The 7 best magnesium supplements of 2026, tested and reviewed by a dietitian

Constipated? Trouble sleeping? Legs cramping? Magnesium might help. Roughly two-thirds of U.S. adults may have low magnesium levels, according to a recent analysis of national health survey data — even though it’s found in everything from leafy greens to nuts and whole grains. If your diet falls short, a supplement may help fill the gap. According to Dr. Raj Dasgupta, chief medical adviser for Garage Gym Reviews, magnesium can “support stress reduction, better sleep and even digestive health” — making it a go-to for a range of common concerns.

The catch? Not all magnesium supplements are created equal. Different forms serve different purposes: Magnesium glycinate is often recommended for stress and sleep, while magnesium oxide is more commonly used for heartburn or indigestion. Plus, not all supplements are tested to verify the contents match what’s listed on the label.

As a registered dietitian and senior wellness writer, I’ve tested countless multivitamins and supplements and take magnesium daily to help with IBS symptoms. To determine the best magnesium supplements, I drew on my personal experience and nutrition expertise to evaluate more than 25 options on formulation, ingredient quality, third-party testing, availability and price. After narrowing the field to 16 standouts, I worked with a panel of testers to assess them firsthand. Here are the seven that rose to the top.

Best overall magnesium supplement

More top magnesium supplement picks for 2026

How much magnesium do you need?

The recommended daily allowance (RDA) for magnesium varies by age and sex. Here’s how much magnesium to aim for throughout the day:

Magnesium supplements can help make up the difference between what you get from food and what you need to meet daily magnesium targets. For most healthy adults, supplements providing up to 100% of the Daily Value (DV) are sufficient. However, if you have a confirmed magnesium deficiency, your health care provider may recommend a higher dose for a limited time to restore normal levels.

Signs of magnesium deficiency

So how do you know if you’re falling short? Below are some signs that may indicate a magnesium deficiency. If you’re concerned, consider making an appointment with your doctor, who can order blood work to check your levels and help determine next steps.

Early signs of magnesium deficiency:

Signs of severe deficiency:

• Numbness or tingling sensations

• Abnormal heart rhythms (arrhythmias)

Types of magnesium supplements

Magnesium comes in various forms, each offering unique benefits and drawbacks. Choosing the right one depends on your health goals and absorption rate.

Here’s a quick rundown of five of the most common types of magnesium you’ll find in supplements:

• Magnesium glycinate: This form of magnesium combines magnesium and the amino acid glycine. It is easily absorbed and associated with fewer GI side effects than other types. While more research is needed, magnesium glycinate is thought to have calming properties and may help manage stress, anxiety, depression and insomnia.

• Magnesium citrate: This highly absorbable form of magnesium comprises magnesium bound to citric acid, a natural compound found in citrus fruits. This combination enhances solubility and bioavailability, making it one of the most common forms of magnesium supplements used for deficiencies. It also has a mild laxative effect, which makes it an option for relieving occasional constipation. At higher doses, it is often used as a short-term treatment for acute constipation, such as before medical procedures like colonoscopies.

• Magnesium oxide: A salt of magnesium that combines magnesium and oxygen, typically found in powder form. It may help reduce heartburn, stomach upset and chronic constipation. However, because it’s less readily absorbed, it isn’t the best option for increasing blood magnesium levels.

• Magnesium L-threonate: An absorbable form of magnesium created by combining magnesium with threonic acid, a compound derived from vitamin C. While research is ongoing, this form is believed to be especially beneficial for brain health. Studies suggest it may play a role in supporting cognitive function, improving memory and potentially aiding in the treatment of depression and age-related cognitive decline.

• Magnesium malate: A combination of magnesium and malic acid naturally found in fruits. Because it’s readily absorbed and less likely to cause diarrhea, it’s sometimes recommended instead of magnesium citrate to treat magnesium deficiencies.

Factors to consider when shopping for magnesium supplements

With so many magnesium supplements on the market, choosing the right one for your specific health goals can be difficult. Here’s what to keep in mind to select the best magnesium supplements for you:

• Type of magnesium: Different forms of magnesium serve different purposes. Magnesium glycinate is often used for sleep and anxiety, while magnesium oxide is more effective for relieving constipation. Choosing the right type depends on your specific health needs.

