Re: Vitamin D creating a Magnesium deficiency ?.

If you're taking the secosteroid Vitamin D by mouth, then I'd suggest you do a complex of fat soluble Vitamins too: A, E, D, and K - with fats. The oral version takes a different route in the body than the skin produced D-complexes.

Due to poor farming practices and soil not being replenished, most minerals are low in foods. Processed foods are even worse. A whole food vitamin would be best.

You could try stopping supplementation and re-adding back in each one to see if one of them is causing problems. Many supplements work together. For example: Boron...

"Both human and animal studies demonstrated that boron influenced and interacted with other metabolic factors including calcium, copper, magnesium, nitrogen, glucose, triglyceride, reactive oxygen, and estrogen."

"When boron was increased in human diets, some researchers reported increased estrogen, testosterone, and plasma ionized calcium levels, and decreased calcium excretion as well as decreased effects of the negative impacts of vitamin D and magnesium deficiency previously observed."

Quoted material: http://www.benthamscience.com/open/tompj/articles/V003/SI0001TOMPJ/36TOMPJ.pdf