Ghost Fitness/Magnesium/What is the downside of taking magnesium citrate?
What is the downside of taking magnesium citrate?
The short answer
The main downside is the moderate laxative effect, which forbids citrate before a session and at bedtime and makes it a daytime rest-day salt; the second is its low magnesium fraction, about 16%, which means big tablets or several capsules; the third is the sugar of the gummies it usually comes in. Not downsides: constipation, where the effect is an upside, and kidney stones, which citrate protects against.
- Downside one: the laxative effectmoderate; arrives within hours; forbids citrate before a session and at bedtime
- Downside two: the fractionabout 16% magnesium by weight: 300mg elemental needs about 1900mg of citrate, big tablets or several capsules
- Downside three: the gummiescitrate is the gummy salt; 50mg per gummy in sugar; six for a dose
- Not downsidesconstipation, where the effect helps; kidney stones, which citrate protects against
Our brand: the worked example on this page
Futuro Labs Magnesium Glycinate
- 22p a day
- 180 capsules, 2 capsules daily
- Lab tested
- Made in the UK
The salt without the citrate downsides: Futuro Labs Magnesium Glycinate on Amazon UK, bisglycinate, 300mg elemental at 80% NRV over 2 capsules, £19.99 for 90 days at 22p. Full label breakdown. The citrate-for-athletes decision is on the citrate athletes page; the citrate sleep page on the citrate sleep page.
The three downsides, the laxative effect first because it sets the clock
What is the downside of taking magnesium citrate is a question with three honest answers and two false ones, and the first honest answer sets the clock for the salt. The laxative effect: magnesium citrate carries a moderate osmotic effect, more than bisglycinate and less than oxide, arriving within hours of a dose that exceeds what the gut absorbs, and for an athlete that effect has a schedule, forbidding citrate before a session, a long run or a race, where its arrival mid-effort is the runner's trots, and at bedtime, where it is the small-hours bathroom trip that the citrate-sleep page describes, so that citrate is a daytime salt for a rest day or a reader who tolerates it, and the section's default is bisglycinate for the reader who wants one salt at one anchor, the evening meal. The magnesium fraction: citrate is about 16% magnesium by weight, so a full 300mg elemental dose needs about 1900mg of the compound, which is either a large tablet or two, a heaped scoop of powder or three or four capsules, the citrate-versus-glycinate pages' note that citrate's format is bulkier for the same magnesium and that a front label reading 500mg citrate delivers about 80mg of the mineral, the 300mg-of-what trap in citrate form. The gummies: citrate is the salt that goes into gummies, because it tolerates the sugar-and-gelatin matrix, and a gummy carries about 50mg of elemental magnesium in several grams of sugar, so a lifter's dose is six gummies and their sugar, a downside for the teeth, the calories and the arithmetic, the gummy pages' finding.
The two things that are not downsides, the citrate decision, and the list filed
Two things that get listed as citrate's downsides are not. Constipation: for a reader who is both short of magnesium and constipated, common on a low-fibre cut, the laxative effect is the benefit rather than the side effect, citrate softening stool and speeding transit by the same osmotic mechanism that is a licensed medicine's use in magnesium hydroxide, the bowel-issues page's one honest case, so the main downside becomes citrate's one indication and the reader for whom it is the right salt. Kidney stones: the folklore worries that a citrate supplement forms stones, and the literature says the opposite, urinary citrate inhibiting calcium stone formation and magnesium citrate having been studied as a stone-preventing agent, so citrate is if anything protective and the fear is a confusion with calcium oxalate, not a downside. Two smaller notes for completeness: citrate powders are acidic and a reader who sips one through the day rinses afterward for the enamel's sake, and a citrate dose is spaced from the same medicines any magnesium is, the chelated antibiotics, bisphosphonates, levothyroxine and gabapentin, no more and no less than bisglycinate. The citrate decision follows from the list: citrate is fine with a daytime meal on a rest day for a reader who tolerates it, is the right salt for a constipated reader, is the wrong salt before a session and at night, and is bulkier and sweeter per milligram than a bisglycinate capsule, the claims being the mineral's and identical in every salt. The list filed: the laxative effect and the hours it forbids, the 16% fraction and the tablets it makes, the sugar of the gummies, and two false downsides, constipation as an upside and kidney stones as a protection, with the worked example being the salt without the citrate downsides, bisglycinate at 300mg elemental over two capsules, £19.99 for 90 days at 22p.