• Form: Magnesium supplements are available in capsule, liquid, powder and gummy form. While liquid supplements generally absorb faster, choose a form you feel comfortable taking regularly.

• Bioavailability and absorption rate: Some types of magnesium are more readily absorbed than others. If you have a confirmed magnesium deficiency, select a form that’s easier for your body to absorb, like magnesium glycinate.

• Dosage per serving: The ideal amount of magnesium per serving depends on the type of magnesium, the intended benefit and how much magnesium you’re already getting in your diet. A doctor or registered dietitian can help identify the correct dose for you.

• Additional ingredients and fillers: Whenever possible, choose a supplement with minimal additives, such as artificial colors or fillers. Some products also include extra nutrients, which may be beneficial depending on your diet, but if you’re already getting these from other supplements, they may not be necessary.

• Third-party testing: It’s essential to select supplements tested for purity and potency, ideally by a third-party organization such as NSF, UL Solutions or US Pharmacopeia (USP).

• Potential side effects: Certain forms of magnesium are more likely to cause side effects than others. Magnesium oxide, for example, is known to cause diarrhea, whereas magnesium glycinate is generally well-tolerated. Research each form of magnesium to understand its potential side effects.

• Value: Good-quality magnesium supplements are available at virtually every price point. Because some products require taking multiple pills or gummies daily, comparing the price per serving is important when deciding which product is best for your budget.

How we test magnesium supplements

As a registered dietitian with nearly a decade of experience, I’ve closely followed the latest in dietary supplements to ensure the most up-to-date recommendations. To provide a well-rounded perspective, I consulted a fellow registered dietitian and a board-certified physician for their insights on magnesium supplements and the various available forms.

During our first round of testing, our team reviewed more than 20 products from over 15 brands, narrowing the field to 11 magnesium supplements. More recently, we reviewed five additional products and tested three powders. With the help of family and friends, each product was tested for at least one week.

Here’s what we considered when choosing our top picks:

Other magnesium supplements we tested

We’re always on the lookout for magnesium supplements worth testing to see whether they bring something new to the category. While we’ve tried many strong options over the past two years, not all made the cut as our “best” picks. That doesn’t mean they’re not worth considering. Here are seven additional magnesium supplements we tested, along with a brief overview of their pros and cons:

• Quince Magnesium Glycinate Plus: I considered naming this our pick for the best magnesium supplement for sleep. Thorne’s magnesium biglycinate ultimately held onto the top spot thanks to the brand’s strong reputation for high-quality, rigorously tested supplements and its magnesium-only formula. That said, if you’re comfortable with the addition of L-theanine — an amino acid known for its sleep-promoting effects — and a subtle berry flavor, this powder from Quince is well worth considering. Read our full Quince supplements review.

• Lunakai Magnesium Glycinate + L-Theanine: These fruit-flavored gummies are our top pick if you’re looking for a magnesium supplement to support sleep. They’re third-party tested and include L-theanine for an added calming effect. My mom has tried countless sleep supplements, and these are by far her favorite. However, I found them too sweet for my taste.

• Nordic Naturals Kids Calm Gummies: Formulated for children ages 3 and up, each two-gummy serving provides 200 mg of magnesium citrate and 50 mg of L-theanine for a gentle calming effect. My 5-year-old enjoys the watermelon flavor, and I’ve been pleasantly surprised to find that they help him wind down at night. Just be sure to check with your child’s pediatrician before trying them.

• Ora Magnificent 4-in-1 Powder: This third-party tested, vegan-friendly powder combines four readily absorbed forms of magnesium — glycinate, citrate, malate and taurate — to deliver a broad range of benefits. While it’s worth trying if you prefer a powdered supplement, our tester wasn’t a huge fan of the taste: it has a very strong tangerine flavor, reminiscent of Tang, with a lingering aftertaste.

• HUA Whole Food Magnesium Powder: This marine-based magnesium powder is made with magnesium sourced from seawater and red algae near Ireland and Iceland. It’s free of artificial additives and available in two stevia-sweetened flavors. While our tester preferred the taste to Ora’s powder, there was still a noticeable stevia aftertaste. It’s also worth noting that marine-sourced magnesium isn’t as widely studied as some other forms. That aside, we were impressed by the whole-food formulation and third-party testing for purity and potency.

