someone is very low in calcium, there is a lot of clinical evidence and also anecdotal evidence that calcium supplementation, if necessary, could potentially help with muscle cramping. I wouldn’t just look at calcium, but I’d also look at the sodium, the magnesium, and the potassium. You want to make sure that all the minerals are in balance. You don’t want to just be overly focused on one thing. I know a lot of people, because they think that magnesium is the main mineral involved, they tend to really highly overdose on magnesium supplementation, which can potentially be dangerous if the calcium intake in that person’s diet is quite low. That’s just something to be aware of.