What Is The Best Magnesium Supplement For You? A Simple Guide to Choosing

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    In this article, we’ll discuss the types of magnesium supplements available, possible health benefits, and how to determine the quality that meets your needs.

    When you’re looking for a magnesium supplement, the number of options can quickly get overwhelming. There are many forms of magnesium, and while they all contain the same mineral, the different formulations can have various uses. In this article, we’ll discuss the types of magnesium supplements available, possible health benefits, and how to determine the quality that meets your needs.

    What Are The Different Types of Magnesium Supplements?

    Magnesium is a mineral that is needed for many aspects of health. Magnesium supplements are not all the same. Many times, they use different forms of the nutrient. What does this mean for absorption and overall effectiveness? The most common varieties of magnesium are discussed below.

    Magnesium Citrate

    Magnesium citrate binds the mineral to citric acid, which naturally comes from citrus fruits. This is one of the most common and widely available forms of magnesium. It can be helpful for supporting magnesium intake.

    Magnesium citrate is considered to be more bioavailable than some other forms. It has a natural laxative effect, so may be used by medical providers to address constipation. For those who find the side effects of diarrhea or loose stools to be uncomfortable, other forms of magnesium are better alternatives.

    Magnesium Oxide

    Magnesium oxide is the mineral paired with oxygen. This form is not used for magnesium nutritional support, since it has a lower bioavailability.

    Magnesium oxide is typically used to address occasional constipation. Even with a lower bioavailability, it’s important to follow recommended intakes. Long-term use of magnesium oxide still has the potential to increase magnesium serum levels.

    Magnesium Glycinate

    Magnesium glycinate combines the mineral with the amino acid glycine. Glycine is an amino acid that is used by the liver to make glutathione, an endogenous (meaning, it’s a compound made entirely in your body) antioxidant. It’s also used to make other proteins in the body.

    Magnesium glycinate is considered a bioavailable form of this mineral, and can help to support nutritional status. It may still have laxative effects, when consumed at higher amounts, although it is generally considered as gentler than magnesium oxide or citrate. Magnesium glycinate may also support vitamin D status, when combined with vitamin D, versus vitamin D alone or placebo.

    Magnesium Chloride

    Magnesium chloride is the mineral paired with the element chlorine, to form a magnesium salt. Magnesium chloride absorbs well and can be used to support a healthy magnesium status. It is a common form found in supplements.

    Magnesium Taurate

    Magnesium taurate is the mineral paired with the amino acid taurine. Taurine supports mitochondrial, metabolic, and energy generating balance in the body. It is also found in higher concentrations in the heart, brain, eyes, and skeletal muscles.

    Magnesium taurate has mostly been studied in animals, and human clinical trials are sparse.

    Magnesium L-Threonate

    Magnesium L-threonate is the mineral combined with threonic acid, which is produced from the breakdown of vitamin C.

    Magnesium threonate is considered to be bioavailable, particularly for supporting magnesium status in neurons and the central nervous system. Studies are limited, and the primary one that shows benefit for brain health paired magnesium L-threonate with phosphatidylserine, vitamin D, and vitamin C, which may have confounded the ability to know which nutrient contributed the beneficial effects. More studies are needed, but magnesium L-threonate is a promising form of this important mineral.

    Magnesium Hydroxide

    Magnesium hydroxide is a pharmaceutical form of the mineral that is found in over-the-counter laxative products, like Milk of Magnesia. It is considered to be a saline laxative and is sometimes recommended by medical providers to address short-term constipation.

    Magnesium hydroxide helps the intestines to retain more water, which can reduce how hard bowel movements are, leading to better frequency and ease of transit in the gut. Consult a medical provider before using a laxative, since constipation can be a sign of more serious health needs.

    Magnesium Lactate

    Magnesium lactate is the mineral paired with lactic acid, the chemical produced by the muscles in response to using carbohydrates for energy. It is easily absorbed although is not a common form used in dietary supplements, though it is used as a food additive or for food fortification.

    Magnesium lactate has not been widely studied for general nutritional support, although a small study found that a slow-release version of this nutrient can support magnesium status.

    Magnesium Sulfate

    Magnesium sulfate is the mineral combined with oxygen and sulfur. It’s typically found in a crystallized salt form, also known as Epsom salt.

