When it comes to taking multivitamins or other dietary supplements, the supplement industry reps will assert that the more you take, the better.
You can partially thank the work of Linus Pauling and his supporters, who made it their mission to spread fraudulent work regarding the miracle works of dietary supplements and vitamins, especially vitamin C. You can also thank the Dietary Supplement Health and Education Act of 1994, which exempts the supplements from undergoing FDA regulation and allows for labels to claim things like "supports bone health" or "maintains healthy immune system."
But nutrition experts and the entire scientific community would argue otherwise.
For the general population, the vitamins and minerals the body needs are typically already found in a well-balanced diet. Sure, there are exceptions with those who may be deficient in certain vitamins or minerals, but the rest of us need not add multivitamins and other supplements to our daily routine to keep healthy. And magnesium, a mineral found in many foods, is no exception.
The mineral is responsible for controlling a number functions in your body: it helps maintain normal nerve and muscle function; it keeps a regular heartbeat; it regulates blood glucose levels; and helps keep bones strong. And just how are you getting this mineral, you ask?
Most dietary magnesium comes from dark green, leafy vegetables, but other foods also contain the mineral: bananas, avocados, nuts, peas and beans, soy products, whole grains, and milk. And if your diet includes even a couple of the above, chances are you are getting enough magnesium to meet your needs. If you're not eating any of the above, you should start, and for more than one reason.
Although magnesium is being studied for its role in preventing or managing high blood pressure, heart disease, and diabetes, health experts do not recommend taking magnesium supplements. In fact, according to ACSH friend Paul Offit's poignant article in The Atlantic titled 'The Vitamin Myth: Why We Think We Need Vitamins," taking on too much magnesium (or any mineral or vitamin for that matter) can have negative impacts. Based on a study from the University of Minnesota in 2011, researchers found that people who took supplemental vitamins, magnesium, zinc, copper and iron died at rates higher than those who didn't.
It's important to note that, in rare cases, a magnesium deficiency can occur. Diets high in protein, calcium, or vitamin D could increase the need for magnesium. A magnesium deficiency can also occur in people who abuse alcohol.
In hospital settings, patents on Lasix, or who receive a potassium boost should also be checked for the levels of magnesium in the body, as those may also be reduced by diuretics. For the rest of us, taking magnesium supplements on top of what we already get from our diet isn't necessary; the benefit is nil.