Magnesium is one of seven essential macrominerals important for overall health. Although many foods contain magnesium, you may need to take a supplement to boost your intake. Many forms of magnesium supplements are available, so it's useful to know which are best for the condition you are treating and which are the most bioavailable to your body.
Boosting your magnesium level with a liquid supplement may help with digestive disorders, high blood pressure, irregular heartbeat, anxiety and depression, muscle soreness and migraine headaches.
Magnesium Benefits to Your Body
Magnesium is an electrolyte and cofactor to over 300 enzymes that modulate many biochemical functions in your body, such as regulating your heartbeat rhythm and controlling neurotransmitters needed to help cells communicate. Magnesium is also necessary for converting fats and carbs to energy for the proper functioning of your brain, bones, heart and muscles.
Read more: The Benefits of the Magnesium Mineral
Your Magnesium Requirements
Your body loses stores of magnesium on a daily basis from normal processes such as muscle movement, heartbeat and hormone production. Although you need only a small quantity of magnesium, it's important to get a sufficient amount to maintain good health.
The National Institutes of Health recommends the following daily dietary allowances for magnesium:
- Adults, ages 19 to 30: men, 400 milligrams; women, 310 milligrams
- Adults, ages 31 and older: men, 420 milligrams; women, 320 milligrams
- Pregnant women: 350 to 400 milligrams, depending on age
Symptoms of Magnesium Deficiency
The majority of Americans eat diets that supply less than the recommended amount of magnesium. Low magnesium levels can result from chronic alcoholism, certain health conditions that prevent the absorption of minerals, or from using certain medications, all of which can put you at greater risk of a deficiency.
If you are deficient in magnesium, you may experience some of these early warning signs;
- Loss of appetite
- Nausea and vomiting
- Fatigue and weakness
As the deficiency progresses, symptoms may include:
- Numbness and tingling
- Muscle contractions or cramps
- Personality changes
- Irregular heart rhythms and spasms
Severe magnesium deficiency can result in low calcium or potassium levels, leading to hypomagnesemia, with more severe symptoms such as:
- High blood pressure and cardiovascular disease
- Kidney and liver damage
- Migraine headaches, multiple sclerosis, glaucoma or Alzheimer's disease
- Nutrient deficiencies, including thiamin, vitamin K, calcium and potassium
- Restless leg syndrome
- Worsened PMS symptoms
- Behavioral disorders and mood swings
- Insomnia and trouble sleeping
- Fungal or bacterial infections from low levels of nitric oxide or a compromised immune system
- Preeclampsia and eclampsia
A deficiency of magnesium is also linked to insulin resistance, heart disease, metabolic syndrome and osteoporosis, according to Medical News Today.
Food Sources of Magnesium
Magnesium is found in many foods, but only about 30 to 40 percent of dietary magnesium is absorbed by your body. When wheat is refined, much of its magnesium content is lost, so it's best to choose whole grains. Generally, foods high in dietary fiber contain magnesium. Many common fruits, meat and fish are low in magnesium.
Some especially good choices of foods containing magnesium include:
- Nuts and seeds such as almonds, cashews, sunflower seeds
- Dark green vegetables, such as spinach, kale, broccoli
- Whole grains such as brown rice, oatmeal, whole-wheat bread
- Legumes, such as black beans, kidney beans
- Soy products, such as edamame, soy milk
- Fortified foods, such as cereals, health bars
Types of Magnesium Supplements
Since many vitamins, minerals and phytonutrients work synergistically, it's always better to get magnesium from your diet rather than from a supplement. However, if you can't get enough magnesium from food, or have a condition that requires a high dosage, supplements are available in a variety of forms.
You can take magnesium supplements by tablet, chewable form, gel cap, topical oils, soluble salts and oral liquid magnesium drops. The magnesium drops form of supplement is ideal for infants and toddlers or for anyone who has trouble swallowing pills.
Magnesium is sold over-the-counter as individual supplements or included in multivitamins and in medications, such as antacids and laxatives. Magnesium is combined with different compounds for supplemental use and some of those that are best absorbed include:
- Magnesium chelate: Highly absorbable and the type found in foods naturally bound to multiple amino acids.
- Magnesium citrate: Magnesium in combination with citric acid. With its excellent bioavailability, it's used to improve digestion and prevent constipation, but can have a high laxative effect.
- Magnesium chloride: Possibly the most popular magnesium supplement on the market. It is organic and available in a liquid magnesium oil form that can even be applied to the skin. The oil is useful for preventing absorption disorders in the stomach. In addition, magnesium chloride oil is good for healing wounds and skin irritations. It also encourages sleep, aids digestion, promotes bone health and helps provide a sense of calm.
- Magnesium glycinate: Highly absorbable. Most often used to treat magnesium deficiency without laxative side-effects. This is the best form to support muscle relaxation and calming effects.
- Magnesium threonate: Highly bioavailable and easily absorbed by penetrating the mitochondrial membrane. This form has the potential to improve cognitive function.
- Magnesium orotate: Contains orotic acid (B13) and magnesium orotate. This organic supplement is used to benefit the heart, repair tissue and enhance performance and stamina.
- Magnesium carbonate: Most commonly reported to cause diarrhea.
- Magnesium sulfate: Otherwise known as epsom salts, this form is used in solution for its laxative effects and to relieve sore muscles.
Absorption and Bioavailability
The degree to which magnesium is absorbed and retained for use by your body differs among the various forms. The types that dissolve in liquid are better absorbed in the gut than are less soluble forms.
