Magnesium is an essential mineral that has numerous functions in the human body. People who do not get enough of this nutrient may experience various symptoms, including muscle cramps.
Muscle cramps, especially leg cramps, are a common issue. They can occur for many different reasons apart from magnesium deficiency. However, some companies are marketing the mineral as a possible solution. So, does it really work?
We look at the current evidence on magnesium for leg cramps and discuss whether it is an effective remedy.
Magnesium for Cramps
Magnesium is a mineral that occurs naturally in many foods. It is a vital component of a healthy diet, and it has many important functions in the body, including:
- Regulating muscle and nerve function
- Maintaining a regular heartbeat
- Controlling blood sugar and blood pressure
- Aiding protein, bone, and DNA synthesis
People who do not consume enough magnesium may develop a deficiency. This is especially common in older adults. Other factors that can increase the risk of magnesium deficiency include:
- Alcohol abuse
- Conditions that affect nutrient absorption, such as celiac or Crohn’s disease
- Type 2 diabetes
The symptoms of magnesium deficiency can affect the entire body. Some of the most common examples include:
- Reduced appetite
- Nausea or vomiting
Severe deficiencies may cause:
- Muscle cramps
- Mood changes
- Skin numbness or tingling
- Abnormal heart rate
Because muscle cramps are sometimes a symptom of magnesium deficiency, some people assume that magnesium supplements may help. However, this is not necessarily true. In fact, research suggests that supplementation has little benefit for people with leg cramps.
Research on Magnesium and Leg Cramps
A 2012 review of seven trials and 406 participants is one example. It included three studies assessing magnesium for muscle cramps in pregnancy and four on cramps with no apparent cause. The researchers looked at various measures, including the number of cramps per week and cramp intensity and duration.
The results of the pregnancy studies were mixed, with just one of three finding magnesium beneficial. However, in the remaining trials, there were no significant differences between magnesium and placebo.
Research shows with “moderate certainty” that magnesium does not reduce cramp severity or frequency in older adults.
A 2020 review had very similar findings. It assessed 11 trials and 708 participants, including older adults, pregnant women, and liver cirrhosis patients.
The researchers concluded that there was “moderate certainty” that magnesium does not reduce cramp severity or frequency in older adults. They also stated that more research is necessary on pregnancy and condition-related cramps, as the existing evidence is low quality.
How Much Magnesium for Leg Cramps?
Since there is currently no evidence to support its use, there is no standard magnesium dose for leg cramps. However, individuals must consume adequate magnesium to meet their dietary needs each day.
The recommended daily allowance (RDA) for adults is 400–420mg for men and 310–320mg for women. The requirements during pregnancy increase slightly to 350–360mg daily.
Magnesium Dosage for Leg Cramps at Night
Leg cramps are common at night and can cause sleep disturbances.
One possible reason that night cramps are so prevalent is that people (especially older adults) may reduce fluid consumption in the evening. Doing this may reduce the need to get up and use the bathroom, but it can also lead to dehydration, another risk factor for muscle cramps.
Unfortunately, there is little evidence that magnesium can help. A 2017 study compared magnesium oxide to a placebo in 94 adults. The magnesium oxide dosage was 865mg (equivalent to 520mg elemental magnesium). The results suggested that magnesium was no better than the placebo for relieving night-time leg cramps.
A 2014 review had slightly more positive results. It included seven trials and 361 participants. The authors concluded that magnesium was probably ineffective for night cramps in the general population. However, it might have a small effect on pregnant women. More research is necessary to confirm these results.
Sources of Magnesium
Although there is no evidence supporting magnesium supplements for leg cramps, it is essential to consume enough of this mineral daily. Some of the best food sources of magnesium include:
- Peas and beans
- Nuts and seeds
- Whole grains
- Leafy greens
- Fortified foods, such as cereal and bread
- Milk, yogurt, and some other dairy products
Anyone who finds it challenging to get enough magnesium from food may wish to try a supplement. However, buyers should note that there are several different types. Magnesium aspartate, citrate, lactate, and chloride are considered the most effective as these forms are easier to absorb.
It is also essential to understand that magnesium supplements can cause several side effects, including diarrhea, nausea, and abdominal pain. Very high doses could lead to complications such as an irregular heartbeat or an increased risk of heart attacks.
Supplements can also interact with certain medicines. Therefore, it is advisable to consult a physician or dietician before use.
Bottom Line on Magnesium for Leg Cramps
Muscle cramps can be a symptom of magnesium deficiency. However, there is currently no scientific evidence supporting the use of magnesium supplements for muscle cramps.
There is currently no scientific evidence supporting the use of magnesium supplements for muscle cramps.
That said, the mineral has many crucial functions in the body, and it is necessary to consume enough each day. The best way to do this is by eating more magnesium-rich foods. Anyone unable to do this may consider supplementation under the guidance of a healthcare professional.