    Magnesium sulfate is typically used topically, like in oils or lotions, or dissolved into water for baths or soaks. While it can be consumed internally, it tastes bitter and can be dangerous if consumed improperly. Magnesium sulfate is not considered to effectively support magnesium status, since this has not been proven by research to absorb through the skin.

    How to Choose the Right Magnesium Supplement

    To choose the right magnesium supplement for you, it’s important to know why you need it and the factors that are important to assess overall quality.

    Understand your health needs

    Magnesium as a nutrient supports many aspects of health, from muscles to bones to bowel regularity. While it’s possible to get all of the magnesium that you need from food alone, there are many reasons why a dietary supplement may be recommended.

    You may need a magnesium supplement for any of the following reasons:

    • To support general nutritional intake
    • For healthy gut motility and constipation support
    • As a support for healthy bones

    Your medical provider may suggest a specific form of magnesium, but typically, the reason why you are taking the mineral will inform the type of supplement you choose.

    Possible side effects

    When magnesium is taken as directed, it is generally safe. Since it is often used to support bowel motility, it may also produce side effects like diarrhea, intestinal cramping, and nausea.

    If taken at higher-than-recommended amounts, or greater than 350 mg per day, it can cause loose stools, diarrhea, or other complications.

    Magnesium can interact with some medications, so be sure to tell your medical provider about any medications, OTC medicines, or other supplements that you take.

    Absorption efficiency

    Magnesium forms can have different bioavailability, although most of the commonly available forms have a similar rate of absorption.

    Other things to consider about magnesium absorption:

    • While magnesium does not affect calcium absorption, taking magnesium supplements with calcium supplements may reduce how much magnesium is absorbed.
    • Vitamin D, especially at higher supplemental intakes, may increase magnesium absorption.
    • Higher supplement intakes of zinc might decrease absorption of magnesium or may increase how much magnesium is excreted. This effect is more of a concern for postmenopausal people who have more significant bone density concerns.

    Quality of supplement

    It’s important to evaluate the quality of magnesium supplements.

    • Supplement facts: This tells you how much of the nutrient is found in each serving size.
    • Other ingredients: Most supplements have some additional ingredients, which may include the capsule, antioxidants, preservatives, sweeteners, flavorings, and more. Consider whether any of these are problematic for your health needs.
    • Third-party testing: Brands may choose to have third-party or independent quality, sustainability, or purity tests. This can help to set apart a brand’s quality as well as provide customer assurance of transparency.
    • Allergens: If you have food allergies or sensitivities, be sure to verify that any supplement is free from them. These are usually clearly disclosed on the label, but if you have less common allergens or need additional information, use the brand’s contact information on the label to get more information.
    • Values: Whether you are vegan, vegetarian, or want a non-GMO product, brand values and manufacturing standards can impact whether or not a supplement is right for you. You can get this info by reading labels closely and by learning more about the supplement manufacturer on their website.

    What are the Health Benefits of Magnesium?

    Magnesium supports more than 300 enzymatic reactions in the body, making it an essential nutrient for various tissues, organs, and systems. Below are some of the most common reasons that magnesium supplements are used.

    Muscle support

    Magnesium has widely been considered supportive of healthy muscles, but whether it actually improves muscle comfort has not always been clearly shown. A small study of adults with exercise-caused muscle soreness found that 350 mg of magnesium each day helped with muscle soreness when compared to placebo. There’s little other research that explicitly shows benefit for muscle comfort, although balanced magnesium intake is essential for numerous reasons.

    Sleep support

    While magnesium is sometimes found in sleep support formulas, the research on how it affects sleep is mixed. A study that used 226 mg of magnesium at bedtime found that leg cramps and sleep quality were improved after 60 days versus placebo. Other studies have not definitively proven magnesium’s impact on restless legs or other sleep-related issues. Larger studies are needed.

    Heart support

    Research from population studies has found that higher magnesium levels or a reduced incidence of magnesium depletion were linked to better heart health parameters, although more direct clinical trial interventions are needed. Magnesium supplementation has been shown to support healthy metabolic measurements, but larger randomized controlled trials are needed to confirm the impact.

    Bone health support

    Magnesium from dietary and supplement sources support bone mineral health. Population studies have also found that higher consumption of magnesium is also tied to bone strength, Large clinical trials are needed to confirm this.

