What you’re in for: A delightful little number on the second most abundant electrolyte in your body and why I think you should keep yourself topped up with it. 5 minutes reading. I also apologise for the meme. It’s really hard to find an interesting picture of magnesium.
Ok so that might just be the most blown out of proportion title I could come up with for this post, but Magnesium is pretty damned important for our general health.
You might remember magnesium being that little strip of metal you had endless fun with in science class putting into the flame of a 1960s bunsen burner. This is not, however, the same as dietary magnesium and I implore you not to get your kids to steal a handful from their science teachers cupboard to sprinkle on you cornflakes. It will not end well!
The magnesium I am talking about is found in high quantities in leafy greens as well as nuts, not in petri dishes.
Your typical western diet will ensure that you are deficient in this mineral, so much so that it is the most common deficiency behind only Vitamin D (1). This is largely down to our over-consumption of grain based carbohydrates, which are low in magnesium, and our under-consumption of leafy green vegetables, which are high in magnesium and other vital nutrients. The typical food pyramid we have all seen since the days of primary school is wrong and has lead to a sick society with more deficiencies than I care to mention.
Magnesium is the second most abundant electrolyte found in the human body and is responsible for many, many different functions. It is critical to preserving brain function in periods of down-time as well as helping to regulate muscle contraction.
Depletion of this mineral has been associated with increased blood pressure, reduced glucose tolerance and poor sleep quality. Athletes are especially at risk as magnesium is lost through sweat during periods of intense exercise. If your magnesium levels are low you may experience cramps and muscle pain during exercise.
Will it turn you into Novak Djokovic? Probably not. However, there is a study which suggests that supplementing with magnesium may improve performance by improving blood oxygen levels. This study was performed in triathletes and was indicative of improved times in 500m swimming, 20km biking and 5km running, although only the swimming was statistically significant (2). More studies need to be done in this fashion to get more solid results.
How does this apply to me?
Magnesium is one of the few supplements I recommend for active people take as it is so easily depleted and often not properly topped up. As well as its important neurological and physiological functions it has also been shown to reduce stress levels, which I think can be beneficial for a lot of people.
There has been a study where one group of persons with recently diagnosed mild hyper-tension supplemented with 600mg of magnesium over the course of 12 weeks. There blood pressure was shown to have decreased in small but significant amounts when compared to a group supplementing with a placebo (3).
Supplementing with between 200mg and 400mg (the former for women, the latter for men) every evening before bed will help to improve sleep quality if you are deficient in the mineral. Any more may cause gastrointestinal stress and have a laxative effect, which nobody wants.
When looking at which types of magnesium to buy, there are several options. Magnesium glycinate is probably the best option to shoot for as it has a much higher bioavailability (can be absorbed better) than magnesium carbonate (2.3x more bioavailable), magnesium citrate (3.6x) and magnesium oxides (8.8x). When it comes to supplements like these you shouldn’t be afraid to shell out a bit more for the product. ‘If you pay less, you pay twice’ as they say. Magnesium oxide is what is generally used in your typical ‘health’ stores such as Holland & Barrett whereas higher quality, pharmaceutical grade glycinate can be found in higher end supplement lines.
Bottom line is I think that as an active individual you should supplement with magnesium. At best it reduces blood pressure, stress levels, improves sleep quality and performance. At worst it gives you the trots. What have you got to lose?
1. What we eat in America: NHANES 2005-2006
2. Golf SW, Bender S, Grüttner J On the significance of magnesium in extreme physical stress . Cardiovasc Drugs Ther. (1998)
3. Hatzistavri LS, et al Oral magnesium supplementation reduces ambulatory blood pressure in patients with mild hypertension . Am J Hypertens. (2009)