Magnesium is a naturally occurring mineral and is essential for proper functioning of the human body. In fact, more than 300 biochemical processes directly depend on magnesium. While magnesium is the fourth most abundant mineral in the human body, very little actually circulates in the blood or other tissues. Instead, most of the body’s store of magnesium is locked up in the hard outer layer of our bones. We obtain magnesium through the foods we eat, it is absorbed in the small intestine and excess amounts are excreted by the kidneys. In the past few years, there has been an increased interest in the possible role that magnesium may play in preventing and managing conditions like high blood pressure and cardiovascular disease.
Can Magnesium Prevent High Blood Pressure?
One study found data which seems to show that magnesium plays an important role in regulating blood pressure. Additionally, a number of other studies have looked at various nutritional factors and how they contribute to the prevention of high blood pressure. These studies have shown that diets rich in magnesium do seem to have some protective effect and that people who have diets rich in magnesium seem to develop high blood pressure at a lower rate.
However, the real question is: Is it the magnesium in these “magnesium-rich diets” that is providing the apparent protection, or is the observed benefit related simply to the fact that diets rich in magnesium are just plain good for you? To date, this question has no conclusive answer. However, the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, a well-known and respected medical body, feels that the data are strong enough for them to officially state that diets that provide plenty of magnesium are a “positive lifestyle modification for individuals with hypertension.”
Should I Take Oral Magnesium Supplements?
There is no data to support the claim that oral magnesium supplements offer the same benefits as a magnesium-rich diet. Even though magnesium may be beneficial, it may be the case, as it is with other minerals—that how you get magnesium is as important as the magnesium itself. In other words, the human body is very good at digesting real foods and absorbing the vitamins and minerals they contain.
On the other hand, the human body does not seem to be very good at extracting much nutritional benefit from various types of dietary supplements. The ideal way to get the recommended daily allowance (RDA) of magnesium is from natural food sources. For healthy adults, the male RDA is about 420mg and the female RDA is about 320mg, or 360mg during pregnancy.
What Are Good Dietary Sources of Magnesium?
Magnesium is found in a wide variety of healthy, inexpensive foods. Fish and nuts are especially rich in the mineral, 1 ounce of almonds (a small handful) contains about 80mg of magnesium. Potatoes, beans, and low-fat dairy products are also good sources of magnesium, as are certain vegetables such as spinach. As an example, consider the magnesium content of these foods:
- Cooked white fish, 3oz: 90mg
- Cashews, 1oz: 75mg
- Medium baked potato: 50mg
- Plain low-fat yogurt, 8oz: 45mg
- Medium banana: 30mg
- Ready-to-eat pudding, 4oz: 24mg
Each of these foods is also a good source of potassium and calcium, which are helpful in the prevention and management of high blood pressure. A simple rule of thumb for eating a healthy diet is to eat foods that are many different colors. Green peppers, red apples, yellow bananas, brown potatoes, etc.