If you’ve recently started taking magnesium and noticed you’re peeing more often, you may be wondering: Does magnesium make you pee?
While magnesium can affect your bowel movements, it isn’t generally known to increase urine production or affect bladder function. If you started taking it at night for sleep and you're now up at 2 a.m., there's usually a simpler explanation, and one common culprit is the glass of water you took it with.
Here’s how magnesium affects your body, why it’s not usually associated with increased urination, and common side effects to know about. For the bigger picture on where magnesium fits among sleep supplements, start here.
Key Takeaways
- Magnesium is not a diuretic and does not typically make you urinate more. If you're getting up at night, one common culprit is the water you took it with.
- Magnesium's better-known digestive effect is on the bowel, not the bladder, and how much it affects you depends on the amount, the form, and the person.
- Your kidneys do excrete excess magnesium in urine, but that's normal mineral regulation rather than a diuretic effect.
- Taking magnesium earlier in the evening, mixed the way the label directs, may help you avoid the middle-of-the-night wake-up.
- Any persistent change in urination is worth mentioning to your healthcare provider rather than self-diagnosing.
As always, consult with your healthcare provider before starting any new supplement or nutrition program, especially if you are pregnant, nursing, taking medication, or have a medical condition.
In this article:
- Does Magnesium Make You Pee?
- Why You Might Be Peeing More After Starting Magnesium
- Is Magnesium a Diuretic?
- What Are the Actual Side Effects of Magnesium?
- How to Take Magnesium Without the 2 a.m. Wake-Up
- When to Talk to Your Healthcare Provider
Does Magnesium Make You Pee?
No, magnesium is not considered a diuretic and does not typically increase urination for most people. However, there are a few reasons you might notice more nighttime bathroom trips after starting it.
The short answer
Diuretics are medications and natural substances that increase urination. Caffeine is one example of a natural compound with diuretic properties.
Magnesium supplements have a few documented side effects, but increased urination isn’t one of them.
Why people think it does
The confusion over magnesium supplements making you pee may come from magnesium’s impact on the gastrointestinal system.
Magnesium salts that aren't fully absorbed, such as magnesium oxide, stay in the gut and pull water in with them, which speeds things along and can loosen stools. This is why magnesium supplements can come with gastrointestinal side effects, like diarrhea.
Although this effect occurs in the digestive tract rather than the urinary system, it can lead to more frequent trips to the bathroom because of diarrhea or loose stools.
If you notice more frequent urination after starting a magnesium supplement, another factor is likely to blame.
Why You Might Be Peeing More After Starting Magnesium
A few things can explain extra bathroom trips after starting magnesium: the water you take it with, the form of magnesium you chose (which affects your stool, not your bladder), or a coincidence of timing that has nothing to do with the supplement.
It could be the water
One common culprit is the water you take it with. Magnesium supplements are usually taken with water, so if you increase your water intake, you’ll likely notice increased urination.
This may be especially noticeable at night if you take magnesium before bed with a full glass of water. If this is a new routine, you may find that you have to get up a few hours later to use the bathroom.
If the increased nighttime urination is bothering you, try taking your supplement earlier in the evening and cutting back on other drinks in the hours before bed.
The form you’re taking
There are several forms of magnesium used in supplements, including magnesium glycinate, magnesium citrate, and magnesium oxide.
Some forms, such as magnesium oxide, can impact your digestive system, drawing water into the intestines and triggering loose stools. These effects are more common at higher doses and vary from person to person.
Making more trips to the bathroom may make you think that magnesium supplements are also making you pee more.
If you’re experiencing digestive side effects after taking magnesium, talk with your healthcare provider about trying a smaller amount or a different form.
Timing and coincidence
Lastly, if you find yourself peeing more after starting magnesium, it may be a simple coincidence.
You may have recently become more interested in your overall health, including supplements, diet, and hydration. This may lead to drinking more water or eating more hydrating foods, which could result in increased urination.
Alcohol and caffeine can also increase urination, as can certain medications.
If your increased urination persists, talk with your healthcare provider to rule out other causes.
Is Magnesium a Diuretic?
Magnesium is not classified as a diuretic. The relationship between magnesium and urination runs the other direction. Your kidneys do filter and excrete excess magnesium in urine as part of normal mineral regulation, rather than magnesium causing you to produce more urine.
How your body regulates magnesium
Magnesium levels are tightly regulated by your body to keep blood levels within a specific range. That regulation is one piece of what magnesium does in the body, which extends well beyond the digestive and kidney effects covered here.
Magnesium is mainly regulated by your kidneys, which filter your blood and either reabsorb or excrete magnesium in the urine, depending on your body’s needs.
If your magnesium levels are low, your kidneys reduce how much magnesium is lost in the urine. When you have more than you need, they release the extra in your urine. This keeps your magnesium levels within a healthy range.
