Magnesium is one of the most important essential minerals for human health, along with sodium, potassium, and calcium. It’s known to be a vital cofactor for several hundred metabolic processes that keep us alive and well (some estimates suggest magnesium is need for up to 600 different biochemical reactions in our bodies!).
Magnesium is so important, but surprisingly it’s one of the most common mineral deficiencies amongst our population and is reason why it’s part of our core supplement recommendations.
Our bodies contain about 25 milligrams of magnesium, most of which is found in our bones, muscles and brain. About 1% of our magnesium circulates through our bloodstream.
Magnesium is involved in protein synthesis, nerve conduction, energy metabolism, DNA and RNA synthesis, antioxidant production, muscle contraction and maintaining normal heart rhythms, to name a few.
It’s so vital for our bodies to function as designed that even marginal insufficiencies are known to impair health and performance [i].
Why our magnesium status usually isn’t optimized (and how to tell if yours are).
The Recommended Dietary Allowance (RDA) for most people to avoid deficiency syndromes are set at 320mg for women and 420mg for men, but dietary surveys suggest many adults fail to meet these levels through diet alone [i].
Western diets are likely adequate enough in magnesium to avoid frank (clinical) deficiencies, but intakes are not high enough to establish the high normal serum magnesium concentrations that are protective against various [chronic] diseases [iii].
Over the past several decades our food supply has become less nutrient dense and more refined as we’ve drifted towards the convenience foods that pack the shelves of our grocery stores. Even if you try to eat a wholesome, unprocessed diet like the 2000 calorie example below, you’d be consuming just under 400mg of magnesium each day, which is just shy of the RDA for sedentary men:
Additionally, several patterns in our modern lifestyles increase our need for magnesium either by increasing magnesium losses or elevating the amount of dietary magnesium required.
Some of the dozens of factors beyond magnesium consumption that increase risk of insufficient magnesium absorption or status are [iv]:
- Caffeine use
- Diuretics (common blood pressure medications)
- Insulin resistance or Type 2 diabetes
- Antibiotic use
- Alcohol consumption
- Gastrointestinal disorders and diarrhea
- Proton pump inhibitor or antacid use
- Calcium supplement use or intake of calcium-fortified foods/beverages [v][vi][vii]
- Phosphoric acid intake (such as dark colas, diet or regular)
- Vitamin D deficiency/insufficiency
- Vitamin B6 deficiency/insufficiency
- Strenuous exercise
- Emotional or psychological stress
- Excessive ingestion of poorly absorbable magnesium (such as the oxide, chloride or citrate forms used in most bargain brand mineral supplements)
Diagnosing magnesium deficiency is extremely difficult as there isn’t just one method of measuring magnesium status; there are tests to measure blood serum levels, red blood cell saturation, tissue concentrations, urine, and saliva, but none of them are individually reliable enough to stand out as a “gold standard” method.
Even without clinical measurements of low magnesium status, you may be able to recognize signs of low or insufficient magnesium status in yourself from this partial list:
In my experience, whenever I meet someone who doesn’t feel as awesome as they want to feel and haven’t quite optimized their dietary nutrient intake, it’s safe to assume their magnesium status is marginal at best.
How can you get more magnesium?
The ideal way to optimize magnesium intake and minimize the negative risk factors caused by inadequate magnesium status is to eat more of the foods that are naturally high in magnesium:
- Nuts & seeds
- Leafy greens, especially spinach
- Beans & legumes
- Salmon or Halibut
- Dark chocolate
- Whole grains
Looks a lot like the example diet shown above, doesn’t it? This illustrates just how difficult it is to get optimal intakes of magnesium. This type of dietary shift works best if done while also reducing/minimizing caffeine and alcohol and limiting sugary foods and beverages.
It’s also worth noting again that our magnesium needs elevate when we consume excess calcium from food and/or supplements, and many commonly consumed foods and beverages such as prepared cereals, breads, orange juice, and non-dairy ‘milks’ are fortified with calcium but are poor magnesium sources.
Calcium is an excitatory ion in our bodies, which means it’s good at helping with muscle contraction or tension, while magnesium is needed to help counterbalance these effects to allow our muscles to relax. Perhaps this is why we’re beginning to recognize that our aggressive recommendations for calcium fortification and supplement use is directly increasing risk of cardiovascular events? [viii] [ix]] [x]
What about supplements?
Whenever dietary intake of a nutrient is inconsistent, marginal or insufficient, I turn to supplements to fill in the gaps or right-size nutritional intake and status. While all vitamins and minerals are important for optimal health, magnesium is perhaps one of the most widely helpful for a variety of metabolic processes.
If you review the available research for yourself, you’ll find hundreds, if not thousands, of well-designed studies on beneficial effects of magnesium supplementation in people with or without chronic disease.
