Is low magnesium wearing you down?

In the ongoing battle to gain from our society’s scientific illiteracy, Dr. Oz has nocked another arrow. This time, he as the cure for all fatigue. I hope he’s got this right because this is one of the most common and most difficult problems to treat.

Fatigue is a tough one. Everyone has experienced fatigue at some point, and as a physician, part of my job is to figure out just what someone means when they say, “I’m tired.” One of the first distinctions is between “fatigue” and “sleepiness”. Sleepiness is often caused by sleep disorders such as restless leg syndrome or sleep apnea. Fatigue is more vague and varied. It’s also fairly miserable.

It’s rare to find a single cause (and therefore a single cure) for fatigue. Sometimes you get lucky and find a thyroid disorder or other simple problem, but more often it’s a mixture of factors such as overwork, depression, and stress. And it’s not always pathologic. If someone tells me that they’re fatigued, and they work 50 hours a week and are raising kids and taking care of parents, there’s not much to do except try to find ways to change circumstances or cope with fatigue.

But Dr. Oz breaks it down much more simply. He starts his little video with his usual medicine show gimmicks, this time a tray of grey powder. He runs his hands through it and dumps it out to reveal the word “MAGNESIUM”. Chemists in the audience may have displayed a bit of anxiety, as elemental magnesium has a tendency to ignite and explode, but when it’s powdered you sometimes get lucky and a layer of oxidation reduces (!) the risk. Or maybe it wasn’t elemental magnesium at all. Who knows?

After playing with magic Boom Powder, he explains his surprise on having learned that about three-quarters of Americans are magnesium-deficient. I was surprised too, given it’s not remotely true. A search of the literature confirms only what most doctors know, that many patients in hospitals are mag-deficient, usually due to medications or illness.

I’m not sure where he gets his “three-quarters” number, but I did find one study that asked people to recall recent meals, and found that 68% consumed less than the US RDA recommended amount of magnesium in their meals. They didn’t actually use food diaries or magnesium levels. To go from a survey of recalled meals to a hard figure on actual mineral deficiency isn’t right—it’s not even wrong. I found little else in the literature to support the assertion of wide-spread mag-deficiency.

But Oz is pretty sure about it. According to him,”low energy” is the strongest indication of low magnesium. This boring assertion is also void of meaning. What is “low energy”? Is it a subjective feeling? An objective measurement? And how do we know that this thing is at all connected to magnesium? (Hint: we don’t.)

But Oz knows that nothing proves a crazy statement like a good testimonial. He explains that symptoms of magnesium deficiency are irritability, anxiety, and lethargy. Then he has a woman describe an episode of just these feelings, one that sounds to my medical ear like a panic attack. He plays with another toy, this time a water tank and a whoopie cushion (if you have the stomach, go see for yourself). The side show tricks aren’t just boring, they’re senseless and distracting. The guest is describing a real, treatable problem and is being fed fake solutions.

He shows a clip of another woman who says:

Dr Oz, I have five kids and I’m exhausted from the minute I get up to the moment I go to sleep. I need you to help me get my energy back!

You can guess what the answer is. My answer is a bit different. The busy mom has a crazy life. She works hard. Working hard is exhausting. The cure for that sort of exhaustion is rest. Sometimes improving rest and work habits is feasible, sometimes not, but the cure isn’t valium, adderall, or magnesium. It’s empathy, compassion, and changes to families and societies that help improve our quality of life. And perhaps the judicious use of some medications.

Selling a cure based on imaginary evidence isn’t just irresponsible, it’s immoral and goes a century of medical ethics. It’s behavior unsuited to a good physician, but probably a step up from your average carney.

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  1. A healthy diet with a variety of vegetables and legumes will provide us with what we need. My fear is that many people with normal magnesium levels will see this and start supplementing themselves to high levels (especially people with kidney disease who can become magnesium toxic with even good ol’ Milk of Magnesia).

    Here’s a link to some responsible information on magnesium and magnesium toxicity.

  2. Speaking as someone who actually has confirmed chronic deficiencies (potassium, mostly, but some Mg — which exacerbates the K) this is beyond annoying.

    The really obvious symptoms aren’t fatigue, they’re “cramps.” In particular, lower leg cramps. They’re worst after exercise and at high altitude but they’re not the usual “Charley Horse” type cramps, just a dull ache that never quits.

    The good news is that they really are easy to treat, at least in the mild form I have (mild kidney damage from too many years of NSAIDs for arthritis): eat a healthier diet. Reduce sodium, maybe a bit of KCl in the “Lite Salt” formulation (way cheaper than gluconate.)

    Problem solved. The only time the question comes up any more is when I get bloodwork done for something like my knee replacement (ain’t it pretty?) and I have to bump it up a bit the night before.

  3. Jamie

     /  October 18, 2012

    Hi PalMD, love the blog but just thought I’d point out the dig at magnesium powder is unfounded. Clearly you never played with it in chemistry class at school but it’s certainly not spontaneously explosive. Magnesium certainly will give a nice flame if ignited but that’s as far as it goes, chemists would certainly have been resting easy that night. For example, this kid apparently puts the powder through a blender regularly… dropping it through fingers wouldn’t interest even the most ardent health and safety enthusiast

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