Health Benefits of Magnesium

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I can’t stress enough how crucial magnesium is for your health. This amazing mineral is a vital player everywhere in your body and is extremely beneficial for heart health.

Magnesium is involved in more than 300 biochemical functions in your body, supporting:

  • Your heart rhythm
  • Arterial and muscle function
  • Blood pressure
  • Cellular energy

Magnesium improves the metabolic efficiency of heart cells and therefore is a useful treatment for a whole host of cardiovascular conditions. When taken regularly, this mineral can help maintain vascular tone, and therefore helps promote healthy blood pressure, and may also help reverse arterial plaque. Magnesium also acts as a muscle relaxer inside the arteries, helping to alleviate chest pain and other symptoms of angina that are caused by lack of oxygen to, or energy in, the heart.

A shortage of magnesium can cause or worsen congestive heart failure, atherosclerosis, chest pain, high blood pressure, cardiac arrhythmias, heart muscle disease (cardiomyopathy), heart attack, and even sudden death. But what is alarming to me as a cardiologist is how many people are deficient in this key mineral and how this is impacting their heart health.

Magnesium Deficiency is Rampant

Once thought of as a rare condition, magnesium deficiency is an extremely prevalent problem. It’s estimated that over 70% of adults in the United States consume less than the recommended daily allowance (RDA) of magnesium, and 19% consume less than 50% of the RDA1.

What’s going on to cause such a rampant deficiency of this crucial mineral? There are several factors at play, including:

  • Stress: If the stress level in your life is high, especially if you don’t exercise enough, your bloodstream may be flooded with the “fight or flight” hormones adrenaline and cortisol on a regular basis. This causes magnesium to be released from your cells and lost in the urine.
  • Medications: If you are on diuretics or heart medications, you may be depleting your magnesium levels because these drugs are known to cause excretion of magnesium through the kidneys. 
  • Diet: The typical American diet lacks this nutrient. Current farming technology employs large amounts of inorganic fertilizers that are often low in magnesium. Combine that with the overuse of phosphates, nitrates, and ammonia, which drain much-needed magnesium from the soil, and you can see why these environmental factors are adversely effecting magnesium levels.
  • Carbonated Beverages: If you drink a lot of dark colored carbonated beverages you may be flushing magnesium out of your system. That’s because sodas contain phosphoric acid, which is a substance that binds with magnesium inside the digestive tract, making it unusable to the body. But phosphoric acid isn’t the only bad guy when it comes to wreaking havoc on magnesium levels. Another ingredient known to deplete optimal levels is sugar. 
  • High Levels of Calcium Supplements: Calcium and magnesium work synergistically in the body—but without the right balance of these two minerals, magnesium levels get depleted.

How Do You Know if You Have Enough Magnesium?

The fact is, many people are magnesium deficient either due to medical conditions or poor diet and/or other lifestyle habits. But how do you know if your magnesium levels are low?

This can be difficult to answer. You can ask your healthcare professional to test for a magnesium deficiency but be prepared that the results may be misleading. Most hospitals and laboratories measure magnesium levels in the blood, but there is a very weak correlation between the magnesium levels in your blood and how much is found in your heart cells. That’s because less than 1% of total magnesium in your body is present in your blood serum2.

However, if your serum magnesium is low, then it’s highly likely that the level in your heart is low as well. Likewise, if your serum magnesium level is high, there is a reasonable chance that the level in your heart is probably adequate.

A more insidious problem occurs when the serum level falls within the normal range. You (and your doctor) might think all is well, but a normal serum magnesium does not necessarily indicate that the heart has a normal level of this vital mineral.

Modern technology has yet to develop an ideal system for measuring magnesium. Although some tests include measuring levels in blood cells and skeletal muscle, these tests are technically difficult and very expensive.

Because of these pitfalls, I didn’t routinely order serum magnesium tests on my patients. I believe that since magnesium is safe, inexpensive, and easy to use, it should be considered a mineral that deserves more use for chronic and acute cardiological problems.

5 Warning Signs of Magnesium Deficiency

If you suspect a deficiency be on the lookout for these warning signs of low magnesium:

1. Muscle Cramps: To stay healthy, the cells inside your muscles require the right balance of magnesium, potassium, and calcium. When magnesium levels are low, too much calcium gets inside the cells, which in turn over stimulates the cells and makes them jumpy. So, if you find yourself getting leg cramps, charley horses, or muscle twitches frequently, this could be due to a magnesium deficiency.

2. Heart Palpitations: A feeling of a fluttering, racing, and skipping heart beat are one of the scarier signs you may be low on magnesium.