    Energy support

    There are many small studies that have found magnesium to be supportive of energy metabolism, typically with how carbohydrates are converted and stored or used for energy. However, just as many studies show that the mineral has no effect. Most of these studies are older, and they used different forms of magnesium at different dosages for varying lengths of time, which makes it hard to translate the benefits.

    Population studies link higher intake of magnesium with improved energy metabolism and food for energy use. When people consume less than 250 mg of magnesium per day, there’s a 56% reduction in health potential.

    Digestive health support

    Magnesium has long been used to support bowel regularity. A healthy intake of magnesium that is optimally balanced with calcium has been linked to more medium-chain fatty acids (MCFAs), which can be consumed from foods or synthesized by the microbiome. In this case, the optimized magnesium intake led to enhanced gut microbial activity to produce MCFA. These healthy fatty acids can be used by the body to energize intestinal epithelial cells, maintain a healthy gut mucosal lining, and support healthy immune system responses.

    Frequently Asked Questions

    What is the most effective form of magnesium?

    The most effective form of magnesium depends on the reason you are taking it. For general magnesium nutrition support, magnesium glycinate is well tolerated and tends to cause fewer gastrointestinal effects than other types. Magnesium lactate is absorbed easily in the gut.

    Can you overdose on magnesium?

    Yes, magnesium is a mineral that is stored in the body and excessive intakes can be harmful to human health. No more than 350 mg should be consumed each day from supplements—this is the tolerable upper intake level. Always consult a healthcare provider before taking supplements, especially before consuming them at high doses.

    Can you get magnesium from food?

    Magnesium is found in many foods. Some of the most abundant sources of magnesium foods include legumes (edamame, black beans, peanuts), nuts (almonds, cashews), dark chocolate, whole grains (oatmeal, whole wheat), and fresh vegetables and fruits (avocado, spinach, kale).

    Can you take magnesium supplements every day?

    Yes, magnesium supplements can be taken every day. Work with your healthcare provider to determine the best way to support your magnesium needs. Do not exceed more than the recommended intake, since excessive magnesium can cause side effects. If you get plenty of magnesium from foods, you may not need a supplement every day. But if you have gastrointestinal conditions or other factors, your healthcare provider may recommend a daily magnesium supplement.

    When is the best time to take magnesium?

    Magnesium should be taken with food to support better absorption. It can be taken at any time of the day, but should ideally not be paired with iron or zinc, to support bioavailability.

    The Bottom Line

    Magnesium is a vital mineral that supports energy metabolism, bone health, and much more. While it’s possible to get enough from the foods that you eat, if you have certain conditions or low dietary intake, a magnesium supplement can help to bridge the gap and support nutritional balance.

    Your healthcare provider can determine the best form of magnesium supplementation for you. Follow their recommendations for dosage, and remember, that many types of magnesium may have laxative uses or side effects—so it’s important to follow dosage guidelines closely. When you’re choosing a magnesium supplement, it’s important to consider quality, the form of magnesium, and how much is in each serving.

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    Laurel Ash, ND
    Laurel Ash, ND: Medical Content Reviewer
    Laurel Ash, ND is a board-certified Naturopathic Physician. She holds additional credentials with a master’s in integrative mental health. Dr. Ash graduated from the National University of Natural Medicine in 2019. Dr. Ash practices in Oregon and Washington where ND’s scope of practice includes primary care. Using the best tools of allopathic/conventional medicine with the holistic tenants of naturopathic medicine has created a powerful force of healing for the patients in her practice. Dr. Ash focuses on combining integrative/functional health modalities with evidence-based medicine. She has experience as a medical reviewer in the holistic medicine field and partners with companies and practitioners to produce science-backed content for readers and consumers interested in holistic medicine. She is passionate about blending the strengths of allopathic and integrative medicine to transform the healthcare industry, empowering people with an understanding of all their options on their wellness journey.
    Mia McNew, MS
    Freelance Contributor
    Mia McNew is a nutrition science researcher with bachelor's and master's degrees in nutrition science and biochemistry. She holds additional certifications in clinical nutrition and formerly managed a private nutrition practice focusing on fertility and the management of chronic health and autoimmune disorders. She is currently pursuing a PhD in human nutrition with a research focus on disability, underserved populations, and inequities in popular nutrition therapy approaches. She has extensive experience as a fact-checker, researcher, and critical research analyst and is passionate about science and health communications that provide practical support.