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Magnesium - The Most Underrated Supplement

Magnesium is an essential mineral that is a requirement for a few important processes in the human body. Specifically, there are over 300 biochemical reactions in the human body for which magnesium is required. There are a number of people that get the required amount of magnesium strictly by eating a well-balanced diet. For others, deficiency in this crucial element may be a health issue in the making.

Magnesium Deficiency

It is estimated that 60% of people do not get enough magnesium through their diet. Magnesium deficiency has many potential implications. Symptoms of a moderate or severe magnesium deficiency can include muscle cramps, personality changes, tremors, abnormal heart rhythms, or loss of appetite. However, people with a mild magnesium deficiency may have no visible signs or symptoms. What makes diagnosing magnesium deficiency even more difficult to diagnose is how it is stored in the body.

On average, the body contains anywhere from 21 to 28 grams of magnesium. More than half of the magnesium in the body is stored in the bones. Less than 1% of the magnesium in the body is contained in the blood. Therefore, it is difficult to determine how much total magnesium any one individual has at a given moment. To make matters more difficult, when the magnesium levels in the blood become too low, the body will remove the magnesium from the bone and put it in the bloodstream.

Magnesium is important for maintaining levels of other electrolytes, especially potassium. In fact, potassium levels are actually dependent on the amount of magnesium available in the blood stream. So if your magnesium levels are low, taking potassium will not raise your levels of potassium. This means that if your potassium levels are low, you may need both magnesium and potassium to get your potassium levels back to normal.

Magnesium is also required for maintaining bone health. Low magnesium can cause low parathyroid hormone levels and low calcium levels, both of which are necessary to maintain bone density. Therefore, magnesium supplementation may be necessary in patients with osteoporosis or those trying to prevent developing osteoporosis as they get older.

What Causes Magnesium Deficiency

Magnesium deficiency can be caused by inadequate dietary intake, medications, and alcohol use. Alcohol use causes the kidneys to eliminate more magnesium in the urine. In addition, there are several medical conditions where magnesium deficiency is common.

Medications that Cause Magnesium Deficiency

The most common cause of magnesium deficiency, believe it or not, is not inadequate dietary intake. In fact, the most common cause of magnesium deficiency is medications. Specifically, magnesium deficiency is caused by two classes of diuretic medications (or "water pills") that are commonly prescribed. The medications cause the kidneys to deplete magnesium in the bloodstream by eliminating it in the urine.

One class of medications that cause magnesium deficiency is thiazide diuretics. Thiazide diuretics are commonly prescribed with other medications for high blood pressure (hypertension). One of the most commonly prescribed thiazide diuretic is hydrochlorothiazide, or HCTZ. While there's no evidence that all people taking thiazide diuretics should also take magnesium supplements, it may be a good idea to check magnesium levels for these patients.

The other class of medications that causes magnesium deficiency is loop diuretics. Loop diuretics are commonly prescribed for patients with a heart condition known as congestive heart failure (CHF). Furosemide and torsemide are the most commonly prescribed loop diuretics. Patients taking furosemide or torsemide should have their magnesium and potassium levels monitored closely for this reason.

Diseases and Conditions Associated with Magnesium Deficiency

Magnesium deficiency is known to be associated with several different medical conditions. It is also thought to play a significant role in a few others. This does not necessarily mean that magnesium deficiency causes these diseases, just that scientists have identified a correlation.

When people suffer from a myocardial infarction (heart attack), they also suffer from a temporary magnesium deficiency. People with type 2 diabetes commonly are deficient in magnesium. Magnesium deficiency is also seen in many different heart conditions and abnormal heart rhythms. Patients with Alzheimer's disease are known to be deficient in magnesium. People with sleep apnea are more likely to have low magnesium levels. Magnesium has also been associated with psychiatric diseases such as depression and ADHD.

How to Increase Magnesium Levels

The best way to increase magnesium levels is through the diet by eating foods that are rich in magnesium. However, for people who are deficient in magnesium as a result of medications will likely need to supplement their dietary intake. Simply eating foods with more magnesium will likely not be enough for these people.

Magnesium is commonly found it a number of multivitamin and over-the-counter supplements available almost anywhere. Patients who think they may suffer from magnesium deficiency should schedule an appointment with their doctor to determine if they require supplementation. However, there are several different forms of magnesium that are available over-the-counter and not all of them are equally effective.

The most commonly available forms of magnesium include magnesium oxide, magnesium hydroxide, magnesium sulfate, and magnesium citrate. These forms of magnesium supplementation are all likely to cause diarrhea even in low doses. These forms of magnesium are actually commonly prescribed or used for that very purpose - to ease constipation. One form of magnesium that does not usually cause diarrhea is magnesium glycinate. This form of magnesium may be harder to find, but provides supplemental magnesium with fewer bowel issues.

The recommended daily allowance of magnesium is 420mg for men and 330mg for women. Some doctors and scientists suggest that people should consume more, up to 1,000mg per day. Most supplement formulations come in 200mg and 100mg doses.

Foods High in Magnesium

If you're intent on increasing the amount of magnesium in your diet, there are a number of foods you can eat to raise your magnesium levels. Foods high in magnesium include:

  • Spinach, 157mg per cup

  • Pumpkin seeds, 156mg per 1 oz.

  • Lima beans, 126mg per cup

  • Black beans, 120mg per cup

  • Tuna, 109mg per 6 oz.

  • Brown rice, 86mg per cup

  • Almonds, 77mg per 1 oz.

  • Cashews, 74mg per 1 oz.

  • Peanuts, 63mg per 2 oz.

  • Dark chocolate, 65mg per 1 oz.

  • Avocados, 58mg per avocado

  • Bananas, 41mg per cup

Ultimately, you should work with your doctor to determine if you need more magnesium. For people with kidney disease, magnesium and other electrolytes should be monitored closely.


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