Magnesium is a mineral that plays a vital role in many functions of the body, such as regulating blood pressure, blood sugar, muscle and nerve activity, and protein synthesis. It is also involved in the production of energy, DNA, and bone health. Magnesium is found in various foods, especially plant-based sources like legumes, nuts, seeds, whole grains, and leafy green vegetables. However, many people do not get enough magnesium from their diet, which can lead to deficiency and increased risk of various health problems, including high blood pressure, heart disease, diabetes, and insomnia.
Magnesium and Blood Pressure
High blood pressure, or hypertension, is a condition where the force of blood against the walls of the arteries is too high. This can damage the blood vessels and increase the risk of heart attack, stroke, kidney disease, and other complications. High blood pressure can be caused by many factors, such as genetics, age, obesity, stress, smoking, alcohol, salt intake, and lack of physical activity. However, some studies have suggested that magnesium deficiency may also contribute to high blood pressure, as magnesium helps relax the blood vessels and improve blood flow.
According to a review of 34 studies, taking magnesium supplements can significantly lower blood pressure, especially in people who have low magnesium levels or high blood pressure. The review found that taking around 350 mg of magnesium per day for an average of 3 months reduced systolic blood pressure (the top number) by 2 mm Hg and diastolic blood pressure (the bottom number) by 1.78 mm Hg.
Another review of 49 studies found that magnesium supplements of 600 mg per day or more were needed to lower blood pressure in people with untreated hypertension, while lower doses were effective in people with uncontrolled hypertension. However, the effects of magnesium on blood pressure may vary depending on the individual, the type and dose of magnesium, and the duration of treatment.
Natural Sources of Magnesium
The best way to get enough magnesium is to eat a balanced diet that includes a variety of magnesium-rich foods. Some of the foods that are high in magnesium are:
Dark chocolate: 1 ounce (28 g) provides 15% of the daily value (DV) for magnesium
Avocados: 1 medium avocado provides 14% of the DV for magnesium
Nuts: 1 ounce (28 g) of almonds, cashews, or Brazil nuts provides 15–20% of the DV for magnesium
Seeds: 1 ounce (28 g) of flaxseed, chia seed, or pumpkin seed provides 25–40% of the DV for magnesium
Legumes: 1/2 cup (86 g) of cooked black beans, edamame, or lima beans provides 10–15% of the DV for magnesium
Whole grains: 1/2 cup (92 g) of cooked quinoa or 1 cup (55 g) of shredded wheat cereal provides 15% of the DV for magnesium
Leafy greens: 1 cup (30 g) of raw spinach provides 6% of the DV for magnesium
Magnesium Supplements and Side Effects
If you have trouble meeting your magnesium needs through food, you may consider taking a magnesium supplement. However, you should consult your doctor before taking any supplement, as magnesium can interact with some medications and health conditions. For example, people with kidney problems, heart block, or myasthenia gravis should avoid taking magnesium supplements, as they can worsen their symptoms or cause complications.
The recommended dietary allowance (RDA) for magnesium for adults is 310–420 mg per day, depending on age and sex. However, some people may need higher doses to correct a deficiency or lower blood pressure. The upper limit (UL) for magnesium from supplements is 350 mg per day, as higher doses can cause side effects.
The most common side effects of taking magnesium supplements are gastrointestinal problems, such as diarrhea, nausea, cramping, or vomiting. These side effects are usually mild and can be avoided by taking lower doses, dividing the doses throughout the day, or taking the supplement with food. However, very high doses of magnesium can cause more serious side effects, such as low blood pressure, irregular heartbeat, confusion, drowsiness, weakness, difficulty breathing, or coma. In rare cases, magnesium overdose can lead to death.
Closing Thoughts
Magnesium is an essential mineral that can help lower blood pressure and prevent or treat various health problems. However, many people do not get enough magnesium from their diet, which can lead to deficiency and an increased risk of hypertension. Taking magnesium supplements can be a safe and effective way to improve magnesium levels and blood pressure, as long as the dose is appropriate and the supplement is taken under medical supervision. However, the best way to get enough magnesium is to eat a balanced diet that includes a variety of magnesium-rich foods, such as legumes, nuts, seeds, whole grains, and leafy greens.
FAQs
Q: How much magnesium should I take to lower my blood pressure?
A: The amount of magnesium needed to lower blood pressure may vary depending on the individual, the type and dose of magnesium, and the duration of treatment.
Some studies have suggested that taking around 350 mg of magnesium per day for an average of 3 months can reduce blood pressure, while others have found that higher doses of 600 mg per day or more are needed, especially for people with untreated hypertension. However, the upper limit for magnesium from supplements is 350 mg per day, as higher doses can cause side effects. Therefore, it is advisable to consult your doctor before taking any magnesium supplement.
Q: What are the best food sources of magnesium?
A: The best way to get enough magnesium is to eat a balanced diet that includes a variety of magnesium-rich foods, such as legumes, nuts, seeds, whole grains, and leafy green vegetables. Some of the foods that are high in magnesium are:
– Dark chocolate: 1 ounce (28 g) provides 15% of the daily value (DV) for magnesium
– Avocados: 1 medium avocado provides 14% of the DV for magnesium
– Nuts: 1 ounce (28 g) of almonds, cashews, or Brazil nuts provides 15–20% of the DV for magnesium
– Seeds: 1 ounce (28 g) of flaxseed, chia seed, or pumpkin seed provides 25–40% of the DV for magnesium
– Legumes: 1/2 cup (86 g) of cooked black beans, edamame, or lima beans provides 10–15% of the DV for magnesium
– Whole grains: 1/2 cup (92 g) of cooked quinoa or 1 cup (55 g) of shredded wheat cereal provides 15% of the DV for magnesium
– Leafy greens: 1 cup (30 g) of raw spinach provides 6% of the DV for magnesium.
Q: What are the side effects of taking magnesium supplements?
A: The most common side effects of taking magnesium supplements are gastrointestinal problems, such as diarrhea, nausea, cramping, or vomiting. These side effects are usually mild and can be avoided by taking lower doses, dividing the doses throughout the day, or taking the supplement with food. However, very high doses of magnesium can cause more serious side effects, such as low blood pressure, irregular heartbeat, confusion, drowsiness, weakness, difficulty breathing, or coma. In rare cases, magnesium overdose can lead to death. Therefore, it is important to follow the recommended dosage and consult your doctor before taking any magnesium supplement.
Q: How does magnesium lower blood pressure?
A: Magnesium is believed to lower blood pressure by relaxing the blood vessels and improving blood flow. Magnesium also works as an antioxidant to counteract blood vessel damage and inflammation, which can contribute to high blood pressure. Additionally, magnesium helps regulate other minerals and hormones that affect blood pressure, such as calcium, potassium, sodium, and renin-angiotensin-aldosterone system.
Q: Who should avoid taking magnesium supplements?
A: Magnesium supplements are generally safe for most people, but some people should avoid taking them or use them with caution. These include people with kidney problems, heart block, or myasthenia gravis, as magnesium can worsen their symptoms or cause complications. Magnesium can also interact with some medications, such as antibiotics, diuretics, bisphosphonates, and blood pressure drugs, and affect their absorption or effectiveness. Therefore, it is advisable to check with your doctor before taking any magnesium supplement if you have any medical condition or take any medication.
