Magnesium deficiency increases the risk for colorectal cancer

A large study that appears in September's American Journal of Clinical Nutrition shows that magnesium deficiency can increase the risk of colorectal cancer. In addition, it introduces new evidence that a specific genetic polymorphism could also increase or decrease our colorectal cancer risk depending on calcium:magnesium intake ratio. The highest calcium intake coupled with the lowest magnesium intake produced the highest colorectal cancer risk among 4623 subjects.

Bonnie - this is one the of most comprehensive studies to explain why too much calcium and too little magnesium and vitamin D is damaging to your health. I wish the Dairy Council would study this at length!

The researchers explain that magnesium counters the action of calcium in many physiologic activities, just like potassium does with sodium. Calcium and magnesium compete for intestinal absorption, so if one's calcium intake is too high, it makes absorbing magnesium much tougher (this is why many of my new clients go off of supplemental calcium for a while initially...to give the body a chance to balance the cal:mag ratio). Hence, a high calcium intake with low magnesium intake may exaggerate colorectal cancer risk.

In the United States, this issue is magnified because while our magnesium intake does not differ from many other parts of the world, our calcium intake is much higher than most of the world.

The researchers go on to say that the largest single contributor to magnesium intake is supplemental magnesium. They comment that getting adequate magnesium through food or other means is difficult.

The researchers were very clear in saying that the risk of colorectal adenoma decreased with an increasing total intake of magnesium in every model they studied.

Another very important discovery was that the higher the vitamin D levels, the higher the magnesium levels were as well. The only scenario where total calcium intake was associated with lower colorectal cancer risk was when vitamin D and magnesium levels were high in comparison to calcium intake.

Furthermore, the researchers suggest that magnesium deficiency may cause calcium deficiency (translation: if you are magnesium deficient, all that calcium you are taking is either excreted from your body or is calcifying in soft tissue). This can cause irregularities in many biological activities, such as inflammation, DNA repair, cell proliferation, differentiation, angiogenesis, apoptosis, insulin resistance, and carcinogenesis.