Which Magnesium Is Best for Sleep? What Is Magnesium?

Magnesium is a mineral that is essential for human health, and one of the most abundant electrolytes in the human body. Like all essential nutrients, magnesium cannot be produced by the body and so it must be obtained from food or supplementation.

Once obtained from the diet, magnesium is involved in more than 300 enzyme systems and biochemical reactions in the human body, including:¹

• Protein synthesis
• Muscle and nerve function
• Blood glucose control
• Blood pressure regulation

Magnesium Is a Nutrient Gap for 49% of Americans

Despite its important role in the body, national intake data shows that 49% of Americans have a magnesium nutrient gap, meaning they consume less than the recommended amount of magnesium each day.² This could be due to changes in eating patterns, like increased consumption of processed foods, and even changes in magnesium content in the soil used to grow our food (Cazzola, 2020). Regardless, magnesium plays a key role in neurotransmitter and hormone function to support sleep, and this lack of magnesium intake from our everyday diet could contribute to the growing number of people reporting sleep issues.

Curious about how much magnesium you should consume daily? The recommended daily amount varies by sex, age, and other factors. However, most adults require 310–420 mg per day.3 When looking to make food choices that are good sources of magnesium, look for the following:

• Spinach and other leafy greens
• Avocados
• Nuts and seeds (pumpkin seeds, almonds)
• Beans and legumes

Why Are There So Many Types of Magnesium Supplements?

If you’re one of the almost 60% of Americans who regularly take a nutrition supplement, you may have looked into taking a magnesium supplement and discovered that there are many different types of magnesium available (CDC). Magnesium L-threonate, magnesium glycinate, magnesium citrate, magnesium malate, and magnesium oxide are just some of the supplement options available.

Magnesium supplements are named based on the substance attached to it that helps your body to absorb magnesium. These different substances may result in different absorption rates, and different gastrointestinal side effects. For example, magnesium citrate is a combination of magnesium ions and citrate, and when combined, form the salt known as “magnesium citrate.”

As a part of AGZ, we utilize a blend of two science-backed magnesium sources, magnesium L-threonate, or Magtein®, and magnesium bisglycinate. Magtein® in particular is a bioavailable source of magnesium with research backing to show that it may support sleep quality (Hausenblas 2024).

Types of Magnesium for Sleep

If you are trying to determine which magnesium is best for sleep, here are five of the most common types of magnesium to choose from:

Magnesium L-Threonate (Magtein®)

• Why people use it: Magtein® magnesium L-threonate is a clinically studied form of magnesium that has been shown to improve sleep quality and support cognitive function (Hausenblas 2024).
• Key feature: This unique property makes it appealing for supporting brain health and relaxation. AG1’s AGZ includes Magtein® magnesium L-threonate, chosen for its high bioavailability and research-backed profile.4

Magnesium Glycinate

• Why people use it: It can have calming effects and is popular as a magnesium supplement for sleep.
• Key feature: It’s paired with glycine, an amino acid that may support relaxation that’s gentle on digestion.

Magnesium Citrate

• Why people use it: Highly absorbable and commonly taken to support digestive regularity.
• Key feature: At higher doses, it can have a mild laxative effect, making it potentially better suited for daytime use.

Magnesium Malate

• Why people use it: Supports energy production and muscle recovery.
• Key feature: Some find it slightly energizing, making it a preferred choice for use earlier in the day.

Magnesium Oxide

• Why people use it: Provides a high amount of elemental magnesium.

Key feature: Less easily absorbed and more likely to cause digestive discomfort compared to other forms.

Benefits of Magnesium for Sleep

Magnesium plays a crucial role in helping the body transition into rest. Research suggests that higher levels of magnesium are linked with better sleep quality, longer sleep duration, and reduced daytime fatigue.5

While there is much to learn about all the ways that magnesium can impact sleep, evidence shows magnesium may influence a few key processes that impact how relaxed or tired you may feel, including:6

• Neurotransmitter function. Magnesium helps to synthesize and facilitate the function of GABA, or Gamma-Aminobutyric Acid, which is a calming neurotransmitter that signals to your central nervous system that it’s time for sleep.
• Melatonin production. Magnesium plays a role in producing natural melatonin concentrations which can help lead to feelings of sleepiness (Held et al., 2002).
• Cortisol suppression. While producing melatonin, magnesium helps to reduce the amount of cortisol in our body, signaling to the body that it’s time to sleep.

Put all of these functions together, and it’s no wonder magnesium is one of the most popular and science-backed tools for supporting sleep.

Should You Take a Magnesium Supplement?

If you’re not getting enough magnesium in your diet or want more targeted support, a magnesium supplement for sleep or other reasons may be a worthwhile option to explore.

Here are a few things to keep in mind:

• Address your diet first. Aim to increase your magnesium from foods first, then look toward supplementation.
• Match the form to your needs. For example, magnesium L-threonate may be best for supporting sleep quality.
• Start small. Begin with a modest dose closer to what may be found in food items and see how your body responds.

The Takeaway

So, which magnesium is best for sleep? While no single form works for everyone, magnesium L-threonate and magnesium bisglycinate are among the most recommended for relaxation and nighttime use. Combining magnesium-rich foods with the right supplement can help your body stay balanced and better prepared for restorative rest.

References

1. National Institutes of Health, Office of Dietary Supplements. Magnesium — Health Professional Fact Sheet. NIH ODS. https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/ Office of Dietary Supplements
2. U.S. Department of Agriculture, Agricultural Research Service. Usual Nutrient Intake from Food and Beverages, by Gender and Age: What We Eat in America, NHANES 2017–March 2020 Prepandemic – Usual Intakes of Males and Females. USDA ARS; 2023. https://www.ars.usda.gov/ARSUserFiles/80400530/pdf/usual/Usual_Intake_MaleFemale_WWEIA_2017_March%202020.pdf ARS
3. Sleep Foundation. Using Magnesium for Better Sleep. Sleep Foundation. https://www.sleepfoundation.org/magnesium Sleep Foundation
4. Threotech LLC. Magtein — Magnesium L-Threonate. https://magtein.com/