By Dr. Mercola
Magnesium is vitally important for biological function and optimal health. It's the fourth most abundant mineral in your body, and researchers have detected more than 3,750 magnesium-binding sites on human proteins.1
More than 300 different enzymes also rely on magnesium for proper function. This reflects the impact magnesium has on your biochemical processes, many of which are crucial for proper metabolic function. This includes but not limited to:
- Creation of ATP (adenosine triphospate), the energy currency of your body2,3
- Relaxation of blood vessels
- Muscle and nerve function, including the action of your heart muscle
- Proper formation of bones and teeth
- Regulation of blood sugar and insulin sensitivity, which is important for the prevention of type 2 diabetes4,5,6,7 (In one study,8 prediabetics with the highest magnesium intake reduced their risk for blood sugar and metabolic problems by 71 percent)
Lack of Magnesium Can Trigger Serious Health Problems
If you're lacking in cellular magnesium, it can lead to the deterioration of your cellular metabolic function, which in turn can snowball into more serious health problems.
This includes migraine headaches,9,10 anxiety and depression (magnesium acts as a catalyst for mood-regulating neurotransmitters like serotonin), fibromyalgia,11 cardiovascular disease, sudden cardiac death, and even death from all causes.
Magnesium also plays a role in your body's detoxification processes (including the synthesis of glutathione) and is therefore important for minimizing damage from toxic exposures.
Perhaps most importantly, magnesium is vital for the optimization of your mitochondria, and this has enormous potential to influence your health, especially the prevention of cancer, but also for general energy and athletic performance.
The Importance of Magnesium for Mitochondrial Health
Mitochondria are tiny bacteria-derived organelles residing inside your cells. Your organs need energy to function properly, and that energy, known as adenosine triphospate or ATP, is largely produced in the mitochondria.
Mounting evidence suggests that most health problems can be traced back to mitochondrial dysfunction, so making sure you get the right nutrients and precursors your mitochondria need for optimal performance is extremely important for health, disease prevention, and exercise performance.
As explained by mitochondrial researcher Rhonda Patrick, Ph.D., in the video above, magnesium plays an important role. Without it, other strategies aimed at improving mitochondrial health simply may not work.
Take athletic performance for example. It is in part dependent on your oxidative capacity, meaning the ability of your muscle cells to consume oxygen, and your oxidative capacity relies on your mitochondria's ability to produce ATP by consuming oxygen inside the cell.
You can increase your oxidative capacity in two ways, and both require magnesium:
- Increasing the total number of mitochondria in your cells by engaging in exercise. However, in order for new mitochondria to be created, you must have sufficient amounts of magnesium.
- Increasing the efficiency of your mitochondria to repair damage and produce ATP. This process also requires magnesium as a co-factor.
How Much Magnesium Do You Need?
A century ago, people got an estimated 500 milligrams (mg) of magnesium from their diet, courtesy of the nutrient-rich soil in which the food was grown. Today, estimates suggest we're only getting 150 to 300 mg a day from our food.
Organic unprocessed foods tend to be your best bet, but since the magnesium content of your food depends on the richness of magnesium in the soil in which the plant was grown, even organics are no guarantee you're getting high magnesium content.
Most soils have become severely depleted of nutrients, and for this reason, some magnesium experts believe virtually everyone needs to take supplemental magnesium.
The recommended daily allowance (RDA) is around 310 to 420 mg per day depending on your age and sex,12 although some researchers believe we may need as much as 600 to 900 mg/day for optimal health.
Dr. Carolyn Dean, author of "The Magnesium Miracle," suggests using your intestinal reaction as a marker for your ideal dose. Start out by taking 200 mg of oral magnesium citrate per day, and gradually increase your dose until you develop slightly loose stools.
When your body has too much magnesium it flushes it out the other end, so in this way you can determine your own individual cutoff point. (Be sure to use magnesium citrate, as it's known for having a laxative effect. It's also better to divide your dose and take it two or three times a day instead of one large dose.)
When it comes to magnesium supplements, my personal preference is magnesium threonate. It seems to be most efficient at penetrating cell membranes, including your mitochondria, which can help boost your energy level. It also penetrates your blood-brain barrier and may help improve memory.
If you struggle with headaches or migraines, magnesium threonate may be a good alternative for that reason as well. (For headaches and migraines, make sure you're getting enough vitamin B12 and Coenzyme Q10 as well.)
Risk Factors, Signs and Symptoms of Magnesium Deficiency
A primary risk factor for magnesium deficiency is eating a processed food diet, and the reason for this is because magnesium resides at the center of the chlorophyll molecule. If you rarely eat leafy greens and other magnesium-rich whole foods (below), you're likely not getting enough magnesium from your diet.
Magnesium is also lost through stress, lack of sleep, alcohol consumption, and prescription drug use (especially diuretics, statins, fluoride, and fluoride-containing drugs such as fluoroquinolone antibiotics), and tend to decline in the presence of elevated insulin levels.13 These are all factors that affect a large majority of people in the Western world, so it's not so surprising then that anywhere from 50 to 80 percent of Americans are thought to be deficient in magnesium.
Unfortunately, no lab test will give you a truly accurate reading of your magnesium status. The reason for this is because the vast majority of the magnesium in your body is found in bones and soft tissues. Only 1 percent of it shows up in your blood. That said, some specialty labs do provide an RBC magnesium test that can give you a reasonable estimate. Perhaps the best way to ascertain your status is to carefully evaluate and track your symptoms.
Early signs of magnesium deficiency include "Charlie horses" (the muscle spasm that occurs when you stretch your legs), headaches/migraines, loss of appetite, nausea and vomiting, fatigue or weakness. These are all warning signs indicating you probably need to boost your magnesium intake. More chronic magnesium deficiency can lead to far more serious symptoms such as abnormal heart rhythms and coronary spasms, seizures, numbness and tingling, and personality changes.
