Magnesium supplement health benefit, dosage, use for heart disease
August 15 2018 by
Ray Sahelian, M.D.

Magnesium is the fourth most abundant mineral in the body and is essential to good health. Approximately 50% of total body magnesium is found in bone. The other half is found predominantly inside cells of body tissues and organs. Only 1% of magnesium is found in blood, but the body works very hard to keep blood levels of magnesium constant. The RDA for magnesium is about 300 mg. A magnesium supplement can be purchased in health food stores, in drug stores, or on the internet.

Deficiency or low intake symptoms
Feeling tired and noticing weird muscle cramps that are throwing off your workouts? You might be suffering from a magnesium deficiency. This mineral is involved in over 300 biochemical reactions in your body. It affects everything from your heartbeat to your muscles to your hormones.

MultiVit Rx is a High Quality Daily MulitiVitamins and Minerals with Magnesium mineral

Supplement Facts:
Vitamin A - Beta Carotene and Retinyl Palmitate
Vitamin C with Rose hips (ascorbic acid)
Vitamin D
Vitamin E (mixed tocopherols)
Vitamin B-1(thiamine hcl)
Vitamin B-2 (riboflavin)
Vitamin B-6
Folic acid
Vitamin B12
Biotin vitamin
Pantothenic acid (d-calcium pantothenate)
Calcium (citrate)
Iodine (potassium iodine)
Magnesium (oxide)
Zinc (oxide)
Selenium (amino acid chelate)
Copper (amino acid chelate)
Manganese (carbonate)
Chromium (amino acid chelate)
Molybdenum (amino acid chelate)
Potassium (carbonate)
Green Tea (leaves)
Inulin (Jerusalem artichoke plant fiber extract - inuflora)
PABA (para aminobenzoic acid)
Citrus Bioflavonoid Complex
Choline (bitartrate)
Betaine (HCI)
Beta Glucan- 1/3-Beta, 1/6-Glucan (insoluble form from cell walls of Saccharomyces cerevisiae)
Lycopene (from tomato)
Lutein (from marigold extract)
Other ingredients:  Oregano, Cloves, Cinnamon, Alfalfa, Watercress, Parsley, Hawthorne berry, Rice Bran, Lecithin, Silica, Cholesterol free Magnesium Stearate and Stearic Acid. In a base of Inuflora.

Types of magnesium supplements
There are quite a number of different types that are available, including the following:
Magnesium sulfate - citrate (used as laxative) - oxide - chloride - stearate (usually found as one of the fillers and binders in capsules) - hydroxide (used as antacid) - glycinate - carbonate - taurate - gluconate - orotate - L-aspartate hydrochloride, and lactate.
   Magnesium sulfate (also spelled as sulphate) is administered intravenously in hospitals.

I have an aunt that use to get a supply of pidolate de magnesium from France from a family who traveled there frequently. It seems to be called magnesium picolinate in the USA. Do you have it available for sale?
    I am not very familiar with this form of the mineral.

Magnesium orotate dihydrate is poorly soluble in water and hence does not bind gastric acid nor does it exhibit noteworthy laxative effects upon oral administration in contrast to easily dissociable magnesium salts. As a source of magnesium, it is indicated for the oral treatment of extracellular magnesium deficiency. Orotic acid, the second active ingredient of magnesium orotate, is an intermediate in the biosynthetic pathway of pyrimidines and is shown to improve the energy status of injured myocardium by stimulating, a.o., the synthesis of glycogen and ATP. Myocardial energy-rich phosphate levels are decreased during hypoxic conditions; subsequently, intracellular magnesium is depleted and lost via the urine.

Which form is best?
The most common forms that are ingested as supplements include magnesium chelate, citrate, aspartate, and oxide. Magnesium powder is also available for sale.
There is a controversy regarding the ideal form to be taken as a supplement. Although there may be variations in absorption rates of different forms, I am not sure, for practical purposes, if it makes much of a difference in the long run. Sometimes dosages of supplements that people take are very high, and it may be preferable that less is absorbed. Each case and each person is different, so I can't make any generalizations. One study shows citrate and chelate are better absorbed, but red blood cell levels of magnesium were found to be equal with all three forms. As you can see by the number of studies listed below, various forms all appear to have therapeutic benefits.