• MegaFood Magnesium 300 mg Capsules: These vegetarian-friendly capsules contain three easily absorbed forms of magnesium: citrate, malate and glycinate. While we liked that the supplement is designed to be gentle on the stomach and can be taken at any time of day, the capsule’s large size and rough texture made it harder to swallow.

• Trace Minerals Mega-Mag Liquid Magnesium Chloride: This liquid option is hard to beat. It’s formulated for optimal absorption and third-party tested to ensure purity and potency. The tricky part is the recommended dose of 20 drops per day. While you can spread the dose throughout the day, we struggled to remember to do so.

• Trace Minerals No Muscle Cramps: This liquid supplement contains a unique blend of magnesium and electrolytes to keep muscle cramps at bay. While it has hundreds of rave reviews online, our tester found it hard to get past the oily texture when mixed with water.

• Nature Made Magnesium Glycinate: Easily available in stores and online, this option is formulated to be readily absorbed and gentle on the stomach. The biggest downside is the recommended dose of three relatively large capsules daily. Plus, unlike many Nature Made supplements, this one isn’t third-party certified

FAQs

Why is magnesium important?

Magnesium is responsible for over 300 enzymatic reactions in the body. “It is essential for muscle, nerve and heart function, as well as energy production,” says Best, adding, “Magnesium deficiencies can lead to serious health and quality of life issues, including anxiety, poor sleep, muscle spasms, poor bone health and migraines, to name just a few.”

What are the benefits of taking magnesium supplements?

Magnesium supplements are a convenient way to ensure you get enough of this essential mineral in your diet. Depending on the form you take, magnesium supplements can also help prevent migraines, ease constipation, improve sleep and lower stress and anxiety levels.

Are there side effects of taking magnesium?

“Taking too much magnesium can cause diarrhea, nausea or stomach cramps. It can also interact with certain medications, so talk to your doctor first,” notes Dasgupta.

Does magnesium lower blood pressure?

Studies show that magnesium can help lower blood pressure in people who have conditions like untreated or uncontrolled high blood pressure, heart disease or type 2 diabetes. That said, if your blood pressure is already in a healthy range, you probably won’t see much of an additional benefit from taking magnesium supplements.

When is the best time to take magnesium supplements?

The best time to take a magnesium supplement depends on why you’re taking it — and when you’re most likely to remember. After all, consistency matters most. That said, because magnesium can have a calming effect, it’s often best to take it about 30 minutes before bedtime if you’re using it to support sleep. For general health or other benefits, such as helping with chronic constipation, taking it in the morning may be more convenient. And if you’re using a form of magnesium that’s more likely to have a laxative effect, taking it earlier in the day can help reduce the chance of middle-of-the-night bathroom trips.

Which type of magnesium is best absorbed?

According to Dasgupta, “Magnesium glycinate and magnesium L-threonate are among the most bioavailable forms, meaning your body can absorb and use them efficiently.” Magnesium citrate is also easily absorbed, though it “has a laxative effect that some may want to avoid,” adds Best.

Can magnesium supplements help with sleep?

“Yes, magnesium can help with sleep because it supports muscle relaxation, calms the nervous system and might lower cortisol levels. It also plays a role in melatonin production, which can help regulate your circadian rhythm. However, its impact isn’t guaranteed, so it’s best to manage expectations,” explains Dasgupta.

What are the best sources of magnesium? 

The best sources of magnesium are typically plant-based foods that are high in fiber, such as nuts, seeds, leafy greens, potatoes, beans and legumes. That said, magnesium can also be found in a variety of animal foods, including salmon, halibut, chicken and beef. 

Meet our experts

• Trista Best, MPH, RDN, LD, registered dietitian at the Candida Diet

• Raj Dasgupta, quadruple board-certified physician, chief medical advisor for Garage Gym Reviews 

Update, October 1, 2026: We checked all product prices and availability. Our No. 1 pick for best overall magnesium supplement is unchanged.

A note on supplements: The products included on this list are dietary supplements. Statements about these products have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. Dietary supplements are not appropriate for everyone and may interact with other supplements or medications, so talk to your healthcare provider before adding a dietary supplement to your routine.

Our health content is for informational purposes only and is not intended as professional medical advice. Consult a medical professional on questions about your health.