Dr. Dean's book, "The Magnesium Miracle," contains a far more exhaustive list of signs and symptoms, which can help you determine whether or not you might be deficient. You can also follow the instructions in her blog post, "Gauging Magnesium Deficiency Symptoms",14 which will give you a check list to go through every few weeks. This will also help you gauge how much magnesium you need to resolve your deficiency symptoms.
What Are the Foods High in Magnesium?
The best way to maintain healthy magnesium levels is to make sure you're eating plenty of dark-green leafy vegetables. Juicing your greens is an excellent way to increase your magnesium, along with many other important plant-based nutrients.
Again, if you eat organic whole foods and show no signs of deficiency, you're probably getting sufficient amounts from your food. If you eat well but still exhibit deficiency signs, you may want to consider taking a supplement as well. When it comes to leafy greens, those highest in magnesium include:
✓ Swiss chard
✓ Turnip greens
✓ Beet greens
✓ Collard greens
✓ Brussel sprouts
✓ Bok Choy
✓ Romaine lettuce
Other foods that are particularly rich in magnesium include the following:15,16,17,18
✓ Raw cacao nibs and/or unsweetened cocoa powder
One ounce (28 grams) or raw cacao nibs contain about 64 milligrams of magnesium, plus many other valuable antioxidants, iron, and prebiotic fiber that help feed healthy bacteria in your gut.
One medium avocado contains about 58 mg of magnesium, plus healthy fats and fiber, and other vitamins. They're also a good source of potassium, which helps offset the hypertensive effects of sodium.
✓ Seeds and nuts
Pumpkin seeds, sesame seeds, and sunflower seeds score among the highest, with one-quarter cup providing an estimated 48 percent, 32 percent and 28 percent of the RDA of magnesium respectively.
Cashews, almonds, and Brazil nuts are also good sources. One ounce (28-grams) of cashews contains 82 mg of magnesium, which equates to about 20 percent of the RDA.
✓ Fatty fish
Interestingly, fatty fish such as wild caught Alaskan salmon and mackerel are also high in magnesium. A half fillet (178 grams) of salmon can provide about 53 mg of magnesium, equal to about 13 percent of the RDA.
One cup of winter squash provides close to 27 mgs of magnesium; about 7 percent of your RDA.
✓ Herbs and spices
Herbs and spices pack lots of nutrients in small packages, and this includes magnesium. Some of the most magnesium-rich varieties are coriander, chives, cumin seed, parsley, mustard seeds, fennel, basil and cloves.
✓ Fruits and berries
Ranking high for magnesium are: papaya, raspberries, tomato, cantaloupe, strawberries, and watermelon. For example, one medium sized papaya can provide nearly 58 grams of magnesium.
When Supplementing, Balance Your Magnesium with Calcium, Vitamin K2 and D
One of the major benefits of getting your nutrients from a varied whole food diet is that you're less likely to end up with lopsided nutrient ratios. Foods in general contain all the cofactors and needed co-nutrients in the proper ratios for optimal health. Essentially, the wisdom of Mother Nature eliminates the guesswork. When you rely on supplements, you need to become savvier about how nutrients influence and interact with each other in order to avoid getting yourself into trouble.
For example, it's important to maintain the proper balance between magnesium, calcium, vitamin K2, and vitamin D. These four nutrients work together synergistically, and lack of balance between them is why calcium supplements have become associated with increased risk of heart attacks and stroke, and why some people experience vitamin D toxicity.
Unfortunately, we don't yet know the precise ideal ratios between all of these nutrients, but some general guidelines and considerations include the following:
- The ideal ratio between magnesium and calcium is currently thought to be 1:1. Keep in mind that since you're likely getting far more calcium from your diet than you are magnesium, your need for supplemental magnesium may be 2 to 3 times greater than calcium
- While the ideal or optimal ratios between vitamin D and vitamin K2 have yet to be determined, Dr. Kate Rheaume-Bleue (whom I've interviewed on this topic) suggests that for every 1,000 IU's of vitamin D you take, you may benefit from about 100 micrograms (mcg) of K2, and perhaps as much as 150-200 mcg.
- As for how much vitamin D you need, I strongly recommend getting your vitamin D level tested twice a year (summer and winter) to help determine your personal dosage. Sun exposure is the ideal way to optimize your levels, but if you opt for a supplement, your "ideal dosage" is one that will put you into the therapeutic range of 40 to 60 ng/ml.
If Your Health and Energy Levels are Flagging, You May Need More Magnesium
Remember, your need for magnesium can be magnified by factors such as advancing age, stress, lack of sleep, alcohol consumption, insulin resistance and diabetes, prescription drug use, an unbalanced gut microbiome, poor kidney function, and more. If you have any of these risk factors, or if you eat a lot of processed foods, you may want to a) reconsider your diet and b) consider taking a magnesium supplement.
Also remember that while it's best to get your magnesium from your diet, many foods are likely to be deficient in magnesium and other minerals due to being grown in mineral-depleted soils. Fertilizers like glyphosate actually act as chelators, effectively blocking the uptake and utilization of minerals.
As a result, I believe it would be prudent for most people to consider a magnesium supplement. Alternatively, juice your vegetables, which will allow you to consume FAR more of them than you ever could if you ate them whole.
Personally, even though I eat organic and juice regularly, I still take a magnesium supplement. Another strategy that can help improve your magnesium status is to take regular Epsom salt baths or foot baths. Epsom salt is a magnesium sulfate that can absorb into your body through your skin.