Magnesium chloride is a bioavailable form of magnesium that supports many essential body functions. When someone is deficient, supplementing can improve muscle and nerve function, help regulate blood sugar and blood pressure, assist with bone health, and possibly reduce cardiac rhythm problems. There’s also some evidence that it helps anxiety symptoms, improves sleep quality, and may reduce the frequency and severity of migraines. Animal studies suggest magnesium chloride (and other magnesium salts) may also help in mood regulation and memory, although in humans the data are less definitive.
However, risks exist—especially when consuming high doses or in certain conditions. Gastrointestinal side effects (diarrhea, nausea, abdominal cramps) are among the most common. More serious consequences can occur with excessive intake: low blood pressure, irregular heartbeat, confusion, muscle weakness, and even respiratory depression in severe cases. People with impaired kidney function are especially at risk, since they may not be able to clear high levels of magnesium. Also, magnesium supplements can interact with various medications (blood pressure meds, certain antibiotics, etc.), so medical oversight is crucial.
In practice, to use magnesium chloride safely: start with moderate doses (preferably getting much magnesium from food), avoid going over established supplement upper limits (often around 350 mg/day from non‑food sources unless prescribed). Taking the supplement with food can reduce stomach upset. Those with chronic health issues (kidney, heart, liver), pregnant or nursing, or taking interacting medications should talk to a healthcare provider before starting. With prudent use, magnesium chloride can offer real health benefits without undue risk.