Magnesium citrate found more bioavailable than other Magnesium preparations in a randomised, double-blind study.
Magnes Research. 2003.
In this 60 day study, the relative bioavailability of three preparations of magnesium (amino-acid chelate, citrate and oxide) were compared at a daily dose of 300 mg of elemental Mg in 46 healthy individuals. Results showed that supplementation of the organic forms of magnesium (citrate and amino-acid chelate) showed greater absorption at 60 days than oxide. Magnesium citrate led to the greatest mean serum magnesium concentration compared with other treatments. The red blood cell magnesium concentration showed no differences among groups. Chronic magnesium citrate supplementation resulted in the greatest magnesium concentration in saliva.
   My comments: As far as treatment of medical conditions, it appears many different forms have similar benefits. A few paragraphs below there is a study regarding the benefit of magnesium oxide for heart failure. Therefore, for practical purposes, I am not sure if one form is superior to another form. One option is to take various forms of magnesium supplements as opposed to just one form.

Is it true that magnesium oxide is form that doesn’t absorb well?
   It is absorbed sufficiently to have an effect on bone mineral content.

Ter Arkh. 2015. Meta-analysis of clinical trials of cardiovascular effects of magnesium orotate. The use of magnesium orotate is promising not only in treating MVP mitral valve prolapse and compensating for hypomagnesemia, but also in preventing and treating cardiac arrhythmias, regulating blood pressure, and improving the function of the autonomic nervous system.

Food: Magnesium content in diet
Magnesium rich foods -- Green vegetables such as spinach are good sources because the center of the chlorophyll molecule (which gives green vegetables their color) contains magnesium. Other foods high in magnesium include legumes (beans and peas), nuts and seeds. Whole, unrefined grains are also good sources. Refined grains are generally low in in this mineral. When white flour is refined and processed, the magnesium -rich germ and bran are removed. Dietary magnesium is absorbed in the small intestines. The mineral is excreted through the kidneys.
Hard water is also considered to be an important source of magnesium beneficial to human health.

Benefit and medical uses
Magnesium is needed for more than 300 biochemical reactions in the body. It helps maintain normal muscle and nerve function, keeps heart rhythm steady, supports a healthy immune system, and keeps bones strong. It also helps regulate blood sugar levels, promotes normal blood pressure, and is known to be involved in energy metabolism and protein synthesis. There is an increased interest in its role in preventing and managing disorders such as hypertension, cardiovascular disease, and diabetes. Those with higher levels seem to have a lower risk of sudden cardiac death. Magnesium may even help some individuals who have migraine headache.

Rocz Panstw Zakl Hig. 2013. Magnesium: its role in nutrition and carcinogenesis. Mg plays a key role in many essential cellular processes such as intermediary metabolism, DNA replication and repair, transporting potassium and calcium ions, cell proliferation together with signaling transduction. The daily dietary intake of magnesium is frequently found to be below that recommended in Western countries. Indeed, it is recognised that magnesium deficiency may lead to many disorders of the human body, where for instance magnesium depletion is believed to play an important role in the etiology of the following; cardiovascular disease (including thrombosis, atherosclerosis, ischemic heart disease, myocardial infarction, hypertension, arrhythmias and congestive heart failure in human), as well as diabetes mellitus, gastrointestinal (GI) tract disease, liver cirrhosis and diseases of the thyroid and parathyroid glands. Insufficient dietary intake of magnesium may also significantly affect the development and exacerbation of ADHD (Attention Deficit- Hyperactivity Disorder) symptoms in children.

Anxiety reduction, relaxation, does it help with sleep?
Q. I have started to take Natural Vitality Calm Magnesium citrate with excellent results so far. I have noticed a relaxation of mind and body which I feel is needed for someone with stress and anxiety. Is Magnesium citrate the form you would recommend for anxiety, long term use, etc.? What about the dosage and type of supplement (powder, capsule, tablet, etc.)? I was thinking of taking approximately 160 mg of the Magnesium citrate a day for 5 or 6 days per week.
   A. I think different types work well enough so there is no need to be very specific.

On Fox News in June 2015 a doctor said that taking a magnesium supplement before bed was good for sleep, is this true?
   In my experience this mineral does not have much of an effect on treating insomnia, although some people may notice a very mild effect on sleep induction.

