What is magnesium?

Magnesium, like calcium, is most comfortable in nature when it gives up two electrons and takes on a double positive charge (Mg2+). Therefore, like calcium, you may be thinking that magnesium may provide at least some of its function by electrically interacting with other substances. This is certainly the case as is discussed next.


What foods provide magnesium?

Magnesium is found in a variety of foods; better sources include whole grain cereals, nuts, legumes, spices, seafood, coffee, tea, and cocoa. Certain processing techniques such as the milling of wheat and the polishing of rice may result in significant losses of magnesium from grains and other foods. Also, some magnesium can dissolve into cooking water during boiling, which results in some cooking loss as well.

What are the recommendations for magnesium intake?

The RDA for magnesium varies depending on age gender and condition. For instance, the RDA for 19 to 30 year old women and men is 310 and 400 mg. However after the age of 30 the RDA bumps up to 320 and 420 mg, respectively. Meanwhile the Daily Value for magnesium is 420mg. 


What does magnesium do in the body?

Roughly 60 percent of the magnesium in the body is located in the bones. The remaining magnesium is found mostly in muscle and other tissue. Only a small percentage of magnesium is found in extracellular fluid. Magnesium in the bone can interact with calcium and phosphates to help increase the integrity of bones. The bones also serve as a reservoir or storage site for magnesium.


One thing that magnesium seems to do is to interact with the phosphates of ATP. This adds stability to ATP and improves the ability of ATP to power cell operations. Many chemical reactions require the splitting of an ATP molecule to release the energy necessary to drive the reaction or cell activity. In fact, magnesium seems to be a vital factor in the proper functioning of more than 300 chemical reaction systems.


What happens if too little or too much magnesium is consumed?

Magnesium absorption from the digestive tract is fair (25 to 50 percent) with several factors being able to influence this efficiency. For example, a low body magnesium status results in a higher percentage of absorption. On the other hand, a high magnesium diet or excessive dietary calcium, phosphate, or phytate can decrease the efficiency of magnesium absorption.


Subtle alterations in blood magnesium content can affect the release of parathyroid hormone (PTH) and its activity. Further, a magnesium deficiency can negatively influence the ability of the cell membranes to maintain optimal sodium and potassium concentration differences across membranes. This is largely because magnesium is needed to stabilize ATP, which is the power source for pumping these ions across cell membranes. Thus, the proper function of excitable and other cells is jeopardized during magnesium deficiency. On the other hand, toxicity induced by a high dietary intake of magnesium can be thwarted by appropriately functioning kidneys.