Hoping this can be a TTMJ post.

A question has been plaguing me, as I am sure is others, in regards to magnesium deficiency. Reports are indicating 1 in 5 Americans are not getting enough of their recommended daily allowance. Is this from poor micronutrient content in our food or just not selecting the proper foods? What is concerning is that number includes children as well as adults.

Recently, on PA Radio, Dr. Wiley commented he has seen a large magnesium deficiency in his practice, so the question begs, how do we supplement and how much?

As athletes, do we require more than the RDA to make sure our body is recovery and moving towards performance increases?

What are your views and recommendations on magnesium?

Thanks for your time!




Thanks for contacting me with an interesting topic. A few concerning things came up when researching magnesium deficiency.

According to most doctors, mineral deficiency isn’t much of factor for a healthy individual eating a healthy, non restrictive diet. But then why do recent studies state that up to 75% of Americans are deficient in magnesium?

There are host of diseases and illnesses related to mineral deficiencies. This seems to be a simple fix, but then why don’t more health care providers test for micronutrient deficiency?

Lets start by looking at some of the factors that might result in a mineral deficiency like magnesium.

Mineral deficiencies come in three ways, either you are not eating enough of something, not absorbing it or some lifestyle factors leading to the deficiency.

Lets examine what foods are high in magnesium and what factors might lead to a mineral deficiency.

The USDA recommends a daily intake 320/420 mgs of magnesium a day for a healthy women/man, but I believe that number is low for hard charging athletes; up to 20% can be lost during exercise. (1)


The following foods are listed as high in magnesium.

Dark Leafy Greens – 1 cup of cooked spinach, kale, swiss chard and collard greens will give you ~157 mg of magnesium.

Nuts and Seeds – Sesame seeds, Brazil nuts, almonds and cashews are all high magnesium. ½ cup will give you 325 mg of magnesium.

Fish – Fish like mackerel, wild salmon, halibut, and tuna are good sources of magnesium. With each serving offering about 100 mg of magnesium.

Avocados – each avocado offers about 58 mg of magnesium.

Tap Water – yes, the “earthy” water that flows out of the tap (or H20 coming out of the hose) that has not been treated by soft water filters is high in mineral content. Tap water offers important minerals like calcium, magnesium and sodium that are not found in bottled water.

I remember growing up as a kid and drinking from the hose and the faucet. I do remember the first time I saw someone drinking water from an Evian bottle and I thought it would never catch on; how wrong was I. However, recent studies examining tap water, mineral content and commercially produced bottle water tell an interesting story. The mineral content of the American produced bottled water contains very low mineral levels and could be contributed to the magnesium deficiency.

“Because of their lower intake requirements, children may fulfill an important portion of their DRIs by drinking tap water. Toddlers in certain North American regions may fulfill 17% of their Ca2+ DRI and 50% of their Mg2+ DRI by drinking 4 glasses (1 L) of tap water per day.” (2)

Saying if your diet didn’t include leafy greens, fish, nuts, avocados and a few glasses of tap water, you could be deficient in trace minerals is just too easy. But what if you are eating these foods and drinking a gallon of water straight from the hose?

The big player here is the body’s absorption of trace minerals. This is something myself and Tom Incledon have discussed for years. How could someone consume something and not get the benefit for it?

Easy – inflammation in the gut can reduce the body’s ability to absorb minerals. This can happen over a large spectrum from base level gut inflammation all the way to complex autoimmune diseases like Leaky Gut.

And what is Leaky Gut you ask? My first client when I retired from the NFL was diagnosed with Leaky Gut so I educated myself real quick on the effects and how debilitating it can be.

The mucosal lining in the gut is the largest part of the body’s immune system. The small intestine is permeable so the proper nutrients get through; I liken it to an organ made of cheesecloth. Spots in the gut wall open and close to admit the good stuff as the contents of the intestines pass by. Only certain nutrients are absorbed if they are sufficiently broken-down and in the right form. Everything else is sent down the line to be excreted by the body. However, when the pores become too big or the screening process breaks down, the intestines become “hyperpermeable”. The name most used for this is, Leaky Gut Syndrome – this happens when the intestines become damaged and the wall becomes porous to the extent that some of the contents passing through the intestines are allowed to get into the bloodstream.

Now are people with leaky gut the only ones that can’t absorb nutrients? No, those who have basic gut inflammation can struggle with nutrient absorption, myself included. I dealt with low mineral levels for years; every time I got my blood work done I was low in zinc, magnesium and iron. It wasn’t until I started supplementing with minerals, eating foods like those listed above, and addressing my gut inflammation by removing foods I was allergic to did things improve. I noticed the effects almost immediately, as the body needs zinc to produce testosterone.(3)

Inflammatory foods are usually unique to the individual and can be found through a food allergy panel. However, there has been a long-standing battle against phytic acid by the Paleo community. Experts relate phytic acid as an anti-nutrient and the cause of malabsorption of trace minerals including magnesium. Phytic acid is most commonly found in grains, legumes, nuts, soybeans and seeds. Phytates perform an essential role in plants, as they are an energy source for the sprouting seed. When a seed sprouts, phytase enzymes break down the stored phytates.

