Where We Stand

Pure Encapsulations Magnesium (Glycinate) is our top pick because it’s a well-tolerated form of magnesium, it’s third-party tested, and it has easily adjustable dosing to meet your individual needs. If you prefer a powdered form, try Thorne Magnesium Bisglycinate powder, and for constipation relief, try Pure Encapsulations Magnesium (Citrate).

Who Should Or Shouldn’t Take a Magnesium Supplement?

If you are magnesium deficient or have a health condition that puts you at risk for deficiency, a magnesium supplement may be beneficial. For healthy adults, the body is able to excrete excess magnesium from food; however, over-supplementation of magnesium can lead to negative side effects. Additionally, there are certain populations that may be more susceptible to the adverse effects of excess magnesium supplementation, including people with impaired kidney function, infants and children, and people taking certain medications. People who may benefit from a magnesium supplement include:

• People who do not consume balanced diets: People who have difficulty incorporating magnesium-rich foods like seeds, nuts, spinach, whole grains, yogurt, and legumes into their diets may be at higher risk for deficiency. If adding these foods is not feasible due to dietary restrictions or preferences, a supplement may be beneficial.
• People with gastrointestinal issues: Gastrointestinal diseases such as celiac disease, Crohn’s disease, Ulcerative colitis, and irritable bowel syndrome (IBS), may result in malabsorption that can lead to magnesium depletion, so in some cases, magnesium supplementation may be indicated. Additionally, magnesium citrate specifically may help to prevent and alleviate constipation, a common symptom of certain gastrointestinal diseases. Ella Soderholm, RN, MNT, says she primarily uses magnesium “for the beneficial effects it has on gut health, aiding in peristalsis, helping move food through your intestines and prevent[ing] constipation.”
• People who suffer from migraines: While it is still a new area of research, it has been found that people who suffer from migraine headaches may have a lower level of magnesium in their blood and tissues when compared to those who do not suffer from migraines. The American Academy of Neurology and the American Headache Society now provide evidence-based guidelines stating that magnesium therapy may be effective for migraine prevention under the supervision of a healthcare provider. “Magnesium, in particular magnesium oxide, has also been studied in migraine headaches as an effective preventative nutraceutical,” states Ann Ming Yeh, MD.
• People who are pregnant or breastfeeding: During pregnancy and lactation, a person’s magnesium needs increase to support not only themself, but their growing baby. If a new or pregnant parent is not meeting their magnesium needs from diet and a prenatal vitamin, it may be beneficial to speak to a healthcare provider about adding a magnesium supplement.
• People with diabetes: Becausemagnesium plays an important role in the insulin response system, magnesium deficiency can promote further insulin resistance in those with type 2 diabetes. Additionally, uncontrolled or prolonged elevated blood sugar in insulin-resistant and insulin-dependent diabetics can cause increased urinary output, resulting in increased losses of electrolytes, including magnesium. Some studies have shown that supplementing with magnesium may improve diabetes-related health measures; however, more research is needed. Be sure to speak to a healthcare provider to determine if a supplement may benefit you.
• Older adults: As we get older, there are a couple of scenarios that could lead to magnesium deficiency. One is an overall decrease in total dietary intake. If an older adult is unable to consume a varied diet, their risk of magnesium deficiency is greater. Another is that, as we age, our bodies’ ability to properly and efficiently absorb all nutrients decreases. And third, there are certain medications that may alter magnesium levels, increasing the risk for magnesium deficiency.

How We Select Supplements

Our team works hard to be transparent about why we recommend certain supplements; you can read more about our dietary supplement methodology here.

We support supplements that are evidence-based and rooted in science. We value certain product attributes that we find to be associated with the highest quality products.

It’s important to note that the FDA does not review dietary supplements for safety and effectiveness before they go to market. Our team of experts has created a detailed, science-backed methodology to choose the supplements we recommend.

What to Look For

Third-Party Testing

Supplements that are third-party tested are sent to a lab where they are tested for purity and potency to ensure they contain what they say they contain and do not contain any potential contaminants. Trusted third-party certifications include ConsumerLab.com, NSF, USP, and Informed Choice. However, these certifications can be difficult to obtain and expensive for manufacturers, so many companies choose not to get their products tested. If you are selecting a supplement that does not have third-party testing, we recommend choosing a trusted brand that does rigorous internal testing.

The Types of Magnesium

Shopping for a magnesium supplement can be overwhelming. Not only can a magnesium supplement come in a tablet, capsule, cream, or powder, but that same supplement can come in a variety of different forms. Different magnesium forms include magnesium glycinate, citrate, threonate, malate, and chloride.

