Magnesium on its own has not been shown to help with leg cramps, according to clinical research. However, studies have shown that it plays a major role in both muscle and bone health, and scientists have found many associations and overlap between people who may have leg cramps and those who consume less or have lower levels of magnesium.
Here’s what we know:
It’s possible that magnesium supplement benefits only show up after taking it for longer periods, such as 60 days compared to only 4 weeks, but larger, randomized trials need to be done to understand why some studies show benefits for leg cramps and some do not.
There is no recommended amount of magnesium for leg cramps, since it’s not definitely known to help. But a goal to consume adequate amounts of magnesium is important for overall well-being.
The Recommended Dietary Allowance (RDA) for magnesium varies based on certain factors:
The tolerable upper intake level (UL) for magnesium that comes from supplement sources is 350 mg for adults of all ages.
Leg cramps are a common complaint of many people. They can happen at almost any age, for different reasons. Sometimes the cause is not known. Some people may be more likely to experience them than others.
Some common triggers of leg cramps include:
If you are experiencing leg cramps consider talking to your doctor in order to address the underlying cause or contributing factors.
Magnesium can be found in many foods. Eating a diet that is rich in magnesium and other essential nutrients is the best way to support overall health. Foods that contain higher amounts of magnesium include:
Many other foods contain smaller amounts of magnesium, including edamame, baked potatoes, brown rice, yogurt, oatmeal, other breakfast cereals, kidney beans, banana, and salmon.
Around 30-40% of the magnesium that you eat from food is absorbed. If you do not eat enough dietary magnesium, supplements can help to fill in nutritional gaps. Magnesium is often included in multivitamins and prenatal supplements. The Care/of Prenatal Vitamin includes 100 mg of magnesium hydroxide sourced from sea water, while the Care/of Multivitamin contains 90 mg. The Care/of Magnesium supplement provides 200 mg.
Because magnesium is not directly known to address leg cramps, there is no specific form that is recommended.
There are many forms of magnesium supplements available. Some common types of magnesium include:
Magnesium hydroxide is the form used in Care/of supplements. Research has noted that this is a clinically relevant form with no severe side effects noted. Magnesium citrate is also commonly used.
Magnesium works with other nutrients in the body to support essential functions and overall health.
Calcium is widely known to be a major component of bones and teeth. Magnesium is also found in the bones. A deficiency in any bone-related nutrient affects overall health—for example, a diet that contains plenty of calcium but little magnesium could still result in overall challenges with bone strength. Magnesium is also needed to help transport calcium ions across cell membranes, which supports healthy nerve impulses and muscle function.
You need calcium and magnesium to be balanced, which generally means about a 2-to-1 ratio. When your diet is low in calcium and you eat more magnesium, or take magnesium supplements, the effect can further reduce how much calcium is absorbed from the foods that you do eat.
Both magnesium and potassium are needed for health, especially as electrolytes that help to regulate fluid balance inside and outside of cells. Electrolyte nutrients are also important for healthy muscle function, including the heart.
Magnesium and potassium are needed in balanced amounts. One can’t replace the other. Beyond that, low levels of one can also negatively affect the other. For example, not consuming enough magnesium increases how much potassium is lost from the body in the urine. Magnesium is also needed to help potassium ions cross cell membranes—this supports healthy muscle contraction, including a normal heart rhythm.
You can find relief from leg cramps with these proven strategies.
The first thing to do if your leg is cramping is to stretch it in an appropriate way. Always do this gently, since sudden movements may worsen muscle discomfort.
Try one of these:
If you are prone to leg cramps, research has found that stretching more frequently may help prevent them, especially if you do it before bed. If stretching does not ease your muscle cramping, see a medical provider.
Massage can help to ease tense muscles, which may help alleviate muscle cramps. You can use your hands to massage the cramped area or consider a foam roller to help relax your leg muscles.
Sometimes leg cramps happen because your body is low on fluids. Dehydration is a common cause. While there’s no universally accepted amount of fluid that everyone has to consume for optimal hydration, if you aren’t consuming between 6-8 glasses of fluids per day, that may be a good place to start. You can also boost your hydration with electrolytes added to your water.
Magnesium may not directly address leg cramps, but it is necessary for healthy muscles. It’s needed to help muscles all through the body, including the heart, contract and relax in normal ways. Magnesium also plays a role in muscle fitness, primarily in people who are low in magnesium, like older adults, those experiencing stress, or people who consume alcohol regularly. In college-aged adults, magnesium helped with muscle soreness, perception of exertion, and recovery after strength training.
Bone health relies on much more than calcium alone. Magnesium is needed to help with calcium transport, and bones also contain magnesium. Adequate magnesium intake is needed to support strong bones and healthy bone density. This is because magnesium plays an important role in stimulating osteoblasts for normal bone formation. Magnesium deficiency interferes with the release of parathyroid hormone, which is a vital regulator of calcium balance within the body.
Some people feel strongly that magnesium supplements help their leg cramps. While scientific evidence from clinical trials has not proven this link, magnesium is essential for healthy muscles and bones. Inadequate intake from diet is common on American adults, and low levels can have a major impact on overall skeletal, muscular, and cellular health. When you’re dealing with leg cramps, stretching or massage are the best things to help in the moment. To support overall muscle health, focus on eating plenty of magnesium-rich foods, and ask your healthcare provider if a dietary supplement would be helpful.