You can take magnesium supplements at any time of the day, but depending on what you’re taking them for, you may want to have a specific schedule. Consistency may be more important than time of the day, though.

Magnesium is an important mineral involved in many aspects of health. It may help improve blood sugar, prevent migraine attacks, reduce blood pressure, boost athletic performance, and lower the chance of depression and anxiety symptoms.

The recommended dietary allowance (RDA) for magnesium is 310–420 mg daily for adults. This is sufficient magnesium for nearly all healthy individuals.

While most people can meet their magnesium needs through food sources alone, supplements may be necessary in some cases, particularly if you’re deficient in the mineral.

It does not matter what time of day you take magnesium, in terms of its effect on the body. You will experience the same effects whether you take the supplement in the morning, afternoon, or evening.

But, although magnesium supplements may be taken at any time of the day, you may prefer to have a specific schedule based on your reason for taking them and the effects they have on you.

One thing to note is that whether you’re taking magnesium to improve your mood, decrease anxiety, or enhance sleep quality, the benefits of magnesium supplements are all associated with consistent long-term use. In other words, you may not experience the full benefits if you only take magnesium sometimes.

Taking magnesium in the morning

Taking magnesium first thing in the morning may be easiest to remember and may help you adhere to long-term use. This could be helpful if you are managing a magnesium deficiency or may use it to reduce the chance of migraine attacks.

Taking magnesium in the morning may also help if you’d like to start your day feeling relaxed or reduce muscle tension, cramps, or pain.

Taking magnesium at bedtime

Magnesium may have a relaxing effect, both physically and mentally. Research also suggests it can improve the quality of sleep for some people, particularly those with insomnia. For a good night’s sleep, you may prefer taking magnesium a couple of hours before bedtime. In the same way, you want to avoid taking it if you need to be fully alert (like right before a road trip).

Magnesium supplements may also help relieve constipation. If you take magnesium for this purpose, you may want to take it at bedtime, since it may take a few hours for the supplement to take effect. If you don’t have constipation, you may want to take magnesium at meal times to avoid side effects like diarrhea and nausea.

Medical perspective

“Everyone responds to the various forms of magnesium differently. Magnesium forms with the best absorption potential include magnesium malate, magnesium glycinate, and magnesium citrate, although this last one has a modest laxative effect. Magnesium oxide, although more affordable, is hardly absorbed and the laxative effect is quite strong.”

Meredith Goodwin, MD, FAAFP

Quotes represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

Magnesium supplements may interfere with the absorption of other supplements as well as medications, potentially reducing their effectiveness.

Some medications may also increase magnesium excretion through urine, which could offset the dose you’re taking if you take them at the same time.

For example, you should take antibiotics at least 2 hours before or 4 to 6 hours after taking a magnesium supplement to avoid the chance of reducing the antibiotic’s effect. If you use bisphosphonates, you should take magnesium supplements at least 2 hours before or after these medications. And, if you’re taking diuretics or proton pump inhibitors, it’s best to consult a healthcare professional to determine the best schedule for your magnesium supplements.

If you get a new prescription from a healthcare professional, or you just started taking magnesium, it’s a good idea to ask the doctor about potential interactions and the best time of the day to take your magnesium supplements.

In sum, there’s no “best” time to take magnesium supplements. The schedule may depend on what you’re taking them for, other drugs you take that may interact with them, or your doctor’s recommendations. The most important thing is to remain consistent in taking your supplement.