| The item | The finding | The consequence |
|---|---|---|
| The laxative effect | Moderate; within hours of a dose exceeding absorption | Not before a session; not at bedtime; a daytime rest-day salt |
| The fraction | About 16% magnesium by weight | Big tablets, a heaped scoop or several capsules for 300mg |
| The gummies | The gummy salt; about 50mg per gummy in sugar | Six for a dose; teeth, calories, arithmetic |
| Constipation | The effect is the benefit | Citrate's one indication; an upside |
| Kidney stones | Citrate inhibits stone formation | A protection, not a downside |
| The claims | The mineral's; identical in every salt | The salt decides tolerance and format only |
The verdict, three downsides, one of them an upside for some, and a fear to retire
What is the downside of taking magnesium citrate: its moderate laxative effect, which arrives within hours and forbids citrate before a session and at bedtime, making it a daytime rest-day salt; its low magnesium fraction of about 16%, which makes a full dose a large tablet, a heaped scoop or several capsules; and the sugar of the gummies it usually comes in, with two false downsides retired, constipation, where the effect is citrate's one honest indication, and kidney stones, which citrate protects against rather than causes. The salt without the citrate downsides: Futuro Labs Magnesium Glycinate, bisglycinate, 300mg elemental at 80% NRV over two capsules, £19.99 for 90 days at 22p a day.
What to check on the label
- Respect the laxative effect's clock: not before a session, not at bedtime.
- Do the fraction's arithmetic: about 16%; read the %NRV.
- Count the gummy sugar: six gummies for a dose.
- Use the effect for constipation: citrate's one indication.
- Retire the stone fear: citrate protects.
Our brand
The worked example: Futuro Labs Magnesium Glycinate
Futuro Labs Magnesium Glycinate is the worked example for magnesium reviews because its label states every number a review needs: 1500mg magnesium bisglycinate at 20%, 300mg elemental, 80% NRV, 2 capsules a day, 180 capsules for £19.99, 22p a day, UK made, vegan HPMC shell, batch tested for lead, mercury, arsenic and cadmium, and only the register's own magnesium claims printed.
- Elemental magnesium per serving
- 300mg (80% NRV)
- Form
- magnesium bisglycinate 20%
- Serving
- 2 capsules a day
- Bottle
- 180 capsules, 90 days
- Price
- £19.99 (22p a day)
- Capsule
- vegetarian shell, vegan product
Questions people also ask
Is magnesium citrate bad for you?
No: its downsides are a moderate laxative effect that forbids it before a session and at bedtime, a low magnesium fraction that makes big tablets, and the sugar of the gummies it comes in, while the claims are the mineral's and identical in every salt.
Does magnesium citrate cause kidney stones?
No, the opposite: urinary citrate inhibits calcium stone formation and magnesium citrate has been studied as a stone-preventing agent, so the fear is a confusion with calcium oxalate and citrate is if anything protective.
Why does magnesium citrate cause diarrhoea?
A dose exceeding what the gut absorbs draws water into the bowel osmotically, citrate carrying a moderate version of the effect, more than bisglycinate and less than oxide, arriving within hours, which is why it suits a constipated reader and not one taking it before training or at night.
How much magnesium is in 500mg of magnesium citrate?
About 80mg of elemental magnesium at citrate's roughly 16% fraction, around 21% of the reference value, so a full 300mg dose needs about 1900mg of the compound, the arithmetic the %NRV line beside the figure confirms.
When is magnesium citrate the right choice?
With a daytime meal on a rest day for a reader who tolerates it, and especially for a reader who is both short of magnesium and constipated on a low-fibre cut, where the laxative effect is the benefit; bisglycinate is the salt for a session-adjacent or nightly habit.
Sources
- Walker AF, Marakis G, Christie S, Byng M. Mg citrate found more bioavailable than other Mg preparations in a randomised, double-blind study. Magnesium Research 2003;16(3):183-191. PubMed record
- The citrate and kidney stone literature: urinary citrate inhibits calcium stone formation, and magnesium citrate has been studied as a stone-preventing agent, so the citrate salt is if anything protective against stones rather than a cause. PubMed record
- The magnesium absorption literature: fractional absorption of magnesium falls as the dose rises, so the same daily amount taken in divided doses is absorbed at a higher fraction and with less osmotic laxative effect than a single large dose. PubMed record
- The NICE constipation guidance: osmotic laxatives, including magnesium hydroxide, are established treatments for constipation in adults after dietary and fluid measures, magnesium's laxative effect being a licensed medicinal use rather than a supplement claim. https://cks.nice.org.uk/topics/constipation/