Supplement Safely with Magnesium
If you feel that you are one of the majority of Americans who don't get enough magnesium from their diets, it may make sense to take a daily supplement, but always check with your doctor before taking any supplements.
If you decide to get your magnesium level checked, ask your doctor for a magnesium red blood cell (RBC-Mg) test. It measures the magnesium that is inside cells. It's a more accurate measure of magnesium than the standard serum magnesium test. An optimal RBC-Mg level is more than 5.5 mg/dL.
The test isn't essential. If you generally are healthy, you can't go wrong with extra magnesium. The Institute of Medicine advises women 31 years old and older to get 320 mg of magnesium daily. For men, the recommended amount is 420 mg. These are conservative estimates based on your minimal needs. What I recommend...
Multiply your weight in pounds by 3 mg to determine the optimal dose.
Example: A 140-pound woman would take 420 mg of magnesium. During times of stress, when your need for magnesium is higher, multiply your weight by five instead of three. Keep taking the higher dose until things calm down again. You will start to feel the benefits within a few days.
When you're shopping for supplements, look for products that end with "ate"-magnesium glycinate, taurate, malate, etc. These forms are readily absorbed into the blood stream and less likely to cause diarrhea.