For a magnesium deficiency, a reversal can be achieved more quickly with topical sprays, oils, liquid magnesium and epsom salts. Magnesium glycinate, threonate, orate, citrate and chloride forms are absorbed more quickly and are more bioavailable to your body than other forms of magnesium.
If taking supplements, be aware that taking high doses of zinc or vitamin D or being deficient in vitamin K2 can interfere with the balance of magnesium. It's best to use food-based organic supplements and consider that calcium and magnesium interact with one another, so keep your calcium levels up when taking magnesium.
Magnesium Side Effects
It is unlikely you will have any side effects from too much magnesium from food, but supplements may cause digestive upsets, including stomach ache, nausea, diarrhea and vomiting. Therefore, you should not take magnesium supplements on an empty stomach.
The forms of magnesium most often reported to cause diarrhea are carbonate, chloride, gluconate and oxide. This effect is due to the osmotic activity of unabsorbed salts in the digestive tract.
Read more: Pros & Cons of Magnesium Supplements
Toxicity and Interactions
The tolerable upper level for magnesium is 350 milligrams for adults. Doses providing more than 5,000 milligrams a day have been associated with toxicity, including hypermagnesemia, with symptoms including:
- Urine retention
- Low blood pressure
- Irregular heartbeat
- Difficulty breathing
- Muscle weakness
- Cardiac arrest
- Bisphosphonates, such as those to treat osteoporosis
- Proton pump inhibitors
Magnesium for Bone Health
Of the 25 grams of magnesium in your body, 50 to 60 percent is stored in your skeletal system. Magnesium helps assimilate calcium into your bones and plays a role in activating vitamin D, also essential for healthy bones.
A study published by the International Journal of Endocrinology in 2018 reported that low levels of magnesium are associated with low bone density in both pre- and postmenopausal women. Magnesium intake led to increased bone density in people of all ages and was found to possibly reduce the risk of osteoporotic fractures.
Magnesium as a Laxative
Magnesium is useful to relieve constipation because it helps relax muscles in the digestive tract and also neutralizes stomach acid. Magnesium is often used to prepare the bowels for surgical or diagnostic procedures.
A primary ingredient in many laxatives is liquid magnesium. For example, Phillips' Milk of Magnesia contains 500 milligrams of elemental magnesium per tablespoon. A dose is up to 4 tablespoons daily.
WebMD says the dosage for constipation using magnesium sulfate (epsom salts) is 10 to 30 grams in a liquid solution of 8 ounces of water.
Magnesium for Heart Health
Another one of magnesium benefits is its contribution to your cardiovascular system. Magnesium supplements are used for treating disorders of the heart and blood vessels, including angina, irregular heartbeat, hypertension, metabolic syndrome, clogged arteries, stroke and high cholesterol levels, according to WebMD.
Patients who receive magnesium soon after a heart attack may reduce their risk of mortality, says Medical News Today. The Framingham Heart Study showed magnesium intake is associated with a lower risk of atherosclerosis, which is a fatty buildup on the walls of your arteries causing high blood pressure and the risk of stroke.
The study, published in JACC Cardiovascular Imaging in 2015, found that those with a high intake of magnesium had a 58-percent reduced chance of coronary artery calcification and a 34-percent lowered risk of abdominal artery calcification. Results suggested that magnesium may offer protection from stroke and fatal coronary heart disease.
Magnesium for Headaches
Migraines and other types of headaches are often promoted by a deficiency in magnesium, which plays a role in neurotransmitter release and vasoconstriction. The National Institutes of Health reported that people who experience migraine headaches have lower magnesium levels than those who do not.
A study in 2014 evaluated and compared the effects of magnesium sulfate supplementation to a commonly used medication for the treatment of migraine headaches. Findings, published in the Journal of Emergency Medicine found that the group given magnesium sulfate had faster, more effective pain relief than the combination of medications typically used for migraine treatment.
Read more: Headaches and Migraines
Anxiety, Depression and Sleep Disorders
If you find you cannot sleep because of stress, anxiety or depression, you may have low levels of magnesium. Magnesium helps quiet nerve activity by maintaining healthy levels of GABA, a neurotransmitter that promotes sleep, according to the Sleep Doctor. Magnesium can also help insomnia that's linked to restless-leg syndrome.
To analyze stress reduction and magnesium intake, researchers administered 400 milligrams of magnesium to patients for 90 days. Findings published in the journal MMW Fortschritte Der Medizin in 2016 reported that people with mental and physical stress can benefit from magnesium to help relieve restlessness, irritability, depression and sleep disorder.
Read more: Major Signs of Depression
- National Institutes of Health: Office of Dietary Supplements: Magnesium
- Dr. Axe: Should You Be Taking Magnesium Supplements?
- Medical News Today: Why Do We Need Magnesium?
- VitaCost: How Do You Know Which Type of Magnesium Is Best for You?
- WebMD: Magnesium
- International Journal of Endocrinology: Magnesium and Human Health: Perspectives and Research Directions
- JACC Cardiovascular Imaging: Magnesium Intake Is Inversely Associated With Coronary Artery Calcification
- Journal of Emergency Medicine: Comparison of Therapeutic Effects of Magnesium Sulfate vs. Dexamethasone/Metoclopramide on Alleviating Acute Migraine Headache
- Sleep Doctor: Magnesium – How It Affects Your Sleep
- Journal MMW Fortschritte Der Medizin: Long-Term HRV Analysis Shows Stress Reduction by Magnesium Intake