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What you will discover:

  • -Connection between magnesium and athletic performance
  • -Factors that put you at risk for magnesium deficiency
  • -Signs and symptoms of magnesium deficiency
  • -Foods that help and foods that could be hurting your magnesium stores
  • -Lifestyle practices to boost magnesium

Isn’t it great when our bodies function like we want them to?  

Like when our muscles are able to take us from a hanging position on the bar to a supported position above the bar.  Or when our bones support the weight of a max effort back squat.  Let’s not forget the need to pump oxygen throughout our bodies when that high-intensity AMRAP has us gasping for air.  Life is good when the body functions well.  We owe magnesium plenty of thanks for that.

Magnesium (Mg) is the second most abundant element in our bodies and has a role in over 300 metabolic reactions.  Magnesium is considered a macro-mineral since the body needs it in such high quantities.  And it’s one busy element.  From a performance perspective, magnesium is vital in producing the energy needed to hit our workouts hard.  Magnesium also plays a role in protein synthesis.  So magnesium is needed to increase lean tissue and in turn, burn fat.  That just touches the surface of how magnesium supports athletic performance.


Factors that put you at risk for magnesium deficiency

Unfortunately, most of us do not include enough magnesium rich foods in our diet.  As many as 60 percent of us don’t even meet the Recommended Dietary Allowance (RDA) for magnesium.  If you’re an adult female, you need at least 320 mg of Mg per day.  Adult males need even more at 420 mg per day minimum.  As athletes, our daily magnesium needs increase to meet the heavy energy demands we place on our bodies to move more weight further and faster every day.  At close to max effort, our magnesium needs could increase as much as 20 percent.  As athletes in the box, we push to our max almost daily.  After all, we love the grind.

In addition to high demands from exercise and inadequate intake from diet, consider two other dietary factors that can put you at risk for a magnesium deficiency.  A diet high in saturated fat can decrease magnesium absorption by the body.  Don’t worry.  Butter and coconut oils are still part of a healthy diet.  I would suggest eating bacon and sunflower seeds at different meals though.  And actually chewing the sunflower seeds so your body is better able to extract the magnesium during digestion.  Another dietary caution when it comes to magnesium absorption is excessive sugar intake.  High sugar intake actually signals the kidney to excrete more magnesium in your urine.

What a waste...pun intended!

Aside from diet and exercise, let’s take a look at some other lifestyle factors that put us at risk for a magnesium deficiency:

  • Taking medications like estrogen (birth control pills) or inhaled corticosteroids (asthma inhalers)

  • Recent surgery

  • Hormone imbalances

  • History of diabetes or hypertension

  • Chronic stress or chronic sleep deprivation


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Signs and symptoms of magnesium deficiency

Signs and symptoms are tricky.  Take fatigue for example.  What is fatigue NOT a symptom of?  That said, there are some symptoms associated with magnesium deficiency that you should be aware of.  If unexplained by other means and/or you have some of the risk factors listed below, magnesium could be the hidden cause of your distress.  Of note, blood work is not a good indicator of magnesium deficiency.  Only 1% of the magnesium we store in our bodies stays in the blood.  So, unless you are severely depleted, blood work is not going to indicate you may have a problem...or prove that you are okay.

The following list includes some of the physical symptoms of magnesium deficiency including common mind and body problems.  

  • Irritability (extremely grumpy)

  • Anxiety (extreme worry)

  • Lethargy (extremely tired)

  • Memory loss

  • Weakness

  • Muscle spasms

  • Muscle cramps

  • Impaired coordination


In addition to the symptoms above, having the following chronic medical conditions could be a sign of chronically low magnesium.

  • Depression

  • Chronic fatigue syndrome

  • Sleep problems

  • Migraine headaches

  • Premenstrual syndrome

  • Hypertension

  • Diabetes

  • Asthma


I find the magnesium and blood sugar connection particularly interesting.  The cycle works as follows:  

  1. Low magnesium causes high insulin.  
  2. High insulin causes our body to get rid of even more magnesium through urination.1
  3. Thus, low magnesium results in even lower magnesium.  
  4. With chronically low magnesium causing chronically high insulin, the body eventually fatigues and becomes less sensitive to insulin which opens the door for hyperglycemia and diabetes. Fascinating!

With such a strong connection to overall health and performance, I want to make sure you have all the tools you need to tip the scale in your favor and ensure you have enough magnesium on board to cover the high demands you place on your bodies.  I wouldn’t be a good nutrition coach if I didn’t.  Use the steps below as a starting point.



Step 1: Prioritize Magnesium Rich Foods in Your Diet


Fortunately, there are plenty of foods considered good sources of magnesium.  Even better, many of you are probably already eating these foods to some degree.  Particularly those of you following a paleo, clean eating, or vegan diet.  

Whoot!  Whoot!

Here’s a table showing you foods that provide at least 25 percent of the RDA for magnesium.  Try to include them in your diet daily with consideration for your preferences and nutrition plan.  If you have allergies, sensitivities, or intolerances to one or more of these foods, you may want to talk to a dietitian about some alternatives.  Each food includes a list of added benefits for fun.  After all, when you eat nutrient dense, real foods, you benefit from more than just the magnesium.