The following are all bioavailable forms of magnesium (meaning our body can absorb and utilize them) that differ slightly in absorption rate and function:

• Magnesium glycinate: Typically well tolerated at high doses, magnesium glycinate is a suitable option for treating magnesium deficiencies. The amino acid glycine may enhance the quality of sleep in humans, which may make it a good option for sleep and relaxation. In this form, the magnesium is bound to glycine to form chelated magnesium, which is absorbed better than other forms of magnesium.
• Magnesium citrate: Magnesium citrate pulls water from the body into the gastrointestinal tract, which can increase gut motility, creating a laxative effect. This form may good a good option for alleviating constipation.
• Magnesium L-threonate: Studied for cognitive health due to its ability to cross the blood-brain barrier.
• Magnesium malate: May be the preferred form of magnesium for muscle function, repair, and support.
• Magnesium chloride: A generally well-tolerated, bioavailable option when looking to improve magnesium status.
• Magnesium oxide: May be beneficial in the prevention and management of headaches and migraines.

It is important to choose the best form and dosage based on your specific needs. According to Soderholm, she “uses different types of magnesium depending on my client’s needs. Sometimes I may implement it for stress and its calming effect, while other times I use it for constipation and sluggish bowels.”

Ingredients and Potential Interactions

It is essential to carefully read the ingredient list and nutrition facts panel of a supplement to know which ingredients and how much of each ingredient is included relative to the recommended daily value of that ingredient. Please bring the supplement label to a healthcare provider to review the different ingredients contained in the supplement and any potential interactions between these ingredients and other supplements and medications you aretaking.

There are several medications that can potentially interact with magnesium supplements and, therefore, affect your overall magnesium status. If you are taking any of the below medications, be sure to speak to a healthcare provider about your magnesium intake.

Diuretics: If you are on chronic treatment with diuretics such as Lasix®, Bumex®, Aquazide H®, Edecrin®, or Aldactone®, be sure to speak to a healthcare provider regarding your magnesium status. Certain diuretics can lead to an increased loss of magnesium, while others may cause you to retain magnesium and not excrete it properly.

Proton pump inhibitors (PPI): The Food and Drug Administration (FDA) advises healthcare providers to measure the serum magnesium level in any patient on long-term PPI treatment as PPIs have been known to cause low levels of serum magnesium.

Antibiotics: Magnesium has the potential to bind to certain antibiotics, making them work less effectively. If taking antibiotics such as Declomycin®, Cipro®, Levaquin®, or Vibramycin®, it is advised to take the antibiotic at least two hours before or four to six hours after a supplement containing magnesium.

Bisphosphonates to treat osteoporosis: When taking oral bisphosphonates to treat osteoporosis, it is important to separate that dose from any magnesium-containing supplements by at least two hours as the magnesium has the potential to reduce total absorption of the medication.

How Much To Take

The current Recommended Daily Allowances (RDA) for magnesium from both food and supplements for adults are below listed by age and gender.

• 19-30 years: 400 milligrams (males), 310 milligrams (females), 350 milligrams (pregnancy), 310 milligrams (lactation)
• 31-50 years: 420 milligrams (males), 320 milligrams (females), 360 milligrams (pregnancy), 320 milligrams (lactation)
• 51+ years: 420 milligrams (males), 320 milligrams (females)

In addition to an AI or RDA, as outlined above, the FNB also establishes a Tolerable Upper Intake Level (UL) for various vitamins and nutrients. Exceeding the UL of magnesium from supplements can result in gastrointestinal distress, such as diarrhea, nausea, and cramping. Other symptoms of magnesium toxicity can include low blood pressure, vomiting, muscle weakness, irregular heartbeat, and cardiac arrest.

It is important to note that the ULs are only referring to magnesium ingested in the form of a supplement or medication and not from food, which can be effectively processed and excreted by the kidneys. It is high doses from supplements that can lead to negative side effects. The following are the established Tolerable Upper Intake Levels for magnesium supplements only (not magnesium from food) based on age for both males and females:

• Birth to 12 months: None established
• 1-3 years: 65 milligrams
• 4-8 years: 110 milligrams
• 9-18 years: 350 milligrams
• 19+ years: 350 milligrams

Our Experts

• Ella Soderholm, RN, MNT is a Registered Nurse (RN), Master Nutrition Therapist (MNT), gut microbiome and digestive health expert, and founder of Undercurrent Wellness, LLC.
• Ann Ming Yeh, MD is a Stanford trained pediatric gastroenterologist and integrative pediatrician with over 12 years of experience for taking care of children and optimizing digestive health and wellness.
• Anne Cook Carroll, MS, RD, CDN is a is a Registered Dietitian who works with patients to meet their health goals, and educates patients on the appropriate usage of supplements to optimize their nutritional status and overall health. She also specializes in supplement research and analysis.

Why Trust Verywell Fit

Brittany Scanniello RDN runs an integrative nutrition practice in Lafayette Colorado, Eat Simply Nutrition. She is constantly looking for nutraceutical alternatives to assist day-to-day concerns of her clients. With a background as a clinical pediatric gastrointestinal dietitian, magnesium was a supplement she worked with often and continues to do so. She emphasizes the importance of purity, safe dosages, and a quality product above all else when recommending any form of supplementation.