Many Americans don't get enough magnesium in their diets. Before you reach for a supplement, though, you should know that just a few servings of magnesium-rich foods a day can meet your need for this important nutrient.

Nuts, seeds, whole grains, beans, leafy vegetables, milk, yogurt and fortified foods are good sources. One ounce of almonds contains 20% of the daily magnesium an adult needs. Even water (tap, mineral or bottled) can provide magnesium. Some laxatives and antacids also contain magnesium.

Why is magnesium important? Magnesium plays many crucial roles in the body, such as supporting muscle and nerve function and energy production.

Low magnesium levels usually don't cause symptoms. However, chronically low levels can increase the risk of high blood pressure, heart disease, type 2 diabetes and osteoporosis.

Too much magnesium from foods isn't a concern for healthy adults. However, the same can't be said for supplements. High doses of magnesium from supplements or medications can cause nausea, abdominal cramping and diarrhea.

In addition, the magnesium in supplements can interact with some types of antibiotics and other medicines. Check with your doctor or pharmacist if you're considering magnesium supplements, especially if you routinely use magnesium-containing antacids or laxatives.