Can You Take Too Much Magnesium?

A recent question from one of my 10am clients, Angie:

“Can you take too much magnesium?”

Answer:

Yes. Typically, you will get loose stools and/or stomach cramps. Those are some of the first signs that you’ve taken too much. Other than that, magnesium doesn’t tend to cause issues, even at higher doses, unless taken for a very long time. 

I’ve personally worked up to 3,000 milligrams a day for a while, just to see how I would feel, without issue. Most people benefit from 400-800 milligrams a day. You can ask your doctor for a “Magnesium RBC” test to see where your levels currently sit. The RBC test measures magnesium in your red blood cells, which is a more reliable indicator of systemic magnesium saturation compared to a serum magnesium blood test.

The worst form of magnesium to take is magnesium oxide. Your body absorbs very little of it. Yet, it’s cheap to make, so it’s very common. Magnesium citrate has the worst stool-softening properties, so I usually don’t recommend it either. I sell magnesium glycinate at the gym because it is gentle on the stomach and includes the amino acid glycine, which is very calming for the muscles and nervous system. Magnesium chloride is also very good and cheap, but mainly comes as “flakes” and doesn’t taste great no matter what you mix with it. Magnesium threonate is the only form of magnesium that crosses the blood-brain barrier, which makes it very beneficial.