Bone mineral density, osteoporosis
A higher intake of magnesium from food and supplements may keep bones healthy as people age, according to results of a study in Journal of the American Geriatrics Society which suggests that greater magnesium intake is significantly related to higher bone mineral density (BMD) in white men and women. According to the paper, there was an approximate 2 percent increase in whole-body BMD for every 100 milligram per day increase in magnesium. Higher magnesium intake through dietary change or supplementation may provide an additional strategy for the prevention of osteoporosis but results of studies are conflicting.

Am J Clin Nutr. 2014. Magnesium intake, bone mineral density, and fractures: results from the Women's Health Initiative Observational Study. Lower magnesium intake is associated with lower BMD of the hip and whole body, but this result does not translate into increased risk of fractures.

A randomized controlled study of effects of dietary magnesium oxide supplementation on bone mineral content in healthy girls.
J Clin Endocrinology Metabolim. 2006.
Limited studies suggest that dietary magnesium intake and bone mineral density are correlated in adults, but no data from interventional studies in children and adolescents are available. We sought to determine whether Mg supplementation in periadolescent girls enhances accrual of bone mass. We carried out a prospective, placebo-controlled, randomized, one-year double-blind trial of Mg supplementation. Healthy 8- to 14-yr-old Caucasian girls were recruited from community pediatricians' offices. Dietary diaries from over 120 volunteers were analyzed, and those with dietary Mg intake of less than 220 mg/d were invited to participate in the intervention. Magnesium (300 mg elemental magnesium per day in two divided doses) or placebo was given orally for 12 months. Significantly increased accrual in integrated hip bone mineral content occurred in the Mg-supplemented vs. placebo group. Serum mineral levels, calciotropic hormones, and bone markers were similar between groups. Oral Mg oxide capsules are safe and well tolerated.

Magnesium intake from food and supplements is associated with bone mineral density in healthy older white subjects.
J Am Geriatric Soc. 2005. Department of Medicine, Health Science Center, University of Tennessee, Memphis, Tennessee
Greater magnesium intake was significantly related to higher BMD in white women and men. The lack of association observed in black women and men may be related to differences in calcium regulation or in nutrient reporting.

Cancer, tumor
High levels in the diet may lower a woman's risk of developing colon cancer but it is difficult to tell whether the benefit is due to magnesium intake rather than some related factor. Magnesium has been hypothesized to cut the risk of colon cancer by reducing oxidative stress, improving insulin sensitivity, or through mechanisms that reduce proliferation of cells in the colon. American Journal of Epidemiology, 2006.

Diabetes and blood sugar problems
Those who consume a good amount of this mineral in their diet are less likely to have high blood sugar levels and less likely to have diabetes in the future.

Clinical efficacy of magnesium supplementation in patients with type 2 diabetes.
J Am Coll Nutrition. 2004.
Effects of magnesium supplementation on nine mild type 2 diabetic patients with stable glycemic control were investigated. Water from a salt lake with a high natural Mg content (7%) (MAG21) was used for 30 days. Fasting serum immunoreactive insulin level decreased significantly. There was also a marked decrease of the mean triglyceride level after supplementation. The patients with hypertension showed significant reduction of systolic, diastolic, and mean blood pressure. The salt lake water supplement, MAG21, exerted clinical benefit as a Mg supplement in patients with mild type 2 diabetes mellitus.

Oral magnesium supplementation improves insulin sensitivity and metabolic control in type 2 diabetic subjects: a randomized double-blind controlled trial.
Diabetes Care. 2003.
A total of 63 subjects with type 2 diabetes and decreased serum magnesium treated by glibenclamide received either 50 ml magnesium chloride solution (containing 50 g magnesium chloride per 1,000 ml solution) or placebo daily for 16 weeks. Oral supplementation with magnesium chloride solution restores serum levels, improving insulin sensitivity and metabolic control in type 2 diabetic patients.

