Supplement evidence

053 / 575Mineral form

Magnesium oxide

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The short answer

A poorly absorbed form used clinically as an antacid or laxative and sometimes for replacement.

Evidence and scope: Established for an indicated use
This status does not grade the ingredient for every goal, outcome, or person.
Important limitation: The benefit is tied to the stated indication, dose, and population; it is not evidence of broader disease prevention or longer life.
Before deciding: Key concern: Kidney impairment markedly increases hypermagnesemia risk; separate antibiotics and thyroid medicine.

01 / PRACTICAL GUIDE

Dose, absorption, and combinations

These are indication-specific reference or studied ranges—not a personalized prescription. Start with the objective, then check the form, label, medicines, and health conditions.

Reference range by objective

ConstipationProduct- and clinician-directed; dose by elemental magnesium

Reference or studied range—not a personalized prescription. The product label or a clinician may specify a different dose.

Dose source ↗

More is not automatically better. A clinician or product label may specify a different amount.

Absorption / solubilityFormulation-dependent

Not usefully classified as a fat- or water-soluble vitamin; absorption depends on the salt, extract, delivery system, and meal.

How it is commonly taken

Take with a full glass of water.

Do not combine casually

Kidney impairment markedly increases hypermagnesemia risk; separate antibiotics and thyroid medicine.

Dose and use source ↗

Dose and use links lead to primary or official source material. Search links are discovery tools, not proof that every returned paper applies.

02 / EVIDENCE

What the research says

We keep supportive, mixed, negative, safety, and contextual findings together. The headline never replaces the underlying papers.

3research papers in this ledger

3unique primary studies represented

325unique participants represented

These are audited counts for this JIVANA collection, not search-result totals. Participants are counted once when multiple papers use the same cohort; review papers are not added again to participant totals.

Open the research timelineResearch timeline

Entries are ordered by publication year. A study period appears only when the source reports it.

2021

Supports a specific usePMID 32969946

Senna Versus Magnesium Oxide for the Treatment of Chronic Constipation

Overall response was 68.3% with magnesium oxide and 11.7% with placebo; bowel movements and quality of life also improved. No severe treatment-related adverse events occurred during this short trial.

Published: 2021Duration: 28 daysn=90 participants

Study design and methods

Design: Randomized, double-blind, placebo-controlled trial
Population: 90 adults with chronic idiopathic constipation; 93% women
Intervention: Magnesium oxide 1.5 g/day, senna 1 g/day, or placebo
Outcome: Overall symptom response, bowel movements, constipation-related quality of life, and severe treatment-related adverse events

Open research record ↗

2021

Mixed or qualifiedPMID 34719399 · NCT03807219

Magnesium oxide monohydrate in the treatment of nocturnal leg cramps

Both groups improved, but cramp episodes fell somewhat more with magnesium oxide monohydrate (-3.4 versus -2.6); duration and sleep quality also favored treatment. The registration was retrospective and 19% did not complete.

Published: 2021Duration: 60 daysn=175 participants

Study design and methods

Design: Randomized, double-blind, placebo-controlled multicenter trial
Population: 216 adults screened; 175 completed
Intervention: Magnesium oxide monohydrate 226 mg nightly or placebo
Outcome: Nocturnal leg-cramp frequency and duration, sleep quality, pain, and quality of life

Funding or conflict note: The trial was retrospectively registered. PubMed records the authors as declaring no conflict of interest.

Open research record ↗

2020

Mixed or qualifiedPMID 31952280

Lactobacillus reuteri DSM 17938 and Magnesium Oxide in Children with Functional Chronic Constipation

All groups increased defecation frequency, while the two magnesium-oxide groups softened stool. Magnesium oxide also changed microbiome composition; the small three-arm study did not establish comparative long-term safety.

Published: 2020Duration: 4 weeksn=60 participants

Study design and methods

Design: Randomized, double-blind, placebo-controlled three-group trial
Population: 60 children aged over 6 months and under 6 years with functional constipation
Intervention: L. reuteri plus placebo, L. reuteri plus magnesium oxide, or placebo plus magnesium oxide
Outcome: Defecation frequency, stool consistency, and gut microbiome

Funding or conflict note: BioGaia funded the trial; the PubMed record states the funder had no role in design, analysis, interpretation, writing, or publication decisions.

Open research record ↗

Unscreened discovery appendix—not evidence196 candidate publicationsSearch run: Aug 21, 2026

Complete for the displayed PubMed query at the search timestamp—not for all databases or every possible synonym. Candidates can be irrelevant, duplicate the same study, or report negative findings. They are never summed as evidence or participants until screened.

03 / SOURCES

Start with the source material

Official evidence overviewPubMed bounded human-evidence search Live PubMed discovery searchNational Library of Medicine

The live search is for discovery only. Search-result counts change and are not included in the audited totals above.

Recent PubMed discovery recordsDirect links to the first 12 records returned by the reproducible search. These are discovery candidates—not reviewed summaries or a count of supportive findings.

04 / EXPERT CONTEXT

Expert context—not evidence

Expert positions are dated context—not scientific evidence. They never raise the evidence status or become consensus by repetition.

No direct, source-verified endorsement is currently recorded. Research authorship or discussion alone is not treated as endorsement.