Can Coffee Deplete Magnesium?

Minerals such as magnesium play an important role in the human body, even though you only need a relatively small amount of them for optimum health -- less than half a gram per day. If you drink coffee, you may not absorb magnesium efficiently, possibly leading to a magnesium deficiency. This can be counteracted by consuming more magnesium each day, but you should talk to your doctor before taking any sort of magnesium supplement.

A cup of coffee next to a computer. (Image: Stockbyte/Stockbyte/Getty Images)

Magnesium and Health

Your body contains approximately 25 grams of magnesium, most of which is found in the skeleton. The majority of the remaining magnesium can be found in your muscles and inside of other cells. Magnesium is important for converting carbohydrates and fats into forms of energy that cells can use, and it also is critical for making new DNA and proteins. Structurally, magnesium is important for the health of your bones and cells. It also regulates the function of muscles and nerves because it affects the levels of other minerals inside of your cells.

Coffee and Magnesium Levels

Drinking coffee can affect the levels of magnesium in your body. When you drink coffee, your intestinal absorption of magnesium decreases. Although coffee does not directly deplete magnesium from your body, the decreased absorption of magnesium can cause your body to gradually lose magnesium, potentially resulting in a magnesium deficiency. The more coffee you drink, the less magnesium your intestines can absorb. This becomes more important as you get older, as magnesium absorption typically decreases with age.

Signs of Magnesium Deficiency

A lack of magnesium can reduce the strength of your bones and also lead to a disruption of the other cellular processes that require magnesium. In addition, low magnesium levels can reduce the amount of calcium in your body. Other signs of a magnesium deficiency include agitation, anxiety, rapid breathing, muscle tremors or spasms, irregular heart rhythm, low blood pressure, trouble sleeping, poor nail growth, nausea and vomiting, confusion and seizures.

Treatment

If you drink coffee and are worried about a magnesium deficiency, the simplest treatment is to eat more foods that contain magnesium. Legumes, whole grains, Brazil nuts, soybean flour, molasses, green leafy vegetables, almonds, squash, pumpkin seeds, black walnuts and cashews are all good sources of magnesium. You can also get magnesium from peanuts, oat flour, bran, bananas and baked potatoes with the skin on them. Magnesium supplements can also be taken to correct a magnesium deficiency, but you should talk to your doctor before taking magnesium or any other sort of supplement.