DNA damage prevention
Oxid Med Cell Longev. 2016. Magnesium Supplementation Diminishes Peripheral Blood Lymphocyte DNA Oxidative Damage in Athletes and Sedentary Young Man. The aim of this study was to determine whether four-week-long magnesium supplementation in students with sedentary lifestyle and rugby players could prevent or diminish impairment of DNA. Our study demonstrated that the number of peripheral blood lymphocytes (PBL) with basal endogenous DNA damage is significantly higher in rugby players compared to students with sedentary lifestyle. On the other hand, magnesium supplementation significantly decreased the number of cells with high DNA damage. The results of our study suggest that four-week-long magnesium supplementation has marked effects in protecting the DNA from oxidative damage in both rugby players and in young men with sedentary lifestyle.

Drug abuse reduction
A preliminary, controlled investigation of magnesium L-aspartate hydrochloride for illicit cocaine and opiate use in methadone-maintained patients.
J Addict Dis. 2003.
Eighteen methadone-maintained patients who used illicit opiates and cocaine received either Mg (732 mg/day) or placebo for 12 weeks. The preliminary findings suggest that magnesium may have a beneficial effect for reducing illicit opiate use.

Exercise, physical endurance, activity
Daily magnesium oxide supplementation for 12 weeks seems to improve physical performance in healthy elderly women. These findings suggest a role for magnesium supplementation in preventing or delaying the age-related decline in physical performance. Effect of oral magnesium supplementation on physical performance in healthy elderly women involved in a weekly exercise program: a randomized controlled trial. Am J Clin Nutr 2014.

Heart failure treatment, role in heart disease
Acute and chronic oral magnesium supplementation: effects on endothelial function, exercise capacity, and quality of life in patients with symptomatic heart failure.
Congest Heart Fail. 2006. Fuentes JC, Salmon AA, Silver MA. Department of Medicine and Heart Failure Institute, Advocate Christ Medical Center, Oak Lawn, IL 60453, USA.
The objective of this study was to determine the effects of acute and chronic oral magnesium supplementation on endothelial function in patients with symptomatic heart failure. Twenty-two symptomatic chronic heart failure patients were randomized to receive 800 mg oral magnesium oxide daily or placebo for 3 months. Patients who received magnesium had improved small arterial compliance at 3 months from baseline compared with placebo.

Heart disease
Effects of oral magnesium therapy on exercise tolerance, exercise-induced chest pain, and quality of life in patients with coronary artery disease.
Am J Cardiol. 2003. The Heart Institute, Sheba Medical Center, Tel Hashomer, Israel.
Patients with coronary artery disease were randomized to receive either oral magnesium 15 mmol twice daily (Magnosolv-Granulat, total magnesium 365 mg provided as magnesium citrate) or placebo for 6 months. Oral magnesium citrate supplementation in patients with coronary artery disease for 6 months results in a significant improvement in exercise tolerance, exercise-induced chest pain, and quality of life.

Oral magnesium supplementation in adults with coronary heart disease or coronary heart disease risk.
J Am Acad Nurse Pract. 2009.
There were no reports of adverse effects from magnesium supplementation in any of the studies. Subjects reporting lower dietary magnesium intake had significantly lower serum magnesium concentrations than those reporting higher dietary intake and, in some cases, had a significantly higher frequency of supraventricular beats  There is a possible association between a modestly lower risk of CHD in men and increased magnesium intake; therefore, it is reasonable to encourage diets high in magnesium as a potential means to lower the risk of CHD.

Urinary and plasma magnesium and risk of ischemic heart disease.
Am J of Clinical Nutrition, 2013.
An increased dietary intake of magnesium, particularly in those with the lowest urinary magnesium, could reduce the risk of IHD.

Oral magnesium supplementation inhibits platelet-dependent thrombosis in patients with coronary artery disease.
Am J Cardiology. 1999.

Heart rhythm
Magnesium as an anti-arrhythmic therapy principle in supraventricular and ventricular cardiac arrhythmias
Z Kardiol 1996.
The use of magnesium as an antiarrhythmic agent in ventricular and supraventricular arrhythmias is a matter of an increasing but still controversial discussion during recent years. With regard to the well established importance of magnesium in experimental studies for preserving electrical stability and function of myocardial cells and tissue, the use of magnesium for treating one or the other arrhythmia seems to be a valid concept. In addition, magnesium application represents a physiologic approach, and by this, is simple, cost-effective and safe for the patient. However, when one reviews the available data from controlled studies on the antiarrhythmic effects of magnesium, there are only a few types of cardiac arrhythmias, such as torsade de pointes, digitalis-induced ventricular arrhythmias and ventricular arrhythmias occurring in the presence of heart failure or during the perioperative state, in which the antiarrhythmic benefit of magnesium has been shown and/or established. Particularly in patients with one of these types of cardiac arrhythmias, however, it should be realized that preventing the patient from a magnesium deficit is the first, and the application of magnesium the second best strategy to keep the patient free from cardiac arrhythmias.

