A likely cause for headaches is calcium rigor, which is caused by magnesium deficiency. Body can always take calcium from bones, even on those days when none is coming with diet, but magnesium is a totally different story. Calcium and magnesium have to be taken together. If you look at the calcium supplements, they are almost always mixed with magnesium.
You should take about 1000 mg of magnesium per day. And also 1000 mg of calcium.
Do an internet search for "calcium rigor" and "magnesium deficiency". Body has over 350 magnesium metalloenzymes, if you do not have elemental magnesium in your bloodstream, the enzymatic precursors cannot form functional enzymes.
Should you decide to start supplementing with magnesium, make sure it is NOT oxide. Magnesium oxide is the cheapest form of a commercial supplement, but it is also a powerful laxative. Chelated or citrate is the best.
I have two websites where this is described in detail, but I cannot post URLs here, which I find a strange requirement, as I do not sell anything there, not even Google AdSense.
If you want, send me a private message, I'll reply and your headaches will be history.
P.S. I understand you Brits write "rigour", so adjust your search accordingly.
P.S.2>>> DO NOT take vitamin C with calcium and no vit C for an hour after you take calcium. No copper supplements with vit C either.
::hth
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