Sometimes, achieving restful sleep can be quite challenging. Factors like stress, a heavy meal, or consuming that second martini too close to bedtime can all interfere with your ability to get a solid seven hours of sleep. Perhaps you’ve tried melatonin to establish a more consistent sleep routine. While meditation or light stretching might help you unwind, your nerves may still feel like they need some extra support.
This is where magnesium might be beneficial. A magnesium supplement can assist in relaxing your muscles and calming your nervous system. However, with various types available, it can be difficult to choose the right one. Some magnesium supplements can stimulate your digestive system (sometimes excessively), while others are more suitable for promoting relaxation. Magnesium glycinate and magnesium citrate are two widely used magnesium supplements. Both are available in powder form, allowing you to mix them into water or a trendy Sleepy Girl Mocktail. But if your main goal is sleep, magnesium glycinate might be a more suitable choice.
While magnesium citrate and other forms can aid sleep, it also has a laxative effect, according to Harvard Medical School. In other words, magnesium citrate might lead to frequent bathroom trips in the morning or even during the night. On the other hand, magnesium glycinate is generally gentler on the stomach and may also help reduce anxiety, making it a reliable option for improving sleep quality.
How magnesium glycinate may affect sleep
Magnesium glycinate is a compound of magnesium and the amino acid glycine. While magnesium itself isn’t specifically formulated as a sleep aid, it helps balance muscle and nerve function, which can promote relaxation. Additionally, magnesium is essential for serotonin production, which regulates mood. Glycine, a non-essential amino acid, acts as an antioxidant and may have a calming effect on the brain. Although magnesium glycinate supplements are often marketed for sleep, research on their direct impact on sleep remains limited.
In a 2025 study published in Sleep, a sleep supplement containing magnesium glycinate was tested on peri- and postmenopausal women with sleep issues. After three weeks, participants taking the supplement slept approximately 41 minutes longer than those on a placebo. They also experienced fewer sleep disturbances, improved sleep quality, and greater overall satisfaction with their sleep. However, it’s unclear if magnesium glycinate alone or other ingredients in the supplement were responsible for the improvements.
Regarding magnesium glycinate and sleep, it might actually be the glycine contributing most to the effects. A 2012 review in the Journal of Pharmacological Sciences suggests that glycine may enhance sleep in various ways. Glycine can cross the blood-brain barrier and reduce brain activity. It also aids in opening blood vessels and lowering body temperature. Since people tend to sleep better when their core body temperature drops, this might explain some of glycine’s benefits.
Your body doesn’t absorb magnesium well
Your body stores around 25 grams of magnesium, primarily in your bones and soft tissues. Adult men require at least 420 milligrams of magnesium daily, while women should aim for 320 milligrams. Pregnant and breastfeeding women need slightly more magnesium. Although you can increase your magnesium intake from food without experiencing laxative side effects, most people don’t consume enough magnesium in their diets. A challenge is that your body can only absorb between 30% and 40% of dietary magnesium.
Another issue is that certain foods can hinder magnesium retention in your body. Processed foods high in sugar or sodium can cause your body to expel magnesium through urine. Oxalates present in spinach, nuts, and beet greens can bind with magnesium, limiting its absorption.
Some popular forms of magnesium aren’t absorbed well by your body, according to a 2019 study in Biological Trace Element Research. Magnesium malate is efficiently absorbed and remains in your blood the longest, while magnesium acetyl taurate is quickly absorbed and enhances magnesium levels in your brain. Magnesium citrate and magnesium oxide had the lowest absorption rates and exerted less of an effect on the body. Magnesium glycinate wasn’t included in this study.
