What’s the Best Time to Take Magnesium Supplements?

You can take magnesium supplements at any point during the day, but depending on your goal for using them, you might prefer a particular routine. More important than the exact hour is often taking them regularly.

Magnesium is a vital mineral involved in numerous health processes. It may help regulate blood sugar, prevent migraine episodes, lower blood pressure, enhance athletic performance, and reduce the risk of depressive and anxious symptoms.

The recommended dietary allowance (RDA) for magnesium for adults is 310–420 mg per day. This amount is adequate for nearly all healthy people.

Although many can meet their magnesium needs through diet alone, supplements may be necessary in some situations, especially if you are deficient.

Does timing matter for magnesium?

In terms of how magnesium affects the body, the time you take it doesn’t substantially change its effects. You’ll receive similar benefits whether you take it in the morning, afternoon, or evening.

Still, you might choose a specific schedule based on why you’re taking magnesium and how it affects you personally.

One important point is that whether you’re using magnesium to lift mood, ease anxiety, or improve sleep, the benefits are tied to consistent, long-term use. In short, taking magnesium sporadically is less likely to yield the full benefits.

MORE ON THIS: The types of magnesium and what to use each for.

Taking magnesium in the morning

Taking magnesium first thing can be the simplest way to remember and may support adherence to long-term supplementation. This can be useful if you’re correcting a magnesium deficiency or using it to lower the likelihood of migraine attacks.

Morning magnesium may also be beneficial if you want to begin the day feeling more relaxed or wish to reduce muscle tension, cramps, or pain.

Taking magnesium at bedtime

Magnesium can promote relaxation both physically and mentally. Research indicates it can enhance sleep quality for some individuals, especially those with insomnia. For better sleep, consider taking magnesium a couple of hours before bed. Conversely, avoid taking it when you need to be fully alert soon afterward (for instance, just before driving long distances).

Magnesium supplements may also help with constipation. If that’s your aim, taking it at night may be preferable, since it can take several hours to take effect. If constipation is not a concern, taking magnesium with meals can help minimize side effects such as diarrhea or stomach upset.

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 reflect the views of our medical experts. This content is informational and should not be taken as medical advice.

Possible magnesium interactions

Magnesium supplements can interfere with the absorption of other supplements and medications, potentially reducing their effectiveness.

Certain drugs may also boost magnesium elimination through the urine, which could diminish the amount retained if taken concurrently.

For instance, take antibiotics at least 2 hours before or 4 to 6 hours after a magnesium supplement to avoid lowering the antibiotic’s effectiveness. If you take bisphosphonates, separate them from magnesium by at least 2 hours. And if you use diuretics or proton pump inhibitors, discuss timing with your healthcare provider to find the best schedule for magnesium.

Whenever you start a new prescription or begin magnesium supplementation, it’s wise to ask your clinician about possible interactions and the optimal timing for taking magnesium.

MORE ON THIS: How much magnesium should you take per day?

The bottom line

Overall, there is no single “best” time to take magnesium supplements. The timing can depend on your reason for taking them, other medications that may interact, and your healthcare provider’s guidance. The key is to take your supplement consistently.