Magnesium is a vital nutrient found in a variety of plant-based and animal foods, but a diet with low amounts of the mineral can lead to a range of immediate symptoms and long-term risks for heart disease, according to a growing body of research.
Magnesium improves bone density, promotes better sleep, increases bowel regularity and lowers the risk and intensity of migraine headaches. The mineral also supports healthy brain function, limiting the risk of anxiety and depression.
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The National Institutes of Health estimates as many as half of Americans consume less than the recommended amount of magnesium, which is about 400-420 milligrams daily for men and 310-320 milligrams for women. Pregnant women are advised to increase their intakes.
Diagnosing magnesium deficiency can be difficult for doctors because it is often a chronic condition that doesn't appear on a typical blood test. The mineral is mostly stored in bones and cells, making it a challenge to catch cases that aren't detectible in blood and other test samples.
In a 2018 study, the NIH called magnesium deficiency a public health crisis and "principal driver of cardiovascular disease," the leading cause of death globally. In a review published this month in the journal Nutrients, researchers evaluated multiple studies that have linked magnesium deficiency to worsening heart health.
The review found that low levels of the mineral consistently have been linked to high blood pressure, stroke, heart failure and abnormal heart rhythm. These effects are thought to result from increased inflammation and oxidative stress, a condition that damages cells and tissues due to an imbalance of antioxidants and free radicals in the body.
Common symptoms of magnesium deficiency include fatigue, muscle weakness and cramps, numbness and tingling, and nausea and vomiting. Low levels of magnesium also can lead to loss of appetite and irregular heartbeat.
The link between magnesium deficiency and cardiovascular disease has received more focus in recent years.
"As late as 2014, The Harvard Medical School’s HEALTHbeat advisory stated that 'Magnesium deficiency is very rare,'" the journal review author said. "It is only in the last 10 years that serious attention has been given to inadequate magnesium status having an impact on the incidence of cardiovascular disease in the general population."
There are a number of dietary steps people can take to boost their magnesium levels.
"Lots of foods you probably already eat are high in magnesium," dietician Karen Z. Berg told Medical News Today. "The best sources of magnesium are dark leafy greens like spinach or Swiss chard, as well as nuts and seeds. Almonds, cashews, pumpkin seeds or chia seeds are all great options. Black beans and edamame are also good sources of this mineral.”
Other good sources of magnesium include poultry, salmon, beef, milk, yogurt and whole grains. Reducing coffee intake also may help improve absorption of the mineral.
Although magnesium supplements are widely available and considered safe, there has been limited research into their benefits for heart health. The NIH said magnesium supplements may decrease blood pressure by a small amount, but more research is needed to understand whether they help protect bones, reduce migraine symptoms or manage blood-sugar and insulin sensitivity in people with Type 2 diabetes.
Berg recommends trying to find ways to incorporate more magnesium-rich foods into a balanced diet.
“It is important for overall health to have enough magnesium in your diet," she said.