Too Much Calcium & Not Enough Magnesium

Both calcium and magnesium are abundant minerals in the body involved in bone structure, proper nerve and muscle function, and blood pressure regulation. These minerals also compete as messengers in the regulation of cell proliferation and inflammation. A disproportionate ratio of the two minerals can impact the ability of both to function properly.

Relationship

Calcium and magnesium are regulated by a dual negative feedback system, through competition for intestinal absorption and renal reabsorption. These minerals also compete for binding sites in cells. According to a study published in the "American Journal of Epidemiology" in 2010, these two minerals are most antagonistic when intake of one is much higher than the other.

Disease Risk

Researchers from Vanderbilt University published the results of a study in 2011 in the peer-reviewed online journal "PLoS ONE" examining the relationship between calcium, magnesium and risk of prostate cancer among 494 males participating in the Nashville Men's Health Study. Researchers found that blood calcium levels were not associated with high-grade prostate cancer risk by itself. However, when magnesium levels were taken into account, researchers found men with lower magnesium levels and those with higher calcium to magnesium ratios did have increased risk. Scientists believe this study suggests the interaction between magnesium and calcium plays a role in the development and progression of this disease.

Calcium

The recommended intake of calcium for adults is between 1,000 mg to 1,300 mg depending on gender, age, and pregnancy status to ensure healthy bone structure. The Institute of Medicine has also set a tolerable upper limit intake at around 2,000 to 3,000 mg depending on age. According to Linus Pauling Institute, intakes above this amount could result in nausea, vomiting constipation, loss of appetite, abdominal pain, thirst and frequent urination. There is no documented case of toxicity resulting from consumption of food, only from taking excess amounts of calcium supplements.

Magnesium

Daily recommended intake for magnesium is between 310 to 420 mg based on sex, age and pregnancy. It is found in a variety of foods including whole grains, legumes, nuts, and green leafy vegetables. Refined grains like white bread and pasta have minimum amounts since the magnesium-rich germ and brand are removed during processing. Early signs of magnesium deficiency include loss of appetite, gastrointestinal distress, weakness, fatigue, tingling, muscle contractions and cramps, and eventually seizures.