Is Magnesium Glycinate Or Magnesium Citrate Better For Sleep?

Sleep can be hard to come by sometimes. Stress, a heavy dinner, or that second martini too close to bedtime can all mess with your chances of getting a solid seven hours. Maybe you've already tried melatonin to get on a more consistent sleep schedule. Maybe meditation or light stretching helps you wind down, but your nerves still feel like they need a little extra help.

That's where magnesium might come in. A magnesium supplement can help relax your muscles and calm your nervous system. But with so many different types out there, it's hard to know which one to choose. Some magnesium supplements can get things moving in your gut (sometimes a little too much), while others are better suited for promoting rest. Magnesium glycinate and magnesium citrate are two common magnesium supplements. Both are available in powder form, so you can mix them into water or a trendy Sleepy Girl Mocktail. But if sleep is your goal, magnesium glycinate might be the better bet.

While magnesium citrate and other forms can support sleep, it also has a laxative effect, according to Harvard Medical School. In other words, magnesium citrate might have you racing to the bathroom in the morning, or even in the middle of the night. Magnesium glycinate is generally easier on the stomach and may also help ease anxiety, making it a solid choice for better sleep.

Magnesium and the amino acid glycine combine to form magnesium glycinate. Magnesium itself isn't specifically designed as a sleep aid, but it helps balance muscle and nerve function, which may help your body relax. You also need magnesium to produce serotonin to regulate your mood. Glycine is a non-essential amino acid that acts as an antioxidant and may have a calming effect on the brain. Even though magnesium glycinate supplements are often marketed for sleep, the research on their direct effect on sleep is still limited.

A 2025 study in Sleep tested a sleep supplement containing magnesium glycinate on peri- and postmenopausal women with sleep problems. After three weeks, the women taking the supplement slept about 41 minutes longer than those on a placebo. They also experienced fewer sleep disturbances, better sleep quality, and greater satisfaction with their sleep. However, it's hard to tell whether magnesium glycinate alone or the other ingredients in the supplement were responsible for the improvements.

When it comes to magnesium glycinate and sleep, it might actually be the glycine doing most of the work. A 2012 review in the Journal of Pharmacological Sciences suggests glycine may improve sleep in several ways. Glycine crosses the blood-brain barrier and slows brain activity. It also helps open blood vessels and lower body temperature. Because people tend to sleep better when their core body temperature drops, this may explain some of glycine's benefits.

Your body stores about 25 grams of magnesium, mostly in your bones and soft tissues. Adult men need at least 420 milligrams of magnesium each day, and women should aim for 320 milligrams. Pregnant and breastfeeding women need a little more magnesium. You can get more magnesium from food without the laxative side effects, but most people don't get enough magnesium in their diets. What's challenging is that your body can only absorb between 30% and 40% of the magnesium in your diet.

Another challenge is that some of the food you eat can make it hard to keep magnesium in your body. Processed foods that are high in sugar or sodium can cause your body to shed magnesium through your urine. Oxalates found in spinach, nuts, and beet greens can bind with magnesium and limit magnesium's absorption.

Some popular magnesium forms aren't even absorbed well by your body, according to a 2019 study in Biological Trace Element Research. Magnesium malate is absorbed well and stays in your blood the longest, while magnesium acetyl taurate is quickly absorbed and improves magnesium levels in your brain. Magnesium citrate and magnesium oxide had the lowest absorption and had less of an effect on the body. Magnesium glycinate wasn't tested in this study.