When to Take Magnesium for Sleep (and Which Kind to Choose)
By Mark from Outback, The Outback Series customer care7 min read
The short answer
- Take it in the evening, about 30 to 60 minutes before bed. With a small snack if your stomach is sensitive. Taking it at the same time every night matters more than the exact minute.
- Choose a well-absorbed form such as magnesium glycinate (bisglycinate) or citrate. Magnesium oxide is cheaper but less well absorbed and more likely to loosen your stools.
- Adults should keep magnesium from supplements to 350 mg a day or less unless a doctor tells you otherwise. Check with your doctor first if you have kidney problems or take antibiotics, osteoporosis medicine, diuretics or acid-reflux medicine.
Why magnesium and sleep come up together
Magnesium is a mineral your body uses in hundreds of processes, including normal muscle and nerve function. Many adults eat less of it than recommended, and older adults are more likely to fall short.
That is why magnesium has become a popular part of evening routines. The research is still modest: a 2021 review of trials in older adults found the evidence promising but low quality, based on a handful of small studies. So think of magnesium as one piece of a good evening routine, not a switch that turns sleep on.
When to take magnesium for sleep
- In the evening, 30 to 60 minutes before bed. This is the most common approach, and it fits naturally into a wind-down routine.
- With a small snack if magnesium bothers your stomach on its own.
- If your serving is several capsules, you can take them together in the evening or split them between dinner and bedtime. Follow your label.
- Every night, at about the same time. Consistency beats timing. Many people give a new routine two weeks before judging it.
- Keep it apart from certain medicines. Some antibiotics and osteoporosis medicines absorb poorly if taken close to magnesium. Ask your pharmacist how many hours to leave between them.
Which kind of magnesium is best?
| Form | Absorption | Good to know |
|---|---|---|
| Glycinate / bisglycinate | Well absorbed | Gentle on the stomach. A popular choice for evenings. |
| Citrate | Well absorbed | Can loosen stools at higher amounts. |
| Oxide | Lower | Inexpensive and common in cheap multivitamins. Most likely to cause loose stools. |
| Chloride, lactate, aspartate | Well absorbed | Less common in sleep formulas. |
| Threonate | Varies | Expensive, marketed for the brain. Limited research. |
The US National Institutes of Health notes that citrate, aspartate, lactate and chloride forms are absorbed better than oxide and sulfate. Glycinate is widely used in evening formulas for how gentle it is.
How much magnesium is too much?
- Daily needs for adults 51 and older: about 420 mg for men and 320 mg for women, from food and supplements combined.
- The upper limit from supplements: 350 mg a day for adults, unless your doctor recommends more.
- Too much usually shows up as loose stools, nausea or stomach cramps. Very high amounts can be dangerous, especially for people with kidney problems.
Food counts too. Pumpkin seeds, almonds, cashews, spinach, black beans, edamame, peanut butter and whole grains are all good sources.
Check with your doctor first if you
- Have kidney problems
- Take antibiotics or osteoporosis medicine (magnesium can reduce how well they absorb)
- Take diuretics (water pills) or long-term acid-reflux medicine, which can change your magnesium levels
- Are pregnant or nursing, or take several prescriptions
Pair it with a better evening routine
- Go to bed and get up at the same time every day, weekends included.
- Dim the lights and put the phone down 30 minutes before bed.
- Keep the bedroom cool, dark and quiet.
- Try a warm shower or a five-minute foot massage before bed.
- Go easy on caffeine after lunch and on alcohol in the evening.
Mark's tipCustomers who stick with magnesium tell me the same thing: they tie it to something they already do every night, like brushing their teeth. Keep the bottle next to the toothbrush and you will not forget it.
Our magnesium: Outback Magnesium+
Outback Magnesium+
300 mg of magnesium per 3-capsule serving from magnesium citrate and bisglycinate chelate, plus vitamins B6 and B12, folate, zinc, and a blend of cramp bark and passionflower. Made in the USA. Made to support relaxation and restful sleep.* Covered by our 365-Day Returnless Refund.
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See Magnesium+Frequently asked questions
Is it better to take magnesium at night or in the morning?
For sleep, most people take it in the evening, 30 to 60 minutes before bed. If it upsets your stomach, take it with a small snack or with dinner.
How long before bed should I take magnesium?
About 30 to 60 minutes. Taking it at the same time every night matters more than the exact timing.
Which is better for sleep, magnesium glycinate or citrate?
Both are well absorbed. Glycinate is gentler on the stomach, which is why many evening formulas use it. Citrate can loosen stools at higher amounts. Some formulas, including Outback Magnesium+, combine both.
Can I take magnesium every night?
Many adults do. Keep magnesium from supplements to 350 mg a day or less unless your doctor advises otherwise, and check with your doctor if you have kidney problems or take other medications.
Can magnesium upset your stomach?
It can, especially the oxide form or large amounts of citrate. Taking it with food or switching to glycinate often helps.
Does magnesium interact with medications?
Yes. It can reduce absorption of some antibiotics and osteoporosis medicines, and diuretics and long-term acid-reflux medicines can affect your magnesium levels. Ask your pharmacist about timing.
More Outback guides
Sources: Magnesium fact sheet for consumers, NIH Office of Dietary Supplements; Mah J, Pitre T. Oral magnesium supplementation for insomnia in older adults: a systematic review and meta-analysis. BMC Complementary Medicine and Therapies, 2021.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This guide is general information, not medical advice. Talk with your doctor before starting a supplement, especially if you take medications.