Mitral Valve Prolapse
Magnesium may be beneficial in mitral valve prolapse.

High blood pressure, hypertension
Oral magnesium supplements decrease high blood pressure (SBP > 155mmHg) in hypertensive subjects on anti-hypertensive medications: a targeted meta-analysis. Magnes Research, August 1, 2013.

Magnesium dilates arteries, and in doing so lowers blood pressure.

Sleep and insomnia
J Res Med Sci. 2012. The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial. A double-blind randomized clinical trial was conducted in 46 elderly subjects, randomly allocated into the magnesium or the placebo group and received 500 mg magnesium or placebo daily for 8 weeks. Supplementation appears to improve subjective measures of insomnia such as ISI score, sleep efficiency, sleep time and sleep onset latency, early morning awakening, and likewise, insomnia objective measures such as concentration of serum renin, melatonin, and serum cortisol, in elderly people.

Dietary magnesium intake is inversely associated with risk of stroke, specifically ischemic stroke. American Society for Nutrition, 2012.

Magnesium deficiency
Severe magnesium deficiency is not common in the United States, however there may be many people who go on with their lives with marginal magnesium deficiency. Early signs of moderate magnesium deficiency include loss of appetite, nausea, vomiting, fatigue, and weakness. As magnesium deficiency becomes more severe, numbness, tingling, muscle contractions and cramps, seizures, personality changes, abnormal heart rhythms, and coronary spasms can occur.
   Magnesium deficiency resulting from feeding a diet that has a third of the recommended magnesium intake induces heart arrhythmias, impairs glucose balance, and alters cholesterol metabolism. J Am Coll Nutr. 2007.

Use with calcium
Is it important to take magnesium and calcium supplements at separate (differing) times of the day?
   There is no simple answer. It may depend on your overall health, absorption capacity, condition being treated, use with food or empty stomach, types of food taken with, dosage of the minerals, medications you may be using, other supplements taken at the same time or at other times of day, and other factors. The most practical option is to at times take them together and at other times to take them separately.

Research studies
For children who need to go to the ER because of a severe asthma attack, giving them an intravenous infusion of magnesium sulphate along with conventional medications provides an additional benefit.

I notice that the multi vitamin formula contains magnesium oxide. I was reading that it is inferior to other compounds such as chloride and lactate. Is this accurate?
   Since there have never been long term human studies comparing the different forms of magnesium, it is premature to say that one form is better or inferior than another form.

I recently read a claim that taking the recommended supplementation of 1000-1200 mg Calcium, especially without magnesium supplementation, is too high a dose of calcium and leads to kidney stone, Ca crystal deposits in joints, etc. This source claimed that one should take less Ca and an equal amount of Magnesium ...and if you purchase their newsletter, they will tell you how much of each you should take. Any credence to this? And if so, what is the ratio of Calcium Magnesium? Personally, I do not respect a source that poses such a tease and then doesn't answer it unless you pay. I appreciate the quality of the information you provide in your newsletter, especially your candor re: evaluation of research data and journal articles. Having been in research, I know the ways data are mainupulated to please funding sources and get grant renewals. Unfortunately, most lay people still view "scientific research" as gospel.
   Thank you for your good question. Scientists are still trying to prove that calcium supplements do work to strengthen bones, and this claim seems to have a good confidence of being accurate. We have not seen any studies on the combination of calcium and magnesium to know whether this is better for bones. Since we don't even know the answer to this simple question, it remains to be seen what the ratios should be. There's not enough research to know the ideal calcium magnesium ration. My thought would be if someone were to supplement their diet with calcium and magnesium, an educated guess would be between 500 to 1000 mg of calcium and 100 to 300 mg of magnesium.

