Magnesium: Why You Need More
Most of us don't get enough of this precious mineral from food, and a deficiency can lead to numerous health issues, from anxiety to diabetes. Here's how to use supplements
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Magnesium doesn’t get as much attention as calcium, which is added to many foods, but according to the National Institutes of Health, most Americans lack sufficient amounts of this key mineral. And that’s not good, because magnesium is required for more than 300 different ongoing processes in the human body.

Some of the mineral’s most important functions include promoting bone, nerve and muscle health; helping regulate blood pressure and blood sugar; enabling energy production; and ensuring normal heart rhythm. Lack of magnesium can be an underlying factor in anxiety, sleeplessness, osteoporosis, muscle cramps, PMS, headaches (including migraines), fibromyalgia, asthma, and heart disease.
Among the many studies showing the value of magnesium, a recent one, published in the journal Nutrients, found that getting the daily recommended amount of magnesium reduced the odds of insulin resistance-a precursor to diabetes and heart disease-by a whopping 71 percent.
Why We Run Short
The government recommends that women get 310 mg of magnesium daily up to age 30, and then 320 mg afterwards; it’s suggested that men consume 400 mg daily up to age 30, and then 420 mg afterwards. Unfortunately, the mineral typically isn’t abundant in our diets. For example, common food sources of magnesium, include:
- 1 oz dark chocolate: 95 mg
- 1 oz. roasted pumpkin seeds: 81 mg
- 1 oz. dry roasted almonds: 80 mg
- ½ cup cooked spinach: 78 mg
- ½ cup brown rice, cooked: 42 mg
- ½ cup Swiss chard, boiled: 75 mg
- ½ cup cooked black beans: 60 mg
- 1 cup cubed avocado: 44 mg
- 1 medium banana: 32 mg
- 3 oz. salmon: 26 mg
- 3 oz. chicken breast, roasted: 24 mg
- 3 oz. lean ground beef: 20 mg
- ½ cup broccoli, cooked: 12 mg
- 1 medium apple: 9 mg
- 1 medium raw carrot: 7 mg
Some common drugs deplete magnesium. These include birth control pills, heartburn drugs (proton pump inhibitors), chemotherapy drugs, corticosteroids, diuretics for high blood pressure, insulin for diabetes, asthma drugs, digitalis for the heart, and some antibiotics.
How to Get Enough
In addition to making sure you get the daily requirement of approximately 400 mg, there is another point to consider. Magnesium and calcium work together, so we need a balance of the two, optimally a 2:1 or 1:1 ratio of calcium to magnesium. Most multis contain a 2:1 ratio of these minerals, but not a full day’s serving. For your personal needs, take dietary sources into account, and aim to get at least 320-400 mg of magnesium daily-or more to maintain a healthy magnesium/calcium ratio (especially if you take extra calcium), or if you have symptoms of a shortage.
Understanding Food Labels
Food labels usually list magnesium content as “%DV,” meaning “percent of Daily Value.” The FDA has set 400 mg daily as the DV, so if a food contains 10% DV, it provides 40 mg of magnesium.
Supplement Shopping Tips
Supplements contain magnesium bound to another substance, because it’s impossible to package pure magnesium. Amino acid chelates (magnesium bound to amino acids such as magnesium glycinate), and magnesium citrate, lactate, and chloride are considered well absorbed forms of the mineral. If you take more than your body can absorb at one time, loose stools are a symptom. You can also absorb magnesium through the skin by adding magnesium salts, flakes, or powder to your bath-a relaxing antidote to stress.
Alzheimer’s Treatment
Alzheimer’s disease is incurable, but in animal research, its symptoms have improved with Magtein, a special form of magnesium that’s designed to be utilized by the central nervous system, including the brain and spinal cord. These parts of the human body don’t usually absorb magnesium well.
To determine bioavailability, researchers gave animals different forms of magnesium and then measured levels of the mineral in cerebrospinal fluid. Only Magtein significantly raised these levels. In another study, researchers performed memory tests before and after animals were given magnesium in various forms. Only those who received Magtein showed a significant improvement.
Another type of study was done with mice that are bred to have 15 times the normal risk for Alzheimer’s. In this group, the animals given Magtein lived longer than usual and appeared to have improved memory during the end stages of Alzheimer’s.
Products that contain Magtein may have names that imply cognitive, neurological, or brain health, or may include “Magtein” in the product name. Magtein is also called magnesium L-threonate. Supplement Facts sections of product labels usually state that one serving contains 2,000 mg, or 2 g, of Magtein magnesium L-threonate and 144 mg of magnesium. Such supplements are designed for brain health, not as complete sources of dietary magnesium.

Natural VitalityNatural Calm Plus Calcium blends a highly bioavailable form of magnesium with just the right amount of calcium.

NutraMarks, Inc. Life-floPure Magnesium Flakes are magnesium chloride crystals from the Netherlands; add to a bath or foot soak.

Source NaturalsMagtein provides magnesium L-threonate, shown to deliver more magnesium to the brain.