The difference between excretion and a diuretic effect
The distinction comes down to volume versus content. A diuretic changes how much urine your body makes. It acts on the kidney to increase fluid output. Magnesium excretion changes what's in the urine: your kidneys are clearing a mineral you already have enough of, without changing the amount of fluid leaving your body.
That's why finding magnesium in urine doesn't make magnesium a diuretic. It's the same reason your urine contains sodium and potassium without either of those being a diuretic. The mineral is passing through as part of normal regulation.
What Are the Actual Side Effects of Magnesium?
The most common magnesium side effects are digestive, including loose stools or stomach upset, particularly at higher doses and with forms like magnesium oxide, not increased urination.
Most common side effects
The most common side effects related to taking magnesium supplements include:
- Diarrhea
- Nausea
- Abdominal cramping
- These side effects are commonly associated with certain forms of magnesium, such as magnesium oxide. Side effects are also more likely when magnesium supplements are taken in higher doses.
What forms are gentler
Some forms of magnesium are less likely to cause gastrointestinal side effects. For example, magnesium glycinate is a highly bioavailable form that's well absorbed and gentle on the stomach.
It’s well-tolerated and is less likely to cause gastrointestinal side effects like diarrhea and nausea than other forms, such as magnesium oxide and magnesium sulfate.
How to Take Magnesium Without the 2 a.m. Wake-Up
Take it earlier in the evening rather than right at bedtime, mix it the way the label directs, and if digestive effects are part of the picture, talk with your healthcare provider about a smaller amount or a different form.
Timing
Rather than taking your magnesium supplement with a full glass of water when you get into bed, consider taking your magnesium earlier in the evening. This gives your body time to hydrate and produce urine before you get into bed.
1st Phorm Magnesium is a powder mixed in eight ounces of water, so this timing shift matters more than it would for a capsule. As with any supplement, follow the directions on the label rather than adjusting the dose on your own.
How much water
If you're taking magnesium before bed and getting up at night, look at how much water goes in with it. With capsules, you only need enough to swallow them, not a full glass. With a powder, mix it the way the label directs and rely on the timing adjustment above instead.
Choosing a form
If digestive effects have been part of the picture, the form matters (see the breakdown above). Gentler forms are less likely to draw water into the intestine, which means fewer trips for loose stools. If you're still deciding, how to choose a magnesium supplement breaks the options down.
When to Talk to Your Healthcare Provider
A persistent change in how often you urinate is worth mentioning to your healthcare provider, since it can have a range of explanations that have nothing to do with a supplement.
Magnesium supplements aren’t typically associated with changes in urination. If you’re experiencing increased urination, it may be due to something else, such as an underlying medical condition.
If your increased urination persists, it’s a good idea to make an appointment with your healthcare provider to rule out potential causes.
Conclusion
Magnesium isn’t a diuretic and magnesium supplements aren’t typically associated with increased urination.
If you’re peeing more after starting a magnesium supplement, it’s more likely that another cause, such as increasing your water intake, is the issue.
Taking your magnesium earlier in the evening, mixed the way the label directs, could help reduce nighttime trips to the bathroom. If you're building out an evening routine more broadly, our nighttime supplements collection is a reasonable starting point. If your increased urination persists, talk with your healthcare provider to rule out other potential causes.
If you have any questions in the meantime, don't hesitate to reach out. We have a full team of NASM Certified Personal Trainers and Nutrition Coaches right here in St. Louis, Missouri.
Just give us a call at 1-800-409-9732 or send us an email at [email protected]. We're available Monday through Friday from 6 AM to 8 PM Central and Saturday & Sunday from 9 AM to 7 PM Central.
We'll be more than happy to help in any way we can!
Frequently Asked Questions
Why do I wake up at night after taking magnesium?
One common culprit is the water, not the magnesium. Supplements are usually taken with water, and a glass of water at 10 p.m. can have a predictable result a few hours later. Try taking your magnesium earlier in the evening, mixed the way the label directs.
Does magnesium glycinate make you pee?
No. Magnesium glycinate isn't a diuretic and isn't associated with increased urination. It's also one of the gentler forms on the digestive system, so it's less likely than forms like magnesium oxide to cause loose stools.
What are the side effects of taking magnesium every day?
Certain forms of magnesium, like magnesium oxide, could cause diarrhea and other gastrointestinal disturbances, especially in higher doses. Follow the directions on your product label, and talk with your healthcare provider if side effects persist.
Should I take magnesium in the morning or at night?
You can take magnesium any time of day. Many people take it in the evening, and in one randomized trial, adults with poor sleep who took magnesium bisglycinate reported slightly fewer sleep problems than those taking a placebo.*
*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.