I'm confused: can magnesium and calcium be taken together? If they counteract each other, why are there cal/mag supplements? Please advise because I'd like to take magnesium to help my depression and fatigue, but read either contradictory advice as to whether calcium should be taken with it or not.
   As a general rule, we don't see why magnesium and calcium can't be taken together.

What is magnesium ascorbyl phosphate, have you heard of it?
   Magnesium ascorbyl phosphate is a bleaching agent used in cosmetic products.

I saw an article online in which Dr. Sahelian speaks of magnesium for helping reduce hypertension. A Japanese researcher was sited and the magnesium was referred to as mg (OH)2. Could you explain what the OH2 is? I searched but couldn't find an answer. Also, does Dr. Sahelian consider magnesium as the most effective supplement for hypertension? What about hawthorne?
   OH2 stands for hydroxide, it is one of the forms magnesium is sold. Magnesium may help some people with high blood pressure but in order to reduce hypertension, a comprehensive dietary and lifestyle program should be initiated. See hypertension for more info.

I have just read some of your e-mails on magnesium and I was wondering what is the difference between magnesium stearate and the other types of magnesium. I used to use magnesium stearate (suggested by a doctor) to help me relax so I could get good sleep. It also helped me with muscle tension and stiffness. Well I can no longer find magnesium stearate. I've tried using citrate and oxide but they don't help like the stearate did.
   Magnesium stearate is formed by stearate (the anion of stearic acid) and magnesium. Magnesium stearate is used as a filling agent in the manufacture of nutritional tablets since it prevents ingredients from sticking to manufacturing equipment during the making of capsules and tablets. We have not come across magnesium stearate sold as a form of a magnesium supplement in capsule form.

What is the usual starting dose?
    The usual staring dosage for a magnesium supplement can range from 100 to 200 mg.

You discuss magnesium and it doesn’t matter about what type, but in her book Dr Carolyn Dean M.D. N.D. “ The Miracle Magnesium” says that plenty of research she and others has done tells that magnesium oxide it was found only is absorbed to the tune of about 4% so a 400 mg dose for example would only be about 16 mg absorbed. She says the best is magnesium citrate for bio-availability, so who is right and who isn’t doing research?

Is there any advantage to taking ionic magnesium rather than other forms of magnesium supplements?
   I am not aware of any studies that indicate ionic magnesium is superior to other forms.

Does magnesium help with erythromelalgia?
   As of 2013, I have not seen such studies.

Love your site, great reliable information. I have a question regarding magnesium oil. Does it significantly aid in restoring a magnesium deficiency? I have read that through oral supplementation it can take up to 2 years to rectify a severe deficiency in magnesium. Does magnesium oil offer any genuine advantages over oral supplementation?
    I have not seen any studies with magnesium oil. There are certain web sites that claim rubbing this oil in the skin restores deficiencies and is superior to oral ingestion of pills, but I have not come across any such research. A deficiency of magnesium can be reversed with oral pills in days or weeks rather than years.

I have a question about magnesium pills. I take a pill every night before bedtime and give one to my husband as well. Yesterday I was told that it helps people with headaches. My husband has a spinal problem and wakes up in the morning always with a headache because of his bad neck. I was told yesterday to give him magnesium pills 3 times daily and perhaps it would help his headaches. Can you kindly touch on magnesium in your next newsletter and perhaps talk about the benefits and how much most of us need to take on a daily basis, especially those of us with muscular and arthritic problems.
    Headaches are caused by multiple factors and magnesium product use is rarely an adequate solution.

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Magnesium is an essential mineral, playing a key role in over 300 enzymatic reactions in metabolism. Magnesium is involved in energy production and storage, the breakdown of fatty acids, protein synthesis, DNA metabolism, the relaxation of both voluntary and involuntary muscle tissue, neuro-transmitter activity, and hormone regulation. Magnesium is stored primarily in the bones, and along with other minerals, plays a role in the metabolism of bone.
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Supplement Facts
Serving Size: 2 tablets
Servings per Container: 60 servings
  Amount per serving % Daily Value
Magnesium (elemental) (from 2,000 mg magnesium glycinate/lysinate chelate**) 200 mg 50%

Suggested Use: one magnesium tablet daily, or every other day, with meals, or as recommended by your health care professional.
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