Magnesium citrate nonahydrate
Also known as: Magnesium citrate (hydrated form), Magnesium citrate nonahydrate
Overview
Magnesium citrate nonahydrate is a hydrated salt form of magnesium bound to citric acid, commonly used as a dietary supplement to correct magnesium deficiency and as an osmotic laxative. It is naturally derived from magnesium and citric acid, with the nonahydrate indicating nine water molecules associated with the compound. Its primary applications include magnesium supplementation for deficiency, support of neuromuscular function, and cardiovascular health. Magnesium citrate is known for its relatively good bioavailability compared to other magnesium salts. Research on magnesium supplementation is extensive, with numerous randomized controlled trials (RCTs) and meta-analyses addressing its effects on various health outcomes, including depression and inflammation. While specific studies on the nonahydrate form are less common, most research refers broadly to magnesium citrate.
Benefits
Magnesium citrate nonahydrate offers several evidence-based benefits. Magnesium supplementation, including magnesium citrate, significantly reduces depression scores in adults with depressive disorders, showing a moderate to large effect size (SMD of −0.919, 95% CI: −1.443 to −0.396, p=0.001) based on a meta-analysis of 7 RCTs. It also exhibits anti-inflammatory effects, evidenced by a significant reduction in C-reactive protein (CRP) levels, a key biomarker of systemic inflammation, as found in a systematic review and meta-analysis. While potential improvement in oxidative stress markers is less conclusive, magnesium citrate is commonly used to alleviate symptoms of magnesium deficiency such as muscle cramps and fatigue. Adults with depressive disorders and individuals with suboptimal magnesium intake or inflammatory conditions are the primary beneficiaries. Benefits on depression and inflammation are typically observed within 4–12 weeks of consistent supplementation.
How it works
Magnesium acts as a crucial cofactor in over 300 enzymatic reactions, essential for energy metabolism, neurotransmitter synthesis, and muscle contraction. In the brain, it modulates NMDA receptor activity, which is implicated in the pathophysiology of depression. Magnesium citrate nonahydrate provides bioavailable magnesium ions that increase serum and intracellular magnesium levels, thereby influencing nerve conduction, muscle function, and inflammatory pathways. The citrate component is believed to enhance magnesium absorption and bioavailability compared to other magnesium salts. Absorption primarily occurs in the small intestine. The hydration state (nonahydrate) does not significantly alter the absorption mechanism but affects the molecular weight and, consequently, dosing calculations.
Side effects
Magnesium citrate nonahydrate is generally safe when used within recommended doses. The most common side effect, occurring in over 5% of users, is diarrhea and general gastrointestinal discomfort, primarily due to its osmotic laxative effect. Less common side effects (1-5%) include nausea and abdominal cramping. Rare but serious side effects (<1%) include hypermagnesemia, particularly in individuals with renal impairment. Symptoms of hypermagnesemia can include lethargy, muscle weakness, cardiac arrhythmias, and respiratory depression. Caution is advised with concurrent use of other magnesium-containing products, phosphate binders, and medications that affect renal function. Contraindications include severe renal impairment, bowel obstruction, and hypersensitivity to magnesium citrate. Dose adjustment and careful monitoring are critical in patients with renal failure to prevent magnesium toxicity.
Dosage
For general magnesium supplementation, the minimum effective dose is approximately 200 mg of elemental magnesium daily. The optimal dosage range for adults is typically 200–400 mg elemental magnesium daily, often divided into 2–3 doses to improve absorption and minimize gastrointestinal side effects. The maximum safe dose varies by individual and indication; however, doses exceeding 350 mg elemental magnesium daily from supplements may increase the risk of adverse effects in some populations. Magnesium citrate nonahydrate can be taken with or without food. Clinical dosing is usually based on the elemental magnesium content, requiring adjustment for the molecular weight due to its hydration state. Absorption can be reduced by high doses of calcium or phytates in the diet. Vitamin D may enhance magnesium absorption and utilization.
FAQs
Is magnesium citrate nonahydrate safe for daily use?
Yes, it is generally safe for daily use within recommended doses, but caution is advised for individuals with renal impairment due to the risk of magnesium accumulation.
How quickly does it work for depression?
Benefits for depression may become apparent within weeks to months of consistent supplementation, as observed in clinical trials.
Can it cause diarrhea?
Yes, due to its osmotic laxative properties, magnesium citrate can cause diarrhea, especially at higher doses. Dividing doses may help mitigate this.
Is it better than other magnesium forms?
Magnesium citrate generally offers better bioavailability than forms like magnesium oxide or sulfate, but it may cause more gastrointestinal side effects compared to glycinate or malate.
Should it be taken with food?
While not strictly necessary, taking it with food can help reduce potential gastrointestinal discomfort.
Research Sources
- https://pmc.ncbi.nlm.nih.gov/articles/PMC10783196/ – This systematic review and meta-analysis of 7 RCTs involving 325 adults with depressive disorder found that magnesium supplementation significantly reduced depression scores (SMD −0.919, p=0.001), indicating a moderate to large effect. The study highlights magnesium's potential as an adjunctive treatment for depression, despite heterogeneity in depression scales and small sample sizes in some included studies.
- https://pubmed.ncbi.nlm.nih.gov/40563371/ – This systematic review and meta-analysis, encompassing 28 human and animal studies, demonstrated that magnesium supplementation reduced C-reactive protein (CRP) levels, indicating an anti-inflammatory effect. However, it found no conclusive effect on oxidative stress biomarkers. The study's quality was moderate due to mixed human and animal data and variability in biomarkers assessed.
- https://globalrph.com/medcalcs/magnesium-citrate-dosing-calculator/ – This clinical review and dosing guide summarizes recommended adult doses of 200–400 mg elemental magnesium daily for magnesium citrate. It emphasizes caution in patients with renal failure due to the risk of hypermagnesemia and notes common gastrointestinal side effects. This source provides practical, clinically relevant dosing and safety information.