3. High Blood Pressure: Magnesium’s main job is to relax the smooth muscle cells in artery walls, which in turn helps the arteries dilate and stay flexible. But when the reverse happens, and arteries become tense and rigid, blood pressure goes up. Gradually rising blood pressure can be a sign of many things, low magnesium levels among them.

4. Fatigue and Weakness: Magnesium plays an important role in cellular energy. If you’re feeling fatigued, it may very well be an indicator that your magnesium levels are low. If you have a magnesium deficiency, your muscle strength will be compromised too.

5. Depression, Anxiety and/or Insomnia: If you are prone to depression, anxiety, and/or insomnia, it could be due, in part, to low magnesium levels.

Best Food Sources of Magnesium

If you are concerned about your magnesium levels, I suggest adding the following magnesium-rich foods to your diet:

  • Nuts & Seeds: Eaten whole, nuts and seeds are excellent sources of magnesium. Plus, nut butters are also good choices for their magnesium content.
  • Fermented Soy Products: Soy-based foods such as tofu and soy milk tend to be high in the mineral – you’ll get 280 mg of magnesium from 10 grams of raw soybeans.
  • Whole Grains: Quinoa, millet, and short-grain brown rice are good choices.
  • Fish & Seafood: Mackerel, halibut, and salmon are all good sources – just make sure you select wild-caught varieties because of concerns about mercury. Stick with smaller fish like mackerel because they generally have less mercury than larger fish.
  • Beans: Whatever your personal preference—black, lima, kidney, or navy—beans are a great choice to meet your daily magnesium requirement. Chickpeas, lentils, and split peas are also rich in magnesium.
  • Leafy Green Vegetables: Spinach, kale, collard greens, and swiss chard are well-known choices, but don’t forget about kelp and other seaweeds.
  • Avocados: One cup of sliced avocado contains 44 mg of magnesium.
  • Bananas: Bananas are well recognized as a great source of potassium. A medium-sized banana packs 32 mg of magnesium.

Other good sources of magnesium include figs, apricots, and dark chocolate.

Plus, 6 Foods to Avoid

If you want to keep your magnesium levels up, here are some of the things you’ll want to make sure to avoid:

1. Gluten
2. Refined sugar
3. Soda
4. Alcohol
5. Non-organic farmed foods
6. Table salt

Cooking also strips minerals, so opt for plenty of raw nuts, seeds, and veggies.

How Much Magnesium Can You Take?

In addition to eating foods rich in magnesium, I recommend taking at least 400 to 800 mg of magnesium daily. When selecting a magnesium supplement, I recommend taking one that includes all four of the absorbable forms, including: orotate, citrate, taurinate, and glycinate.

A word of caution here: If you have renal insufficiency or kidney failure, do not take a magnesium supplement unless prescribed and monitored by your physician, because excessive levels be dangerous. But if you don’t have renal disease, magnesium supplements may be taken without worry of any significant adverse reactions.

When to Take Magnesium

It’s a good idea to take a magnesium supplement as part of your nightly routine along with brushing your teeth. Sometimes insomnia or anxiety can be caused by muscle tension, which may make you feel as though every muscle in your body is tense. This can cause muscle cramps at night that can disrupt sleep, which is why I recommend taking magnesium at night for the greatest effect.

Magnesium Side Effects

You don’t have to worry about any side effects from consuming too much magnesium from food because the kidneys eliminate excess amounts in the urine.

If you’re concerned about side effects from taking too high a dosage of a magnesium supplement, there’s one tell-tale sign: the need for extra toilet paper! Bowel cleansing and constipation relief are the biggest side effects—if you can call them negatives—of taking too much magnesium! But it’s almost impossible to unknowingly develop toxicity from too much magnesium, because you’ll get loose stools first, and the good news is you can adjust your dosage of magnesium accordingly.

Should You Take Magnesium?

I whole heartedly believe taking supplemental magnesium is a sound health insurance policy. That’s why I recommend a healthy diet of magnesium-rich foods and supplementing with 400 to 800 mg of a broad-spectrum magnesium daily.


More Heart Healthy Advice From Dr. Sinatra


Dr. Stephen Sinatra

Meet Dr. Stephen Sinatra

A true pioneer, Dr. Sinatra spent more than 40 years in clinical practice, including serving as an attending physician and chief of cardiology at Manchester Memorial Hospital, then going on to formulate his advanced line of heart health supplements. His integrative approach to heart health has changed the lives of hundreds of thousands.

More About Dr. Stephen Sinatra