Magnesium L-Threonate vs. Magnesium Glycinate

Magnesium is an essential mineral that supports more than 300 chemical reactions in our body, including: [1]

Energy production and storage
Protein synthesis
DNA and mitochondrial health
Cardiovascular health
Nerve and muscle function
Bone health
Stress reduction
Glucose and insulin metabolism

It’s evident that magnesium plays a significant role in overall health. We're consuming less magnesium through food such as leafy greens, legumes, nuts, and seeds than we once did. In the 1900s, the average adult consumed ~500 mg per day, but that has lowered to the current average intake of ~175 mg per day (Recommended Dietary Allowance (RDA) for magnesium is ~320-420 mg per day for adults). If your body is low in magnesium, you may experience nausea, headaches or migraines, constipation, muscle cramps, numbness or tingling, irregular heartbeat, fatigue, and general weakness. Low levels can also contribute to chronic disease such as type 2 diabetes, heart disease, Alzheimer’s disease, and osteoporosis [1].

Common Types of Magnesium

While we always emphasize a food first to restore micronutrients, many of us find supplementing magnesium to be helpful based on our unique health needs and goals. But how do you choose when there are 10 different types out there? We’ll focus on three of the most commonly recommended types of magnesium and their benefits to help you choose the right fit and/or combination for your needs.

Magnesium L-Threonate
Magnesium Glycinate
Magnesium Citrate

Magnesium L-Threonate vs Magnesium Glycinate

Magnesium l-threonate and magnesium glycinate are both noted for having calming effects and supporting sleep [2, 3]. However, they both offer unique benefits too.

Magnesium l-threonate is magnesium bound to L-threonic acid (water soluble metabolite of vitamin C), which is naturally found in our body in areas like cerebrospinal fluid and blood plasma.

This provides a unique opportunity for it to cross the blood brain barrier and support brain health [4]. Studies have found magnesium l-threonate to support sleep, memory, learning, mood, and potential to protect against age-related cognitive decline [2, 5]. A 2015 randomized, double-blind, placebo-controlled study found cognitive improvement in subjects aged 50-70 years old with cognitive impairment. Subjects took 108-144 mg per day of elemental magnesium l-threonate (dosage based on weight) for 12 weeks. They saw significant improvements over the placebo group in three of four cognitive domains (executive function, working memory, and episodic memory) and a significant reduction in cognitive fluctuations [6].

Another randomized, double-blind, placebo-controlled study in 2024, looked at the effects of magnesium l-threonate on sleep quality in subjects aged 35-55 years old who self-reported poor sleep quality. Participants took 75 mg per day of elemental magnesium l-threonate for 21 days and sleep quality was objectively and subjectively evaluated based on Oura ring data and sleep questionnaires. The Oura ring showed significant improvements in the magnesium l-threonate group versus the placebo group in deep sleep, REM sleep, light sleep, activity and readiness parameters, and readiness sleep balance. Additionally, subjective sleep questionnaires showed significant improvement in the magnesium l-threonate group versus the placebo group in behavior upon waking, energy and daytime productivity, grouchiness, mood, and mental alertness [2].

While magnesium l-threonate supports cognitive health, magnesium glycinate has positive relaxing and calming effects.

Magnesium glycinate is bound to the amino acid glycine (acts as a neurotransmitter with calming properties), which allows it to be gentle on the stomach, highly absorbable, and calming for both the body and mind.

This makes it a great choice for improving sleep quality, promoting relaxation, and regulating stress and mild anxiety, which are also helpful for supporting brain health [5]. In 2025, researchers conducted a randomized, double-blind, placebo-controlled study of subjects aged 18-65 years old with poor self-reported sleep quality. Participants took 250 mg of elemental magnesium glycinate per day for four weeks. Subjects who took the magnesium glycinate saw significant improvements in their Insomnia Severity Index (ISI) score compared to subjects on the placebo [3].

Magnesium Citrate vs Magnesium L-Threonate and Magnesium Glycinate

Magnesium citrate offers different benefits from the cognitive support of magnesium l-threonate and the calming effects of magnesium glycinate.

Magnesium citrate is bound to citric acid to form magnesium citrate, which is a very soluble form of magnesium that draws water in and provides a laxative effect [7].

This is great for anyone who has constipation and/or wants to soften their stools.

Best Type of Magnesium for You

While all three of these magnesium types offer positive benefits, the one or ones you choose are based on your health needs and goals. Here is a summary of their benefits:

Magnesium L-Threonate: choose this if you're looking to support cognitive health and sleep.
Magnesium Glycinate: choose this if you’re looking to support improving sleep quality, promote relaxation, and regulate stress and mild anxiety.
Magnesium Citrate: choose this if you’re navigating constipation and would like to support regular bowel movements.

Magnesium Glycinate

Our favorite calming mineral that helps with over 300 functions in the body.

$34.00

Calming Magnesium Powder

Support focus, memory, and calm—naturally.

$59.00

Often, you may find that you benefit from a combination of magnesium forms. For example, if you would like to support overall brain health and improve bowel regularity, then you could take a combination of both magnesium l-threonate and magnesium citrate. However, if your goal is to improve memory and provide relaxation, then you may want to start with magnesium l-threonate, such as our Calming Magnesium Powder. This magnesium supplement includes magnesium l-threonate to naturally support focus, memory, and calm. You can mix 1 scoop with water, a beverage of your choice like sparkling water as a mocktail, or with electrolytes for a full mind-body support drink.

No matter what supplement you are looking at, it’s helpful to speak with a doctor or dietitian on which magnesium form(s) best aligns with your health needs and goals as well as determining a starting dosage and supplement timing.

Schedule a virtual visit with a Root doctor or dietitian.

References:

Bring Root to your Company

Root delivers clinically validated functional medicine for top-performing teams. Transform your team’s health and your company’s health spend today.

Learn More