The Best Time to Take Magnesium Supplements for Optimal Health

Magnesium is needed for various body functions, including producing energy, bone health, and muscle and nerve health. The best time to take a magnesium supplement depends on several factors, including the type of magnesium it contains and the condition it is being used to treat.

The recommended daily magnesium intake ranges from 400-420 milligrams in adult men and 310-320 milligrams in adult women. In people who are pregnant, the recommended daily intake is 350-360 milligrams.

Most people can get magnesium through their diet, but a magnesium supplement may be helpful for conditions like sleep, anxiety, and constipation.

With a few exceptions, the time of day you take a magnesium supplement does not typically affect how well it works or the potential for side effects. To get the health benefits of magnesium, you have to take it consistently.

Once you start taking magnesium, sticking to a consistent dosing schedule helps ensure you don’t miss any doses. To avoid missing a dose, try using a pill box, setting alarm reminders, and using a calendar or list to check off when you take each dose.

Types of Magnesium

When determining the best time to take a magnesium supplement, there are two main factors to consider, which are the type of magnesium and the health concern being addressed. Examples of common types of magnesium and their uses include:

Magnesium oxide: Magnesium oxide is commonly used to help with heartburn, migraines, constipation, and low magnesium levels. However, it’s not as easily absorbed or broken down by your body. It can cause gastrointestinal (stomach and intestine) side effects like diarrhea.
Magnesium citrate: Magnesium citrate is mainly used to treat constipation and help clear the bowels. It’s absorbed by the body better than other magnesium types and often causes fewer side effects.
Magnesium glycinate: Magnesium glycinate is commonly used to treat symptoms of anxiety and depression and improve sleep. It is absorbed well by the body and does not cause many gastrointestinal side effects.
Magnesium taurate: Magnesium taurate has been studied for heart, anxiety, and brain health. Studies have found that it is rapidly absorbed in the body and can quickly reach the brain.
Magnesium sulfate: Magnesium sulfate is often used to treat constipation, increase magnesium levels, and prevent seizures in people with preeclampsia (high blood pressure during pregnancy) through an IV administration. The body doesn’t absorb it as well as other forms, so it can cause gastrointestinal side effects like diarrhea.
Magnesium threonate: Magnesium threonoate has been studied in brain health and pain relief.

If you are interested in taking magnesium, talk with a healthcare provider. They can help you determine which type of magnesium is best for your health concerns and conditions.

It may be best to take magnesium supplements in the morning if you are using them for anxiety, brain health, migraines, or constipation.

For Anxiety

The magnesium types often used for anxiety (glycinate, taurate, threonate) are absorbed quickly in the stomach. Taking the supplement early in the day may give you the most mental support to make it through the day.

If the morning does not work for your schedule, taking the supplement at night is also safe.

For Migraines

If you’re using magnesium to help treat or prevent migraines, taking the supplement during the day may provide the most protection while awake and active.

Taking it at night is also fine. Consistency is most important with medications to prevent migraines, so taking magnesium every day at a consistent time will provide the most benefit.

For Constipation

If you’re treating constipation, taking magnesium during the day may be safest. The time it takes for magnesium to affect your bowel movements varies. For example, magnesium citrate usually causes a bowel movement anywhere from 30 minutes to six hours after you take a dose.

Taking magnesium before bed may cause you to wake up in the middle of the night to use the bathroom. However, some argue that taking magnesium at night allows the medication to work while you rest. Either way, it’s safe to take it at whichever time of day is best for you.

It is best to take magnesium supplements at night if you are using them for sleep or to calm your mood. Researchers believe magnesium may play a small role in the natural creation of melatonin, a hormone that helps regulate your sleep cycle. Studies have found that magnesium helps improve sleep quality and how long you stay asleep, specifically in people without any depression-related disorders.

Low magnesium levels are associated with poor sleep quality. It is important to ensure that your magnesium levels are consistently normal or above normal to improve your sleep quality.

Magnesium can be taken with or without food.

Some studies have warned that foods high in fiber may cause issues with magnesium absorption. Fiber takes up space in the stomach and intestines, blocking magnesium from being absorbed where it usually would. More research is needed to understand this interaction. To avoid this potential interaction, separate the time you take magnesium supplements from any fiber-rich foods.

Common side effects of magnesium supplements include gastrointestinal symptoms such as nausea, vomiting, or diarrhea. If you experience any of these side effects, taking the supplement with food may help.

Drugs and supplements that may interact with magnesium include:

Bisphosphonates: Bisphosphonates treat and prevent osteoporosis. Examples include Fosamax (alendronate) and Boniva (ibandronate). Magnesium can decrease how well a bisphosphonate is absorbed (broken down in the body). You should separate bisphosphonate and magnesium supplement doses by at least two hours.
Certain antibiotics: Magnesium can decrease the absorption of certain antibiotics, like Vibramycin (doxycycline) and Ciproxin (ciprofloxacin). This can lead to the antibiotic not working as well. If prescribed these medications, take the antibiotic one hour before or two hours after a magnesium supplement.
Diuretics: Diuretics, or water pills, are medications used to help your body get rid of extra fluid. Examples include hydrochlorothiazide, Lasix (furosemide), and Aldactone (spironolactone). Certain diuretics, including hydrochlorothiazide, may lower your magnesium level. Other diuretics, like Aldactone, may increase your magnesium level.
Calcium: High doses of calcium can decrease how well your body absorbs magnesium. Both calcium and magnesium compete for absorption in the same area of the gastrointestinal tract. Consider taking them at separate times of the day.
Zinc: High doses of zinc can decrease how well your body absorbs magnesium. Zinc and magnesium compete for absorption in the same area of the gastrointestinal tract. If taking magnesium with a high zinc dose (larger than 142 milligrams a day), consider taking them at separate times of the day.

Talk with your healthcare provider about any medications or supplements you may be taking. They can help you determine if they interact with magnesium and how to space out your medications to avoid interactions.

Magnesium is found in certain foods, medications, and supplements. It is involved in numerous body functions, including energy production, bone health, and muscle and nerve health.

Most people can obtain magnesium through their diet, but many may benefit from taking a magnesium supplement. The best time to take a magnesium supplement depends on the type of magnesium and its intended use.