Phytic acid has been shown to bind to minerals in the gut before they are absorbed and influence digestive enzymes. Phytates also reduce the digestibility of starches, proteins, and fats.

“Magnesium absorption was ≈60% lower when phytic acid was added to phytic acid-free white-wheat bread at an amount similar to that in whole-meal wheat bread (1.49 mmol/200 g) and ≈25% lower when added at an amount similar to that in brown bread (0.75 mmol/200 g). The inhibiting effect of phytic acid was dose dependent (P < 0.005). Although this is the first time that the inhibition of magnesium absorption by phytic acid was observed with single meals, such an effect was indicated by chemical balance studies in humans that evaluated phytic acid added to white bread and dephytinized bran.” (4)

It is good to note there are processes available to reduce phytic acid in these foods – fermentation, processing, soaking and heat have all been found to reduce phytic acid grains, legumes and seeds.

While the consuming of phytic acid might be a player in the poor magnesium absorption, I don’t believe it is as impactful as the regular consumption of say….carbonated beverages.

Most dark colored sodas contain phosphates and these bind with magnesium in the digestive tract rendering it unavailable to the body. This effect flushes magnesium from the body.

What about eating donuts, desserts and sweets? Refined sugar contains no magnesium and causes the body to excrete magnesium through the kidneys.

And drinking coffee, tea and other caffeinated drinks? Kidneys control magnesium levels and the primary function of the kidneys is to filter and excrete. Caffeine causes the kidneys to work harder thus lowering the levels of minerals in the body.

How about a few drinks of booze a night? Alcohol, like caffeine, is a diuretic. A diuretic increases the excretion of fluid through the kidneys and can reduce magnesium levels.


How many days week do you perform “hard exercise”?

Just to clarify, I classify “hard exercise” as anything resulting in a high heart rate and excessive sweating. Things like testing heavy back squat singles, CrossFit, circuit training or sprinting are hard exercise. Doing a fun Zumba class or Bar method is not. It is more of an illusion for those that prefer the wool pulled over their eyes to actual hard work; but I will save that for another time.

Magnesium is involved in processes that affect muscle function including oxygen uptake, energy production and electrolyte balance. When you exercise you lose fluid. The fluid is replaced rapidly by the consuming of water or other fluids. Many times that water does not contain trace minerals that are lost during sweating and excretion of fluid from kidneys.

“This research has shown that exercise induces a redistribution of magnesium in the body to accommodate metabolic needs. There is evidence that marginal magnesium deficiency impairs exercise performance and amplifies the negative consequences of strenuous exercise (e.g., oxidative stress). Strenuous exercise apparently increases urinary and sweat losses that may increase magnesium requirements by 10-20%. Based on dietary surveys and recent human experiments, a magnesium intake less than 260 mg/day for male and 220 mg/day for female athletes may result in a magnesium-deficient status.” (5)

Then there is the correlation between magnesium deficiency and low Vitamin D levels. Magnesium helps with vitamin D by activating it in a form the body can use. This aids the body in maintaining calcium, which is essential for bone health.

How does magnesium deficiency effect athletic performance?

Magnesium plays a pivotal role in both anaerobic and aerobic energy production with the metabolism of ATP (adenosine triphosphate). ATP is key from an energy standpoint as every cell in our body stores energy through ATP. This allows for a continuous supply of energy to facilitate everything from protein synthesis to muscle contractions. ATP is like a battery; it stores energy when it is not needed and releases energy when it is. If magnesium is low, then the body does not have the available raw materials it needs to convert calories to ATP. You can see where this could be a negative for athletic performance.


And lastly, what problems or illnesses might a person have that could be related to magnesium deficiency?

Diseases like Crohn’s disease, Type II diabetes, celiac disease, cystic fibrosis, Parkinson’s disease, coronary artery disease, atherosclerosis and short bowel syndrome. And other problems like depression, chronic fatigue syndrome, ADHD, epilepsy, sleep problems, cluster headaches, osteoporosis, premenstrual syndrome, chest pain (angina), hypertension and asthma.

It is pretty clear magnesium deficiency is a problem facing Americans whether coming from not consuming the right foods, not drinking the right water, lifestyle or hard exercise.

Nevertheless, you should be getting regular blood work done that involves micronutrient testing. The only way you are going to know if you are deficient is to be tested for it. You can take the shotgun approach, pull the trigger and see what happens, but I prefer to not work blindfolded.

As I have stated you could be eating all the proper foods, drinking water from the tap and not consuming any soda or sweets and still be low based on low levels of vitamin D.

The only way you will know is to contact a group like Human Performance Specialists, your doctor or health care provider and get mineral testing done.