Pumpkin seeds

¼ cup

191 mg

High in zinc


1 cup

157 mg

Gut protective

Swiss Chard

1 cup

151 mg

Blood sugar stability


1 cup

148 mg

Protein rich plant food

Black beans

1 cups

120 mg

Colon health


0.75 cup

118 mg



0.25 cups

117 mg

Heart health

Sunflower seeds

0.25 cups

114 mg

High in vitamin E


I love that this list contains leafy greens, healthy, chewable fats, and quality starches.  Add some seafood or lean meat/poultry and you have a meal.  Check out our salmon and spinach bake here for some inspiration. Bonus for the vegans who can get a complete meal from the above table without additions.  


Step 2: Save Saturated Fat for Another Meal

In addition to aging, stress, and illness, certain food combinations can make absorption of magnesium difficult.  I mentioned this earlier, but diets high in saturated fat and added sugar can decrease your body's ability to absorb magnesium.  Full-fat dairy products like butter and cheese, fatty meats like a rib eye or T-bone, and lard contain large amounts of saturated fat and should be consumed away from magnesium rich foods.  Sugar laden foods like juice, syrups, and most desserts should take back stage when trying to boost magnesium intake.  Especially since these foods actually encourage your body to dump magnesium.  Concentrated sweets don’t really promote health anyway and should not be a staple of any healthy nutrition plan. Check out some surprising benefits of giving up added sugar here


Step 3:  Discuss Supplements with your Dietitian or Nutrition Coach

You may be wondering about supplementation.  If you’re not getting enough from food, and you have higher needs from workouts, wouldn’t a supplement make sense? A review of the research regarding magnesium supplementation and athletic performance came to the conclusion that there isn’t enough evidence to support the use of magnesium supplementation as an athletic enhancement aid.2 Sure there was some benefit, but the studies were small and typically involved small groups of young healthy males.  

That said, if you do decide to supplement orally, let me give you some helpful nutrition coaching.  First, look for supplements that absorb easily like magnesium glycinate and magnesium citrate.  Don’t waste your money on magnesium oxide or magnesium carbonate supplements that your body has a hard time absorbing.  Second, start small with your dosing and work up to tolerance.  Taking too much at once could have you running to the bathroom if you know what I mean.  In fact, one of the best ways to determine your optimal dose of supplemental magnesium is the presence of comfortably loose stools.  I suggest starting with 240 to 315 mg of magnesium and working up from there.


Step 4: Let it in Through your Skin

Do you want to know the coolest thing about magnesium?  You don’t have to consume it to get the benefits.  Your skin can do that for you!  No, it’s not like vitamin D where your skin makes the vitamin from the sun.  But, if applied to the skin, your body will absorb it, even more efficiently than from eating magnesium rich foods.  That’s so cool.  Here are some tips for boosting your magnesium intake sans nutrition.

  1. Soak in the tub.  Taking an Epsom salt bath is a not so quick, but oh so relaxing way to boost your magnesium intake.  Try this recipe out next time you’re in the mood to decompress and soak those achy muscles: 1 cup Epsom salt, 1/2 cup baking soda, 10 drops lavender essential oil (or whatever oil floats your boat). Soak for 30 minutes.

  2. Play in the ocean.  OK, so this one is not possible for everyone I know.  But, have you ever been on a vacation where you did get to play at the beach all day for a week or so.  Tell me you didn’t feel great.  Sea water is chock full of minerals including magnesium.  If you’re deficient, the water may even make your skin tingle.

  3. Rub some magnesium oil directly on your skin.  For those of you that don’t have time for a bath (I hear ya!), you can rub magnesium oil directly on your skin.  You can purchase it online or make your own.  There are several recipes available, but since I’m a fan of Wellness Mama, I’m going to give you hers.  Put ½ cup of magnesium chloride flakes in a bowl and pour ½ cup of boiling distilled water over the flakes.  Stir until completely dissolved and allow to cool before transferring to a container (preferably a glass spray bottle).

Which one will you be trying first?


A Dietitian’s Take:

With involvement in over 300 metabolic reactions, some of which have a direct impact on performance, ensuring you eat enough magnesium rich foods should be high on your list of nutrition priorities.  That said, meeting your recommended magnesium intake goals should not be a chore.  If you’re doing what we teach at Nutrition WOD and consuming a variety of nutrient dense, real foods, you’re covered.  If you have risk factors and are experiencing some of the symptoms associated with magnesium deficiency, take the steps listed above to ensure your magnesium gets back on track.  Whether you make magnesium rich foods a priority in your diet, avoid eating too much-saturated fat and sugar with those foods, or decide to let your skin do some of the work for you, your body will thank you.

  1. Higashirua K, Shimamoto K. Magnesium and Insulin Resistance. Clin Calcium. 2005;15(2):251-4.   

  2. Volpe S. Magnesium and the Athlete. Current Sports Medicine Reports. 2015;14(4):279-283.  

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