Conclusion: It is unlikely that magnesium supplementation provides clinically meaningful cramp prophylaxis to older adults experiencing skeletal muscle cramps. In contrast, for those experiencing pregnancy-associated rest cramps the literature is conflicting and further research in this population is needed. We found no RCTs evaluating magnesium for exercise-associated muscle cramps or disease-state-associated muscle cramps (for example amyotrophic lateral sclerosis/motor neuron disease) other than a single small (inconclusive) study in people with liver cirrhosis, only some of whom suffered cramps.
PubMed 32956536 ↗Calcium Carbonate
People mainly take Calcium Carbonate for mood. Based on 4 first-hand reports and 60 meta-analyses & systematic reviews in the medical literature. Ranked #435 of 1,974 overall.
Of reports that state an outcome, 67% are positive.
What Calcium Carbonate does, according to users
Of the people who reported each effect, the share who said it got better.
What the research says
Systematic reviews and meta-analyses from PubMed, with their published conclusions.
3+ meta-analyses or systematic reviews and 10+ randomized controlled trials in humans. The grade measures how much human research exists — read the conclusions below for what it found.
Conclusion: Given the very low-certainty evidence, we are unsure whether population-based multicomponent or nutrition and medication interventions are effective at reducing falls and fall-related injuries in older adults. Methodologically robust cluster RCTs with sufficiently large communities and numbers of clusters are needed. Establishing a rate of sampling for population-based studies would help in determining the size of communities to include. Interventions should be described in detail to allow investigation of effectiveness of individual components of multicomponent interventions; using the ProFaN
PubMed 38180112 ↗Conclusion: The phosphate-binding equivalent dose was then defined as the dose of each binder in g × its RPBC, which would be the binding ability of an equivalent weight of calcium carbonate. The phosphate-binding equivalent dose may be useful in comparing changes in phosphate binder prescription over time when multiple binders are being prescribed, when estimating an initial binder prescription, and also in phosphate kinetic modeling.
PubMed 21338393 ↗Conclusion: Current findings suggest that the beneficial effect of Chinese herbal medicines in improving BMD is still uncertain and more rigorous studies are warranted.
PubMed 24599707 ↗Dosage people report
As stated by users — not a recommendation. Follow the label or your doctor.
Reported side effects
How often each side effect came up across all reports.
What users say
Verbatim quotes, shortened only — each links to the original discussion.
“Calcium Carbonate (seems to help too)”
“Just 500mg of Calcium Carbonate makes me feel amazing. It's like I'm high.”
“For me its not euphoric but calcium does help reducing muscle twitches and cramps a lot with my body while magnesium makes it worse.”
Other options for mood
User data from public discussions; research from PubMed. Information only, not medical advice — talk to a doctor before starting, stopping or combining anything. Data updated October 2, 2026. How we rate