Best Magnesium for IBS-C and Constipation: What Reddit Owners Report
Among magnesium options, Magnesium oxide has the best reports from people with IBS-C or constipation: 67 of 78 rated owner comments were positive. We rank by a context rating that pulls small samples toward the average, so a handful of glowing comments cannot top the list. Only options with at least 5 rated comments in this context are ranked. This is a summary of self-reports, not a recommendation, and it is not evidence that any of them works for you.
| # | Supplement | Context rating | Rated comments here | Positive | Negative | Unwanted effects | Overall score |
|---|---|---|---|---|---|---|---|
| 1 | Magnesium oxide | 3.8 | 78 | 67 | 7 | 7 | 4.0 |
| 2 | Magnesium glycinate | 3.7 | 38 | 31 | 4 | 0 | 3.7 |
| 3 | Magnesium citrate | 3.4 | 234 | 153 | 57 | 12 | 4.0 |
Why each ranks where it does
1. Magnesium oxide
67 positive and 7 negative out of 78 rated comments from people with IBS-C or constipation; 86% positive. How people take it: Magnesium oxide dosage and timing.
4/5“Now at 32 I have not had an attack like this in almost a year whilst taking 400mg of magnesium oxide every night before bed..”
1/5 Pain & crampingRegularity“I take a daily magnesium oxide supplement every night before bed.”
2. Magnesium glycinate
31 positive and 4 negative out of 38 rated comments from people with IBS-C or constipation; 82% positive. How people take it: Magnesium glycinate dosage and timing.
4/5“When I started taking Magnesium glycinate I started going to the toilet more and it helped my symptoms.”
2/5“I stopped taking it & instead took some fiber gummies in the morning & magnesium glycinate at night.”
3. Magnesium citrate
153 positive and 57 negative out of 234 rated comments from people with IBS-C or constipation; 65% positive. See Magnesium citrate side effects. How people take it: Magnesium citrate dosage and timing.
4/5“Today I would take some magnesium citrate, because wherever is fermenting in your gut needs to be released not stuck up inside of you.”
2/5“Taking more and more laxatives, drinking Magnesium Citrate as a last resort, NEVER AGAIN.”
Safety notes
- Magnesium oxide: The NIH upper limit for supplemental magnesium is 350 mg a day for adults unless a doctor advises more; people with kidney disease are at higher risk of magnesium build-up.[NIH Office of Dietary Supplements]
- Magnesium oxide: Magnesium can interfere with some antibiotics and bisphosphonates; space doses apart.[NIH Office of Dietary Supplements]
- Magnesium glycinate: The NIH upper limit for supplemental magnesium is 350 mg a day for adults unless a doctor advises more.[NIH Office of Dietary Supplements]
- Magnesium citrate: The NIH upper limit for magnesium from supplements is 350 mg a day for adults unless a doctor advises more; the risk of magnesium toxicity rises with kidney disease.[NIH Office of Dietary Supplements]
Check interactions with a pharmacist before starting, and see a doctor about new or severe symptoms.
Example Magnesium oxide products
Examples sold on Amazon, not ranked by Reddit. The score above is for the ingredient, not these products.
Nature Made Magnesium Oxide Extra Strength 400 mg, 60 Softgels
Rugby Magnesium Oxide 400 mg Tablets, Dietary Supplement, Gluten-Free
Keep comparing
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- Magnesium citrate vs Magnesium oxide
- Magnesium citrate vs Magnesium glycinate
- Magnesium oxide vs Magnesium glycinate
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- Background: Magnesium Forms Compared
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