When you hear magnesium supplements, a mineral essential for over 300 enzyme reactions in the body, including muscle contraction, nerve signaling, and energy production. Also known as magnesium citrate, magnesium glycinate, or just plain magnesium, it’s one of the most common supplements people take—not because it’s trendy, but because so many are actually low in it. You don’t need a lab test to suspect you’re deficient. If you get leg cramps at night, feel anxious for no reason, or have trouble falling asleep, your body might be asking for more magnesium.
Not all magnesium supplements are the same. magnesium citrate, a form often used for constipation because it draws water into the intestines might give you diarrhea if you don’t need it. magnesium glycinate, a gentler form bound to the amino acid glycine, is better for sleep and anxiety without the digestive side effects. Then there’s magnesium oxide, a cheap, poorly absorbed form that’s mostly useless unless you’re using it short-term for constipation. The right type matters as much as the dose.
People who take proton pump inhibitors for heartburn, have type 2 diabetes, or drink alcohol regularly are more likely to be low in magnesium. Even stress and intense workouts can drain your stores. But here’s the catch: taking more doesn’t always mean better. Too much can cause nausea, low blood pressure, or worse—irregular heartbeat. The upper limit for supplements is 350 mg per day from pills, not food. Most people get enough from spinach, nuts, beans, and whole grains. Supplements are for filling gaps, not replacing meals.
If you’re thinking about starting magnesium, ask yourself: Are you trying to fix cramps? Improve sleep? Reduce stress? Pick the form that matches your goal. Don’t just grab the cheapest bottle. And if you’re on antibiotics, osteoporosis meds, or blood pressure drugs, check with a doctor first—magnesium can interact.
Below, you’ll find real-world comparisons of magnesium with other supplements, what studies actually show about its effects on sleep and muscle recovery, and how it stacks up against prescription options for conditions like migraines and PMS. No fluff. Just what works, what doesn’t, and what to avoid.
Magnesium supplements can block thyroid medication and certain antibiotics if taken together. Learn the exact timing rules to avoid reduced absorption, stabilize your TSH levels, and keep your meds working properly.