The surprising thing to me is that many of these issues related to insufficient magnesium status are “sub-clinical”, meaning the problems caused by inadequate magnesium status are not detectable by current disease state definitions, but are significant enough to put a burden on the individuals’ health and also place enormous burden on our healthcare system as a whole.
Many of the most common chronic conditions (depression, anxiety, blood pressure, or glucose balance issues) and causes of death (heart attack or stroke) may be alleviated or reduced if we simply incorporated a better supplement routine as we also try to clean up our diets.
Just take a look at some of the positive impacts magnesium supplementation (in addition to dietary intake) has shown in human clinical studies:
- Magnesium supplementation may have a beneficial effect on subjective anxiety in those prone to anxiety [xi]
- Supplementing with just under 400mg of magnesium daily significantly improved plasma glucose in those with pre-diabetes [xii] and improved insulin sensitivity in non-diabetic subjects with low (but not clinically critical) serum magnesium [xiii][xiv]
- 3 months oral magnesium supplementation decreased hsCRP levels (a marker of inflammation) in apparently healthy subjects with pre-diabetes [xv]
- Improves metabolic profile and blood pressure of “Metabolically-Obese, Normal Weight” individuals [xvi]
The dosing for most of the available studies are between 200mg and 600mg per day of magnesium, and the positive effects on various health conditions appear to start near the middle of that range. In other words, regardless of dietary intake, the supplement doses that appear impactful are in line with the current RDAs.
Even at these seemingly high intake levels, risk of anything negative happening are minimal with magnesium. The most common unwanted effects of getting too much magnesium are loose bowel movements, as too much magnesium (especially certain forms) can create a laxative effect.
If you and your doctor decide that adding a magnesium supplement is in your best interest, don’t just go out and buy the cheapest magnesium you can find. Magnesium comes in different forms, many of which are poorly absorbed or not well tolerated.
Magnesium Oxide or Carbonate are perhaps the cheapest, most widely available forms found in supplements. Absorption or ‘bio-availability’ from these forms is very low. These are the forms usual found (in inadequate amounts) in bargain brand once-daily vitamin and mineral supplements. If you take a few hundred milligrams of these forms, you’ll want to be close to a bathroom.
Magnesium Citrate is another cheap, common salt form with decent absorbability at low doses (under 200mg at a time). However, if you need higher amounts, you’ll want to avoid the citrate form if possible since higher doses are commonly used as laxatives or colonoscopy preps.
Magnesium Glycinate is a favorite form of functional medicine practitioners because it’s very well tolerated and very well absorbed, even at high doses. It’s comprised of elemental magnesium bound to glycine (actually two glycines as a bisglycinate). It is quite a bit more costly, and typically exerts a sedative effect compared to other forms. Life Time currently uses Magnesium Bisglycinate in our AM/PM Multivitamin formulas.
Magnesium Threonate is a newer form that’s been shown to be best at crossing the blood-brain barrier to exert its effects on cognition, memory, and sleep. For the high price tag, it’s a relatively inefficient source for promoting whole-body magnesium status since only a few milligrams of magnesium can be delivered per 100mg of material (so it takes up a lot of physical space in supplement formulas).
Di-magnesium Malate, a magnesium salt combining two molecules of magnesium with malic acid, may be the best combination of bio-availability (absorbability), price, and metabolic support. It’s easy on the GI tract, delivers a high concentration of elemental magnesium, and is affordable. The malate form is also thought to help support everything from blood pressure and stress resilience, to sleep quality and pain control. The malic acid portion is also extremely helpful for all our cells to use in energy (ATP) production without exerting stimulant effects. It’s being investigated as a potential management method for chronic fatigue and fibromyalgia pain [xvii].
Check your supplement cabinet at home and chances are you’ll find oxides, carbonates, or citrates in the products you take. Also check the dose, as most multivitamin/multi-mineral formulas sold in mass retail stores only include 50-100mg of these cheap, poorly absorbed magnesium forms, which should make you question whether or not you’re taking something that can actually benefit your health.
If you’re trying to optimize your health and magnesium status, start by taking a high-quality multivitamin (Life Time’s all contain at least 150mg of magnesium per day in the Bisglycinate form), and consider taking additional magnesium to complement your wholesome diet. Just choose the form wisely.
Life Time is preparing to introduce a standalone Magnesium Malate product as well as a combination Calcium + Magnesium Malate product for those looking to support mineral intake and overall health. Talk to a fitness professional today to get more familiar with which supplements may help support your health and fitness program, and as always consult with your doctor before making any significant changes to your supplement routine.
In health, Paul Kriegler – Corporate Registered Dietitian
This article is not intended for the treatment or prevention of disease, nor as a substitute for medical treatment, nor as an alternative to medical advice. Use of recommendations in this and other articles is at the choice and risk of the reader.