Magnesium is an essential mineral involved in hundreds of chemical reactions in the body. It helps with energy production and metabolism, muscle and nerve function, blood pressure regulation, bone strength, and heart and brain health. Adults generally need about 320 mg (women) to 420 mg (men) of magnesium per day from food and supplements combined, but many people fall short of those levels. Blood tests can give a rough idea of magnesium status, but they do not always reflect total body stores.

What is magnesium citrate?

Magnesium citrate is one of several forms of supplemental magnesium. It’s a salt in which magnesium is combined with citric acid. It’s widely used because it is relatively well absorbed and tends to be affordable. At higher doses magnesium citrate can act as an osmotic laxative (it draws water into the gut), which is why it’s sometimes used to relieve constipation or prepare the bowel before procedures.

How it compares with other magnesium forms

Not all magnesium supplements are the same. They differ in how well the magnesium is absorbed and how likely they are to cause gastrointestinal effects like loose stools.

• Magnesium citrate: Good absorption and good value. Effective for raising magnesium intake, but higher doses commonly cause loose stools or diarrhea.

• Magnesium bisglycinate (glycinate) and magnesium chloride: Well absorbed and usually gentler on the gut, with less risk of diarrhea—good choices if you want to increase stores without laxative effects.

• Magnesium oxide: Inexpensive but less well absorbed and more likely to cause stomach upset and diarrhea for some people.

• Magnesium gluconate, lactate, aspartate: Generally well absorbed but can cause diarrhea at higher doses.

• Magnesium L‑threonate: More expensive, usually provides lower elemental magnesium per dose, but can cross into the brain and is chosen by some for cognitive or sleep-related goals. It’s less efficient for restoring overall body magnesium stores.

Benefits people seek from magnesium

When magnesium intake is adequate, people may see benefits in several areas:

• Blood pressure and cardiovascular health: Magnesium supports healthy blood pressure regulation and heart function.

• Blood glucose management: Adequate magnesium helps with insulin sensitivity and glucose control.

• Bone health: Magnesium is a component of bone and supports bone strength.

• Muscle and nervous system symptoms: Magnesium can reduce muscle cramps, ease menstrual-related discomfort, and help with certain types of headaches.

• Sleep and cognition: Certain forms (e.g., L‑threonate) are chosen for potential effects on sleep and cognitive function, though formulations and doses differ.

Guidance for using magnesium citrate

• Aim for a realistic total intake: If your diet is already plant‑rich, lower supplement doses (around 300–350 mg of elemental magnesium daily from food plus supplement combined) are often sufficient. Keep in mind the recommended dietary allowances: about 320 mg for adult women and 420 mg for adult men.

• Check the label for elemental magnesium: Supplement labels list the total compound weight and the amount of elemental magnesium—the part your body actually uses. Compare products on elemental magnesium rather than tablet weight.

• Start low and adjust: If you try magnesium citrate, begin with a lower dose and increase gradually as needed. If you develop loose stools or cramping, reduce the dose or switch to a gentler form (bisglycinate or chloride).

• Timing: Some people prefer taking magnesium in the evening because it can be relaxing; others split the dose morning and evening to reduce GI effects. Taking magnesium with food may decrease stomach upset.

• Drug interactions and health considerations: Magnesium can interact with certain medications (for example some antibiotics, osteoporosis drugs, and thyroid medications), and it is cleared by the kidneys. If you have kidney disease, are pregnant or breastfeeding, or take prescription medications, discuss magnesium supplementation with a healthcare professional before starting.

Side effects and safety

The most common side effect of magnesium citrate is diarrhea or loose stools, especially at higher doses. Stomach cramping can also occur. Serious problems from magnesium supplements are uncommon in people with normal kidney function, but excessive intake can lead to symptoms such as low blood pressure, weakness, slowed breathing, or heart rhythm changes—this is more likely in people with impaired kidney function. If you experience concerning symptoms, stop the supplement and seek medical advice.

Recommended products

Look for reputable brands and third‑party testing to ensure product quality and accurate labeling. Examples of commonly recommended, third‑party tested options include magnesium glycinate (glycinate is the salt name) and chloride formulations as gentler choices, and magnesium citrate for good value. Examples of third‑party tested products include NOW Magnesium Glycinate, InnovixLabs Advanced Magnesium, Nutricology Magnesium Chloride Liquid, and SlowMag—these are examples of the kinds of products people choose when quality is a priority.

Conclusion

Magnesium citrate is a well‑absorbed, cost‑effective form of magnesium that can help raise intake and support heart, bone, metabolic, and muscle health. Its main downside is a higher chance of loose stools at larger doses. If you want to supplement a balanced, plant‑rich diet, start with a modest dose (often in the 300–350 mg total magnesium range when combined with dietary intake), monitor how you feel, and consider gentler forms like magnesium bisglycinate or chloride if gastrointestinal side effects occur. If you have kidney problems, take prescription medications, or are pregnant or breastfeeding, discuss supplementation with your healthcare provider.

Join Mito Health’s annual membership to test 100+ biomarkers with concierge-level support from your care team.