Taking too much magnesium? 7 side effects to watch out for

Want to prevent cramps, maintain nerve function, strengthen your bones and keep your heart healthy? Then make sure to meet your daily magnesium requirements. This mineral is important for your body, as it plays a key role in maintaining your overall health. So, have leafy green vegetables, nuts and seeds, legumes and whole grains. There are also supplements to help you out. But don’t just buy them from a store without consulting a doctor. It is important to know the right dose, as overdose can lead to health issues. Here are some of the magnesium side effects to be aware of.

What are the magnesium benefits?

Before learning about magnesium side effects, let’s find out why it is good for you:

• Supports heart health: It helps maintain a steady heartbeat by regulating muscle contractions, including the heart muscle. It also helps relax blood vessels, reducing blood pressure and lowering the risk of stroke and heart disease. A study, published in Nutrients, found that higher magnesium intake, either dietary or through supplements, helped in protecting against major cardiovascular risk factors, including type 2 diabetes and hypertension.
• Strengthens bones: A major portion of the body’s magnesium is stored in the bones, so it plays a key role in bone formation. “It enhances calcium absorption, and helps prevent conditions like osteoporosis, especially in older people and postmenopausal women,” says nutritionist Falak Hanif.
• Reduces muscle cramps: This mineral helps muscles relax after contracting, preventing cramps and stiffness. It is especially beneficial for fitness enthusiasts, athletes and pregnant women.
• Improves sleep quality: It regulates neurotransmitters and melatonin, both of which are important for a good night’s sleep. “It activates Gamma-aminobutyric acid (GABA), a calming brain chemical, and this helps in falling asleep faster,” says the expert.
• Relieves menstrual discomfort: It reduces bloating, breast tenderness, mood changes, and cramps during menstruation by regulating hormone levels and calming nerve activity.
• Aids digestion: This essential nutrient draws water into the intestines and helps relax the gut muscles, which helps in promoting regular bowel movements. “It acts as a natural laxative when taken in specific forms like magnesium citrate,” shares the expert.

Magnesium overdose

The dosage depends on a person’s age, gender, health status, and purpose of treatment. According to the US National Institutes Of Health, the Recommended Dietary Allowances for this mineral are:

• Birth to 6 months : 30 mg
• 7 to 12 months : 75 mg
• 19–30 years: 400 mg (men), and 310 mg (women)
• 31–50 years: 420 mg (men), and 320 mg (women)

Stay within these limits otherwise there can be a magnesium overdose, which may result from taking too much of a supplement or medicine consisting of the mineral. Sometimes, people with kidney disease or impaired kidney function may also experience magnesium overdose. “The kidneys are responsible for flushing out extra magnesium. In kidney dysfunction, the clearance of this mineral slows down, leading to dangerous buildup,” says the expert.

Magnesium side effects

Generally there are no magnesium side effects if you go for natural food sources. “The body has a natural way of regulating magnesium levels, and any excess magnesium from food is usually excreted through the kidneys via urine,” explains Hanif.

Here are magnesium side effects:

These magnesium side effects are typically seen when the mineral is taken in high doses or poorly absorbed forms, particularly from supplements or intravenous sources.

1. Diarrhea

Too much consumption of magnesium can lead to loose stools. During a study, published in The New England Journal Of Medicine, its excessive consumption was seen as an important cause of chronic diarrhea in 15 of the 359 participants. “The mineral draws water into the intestines, acting as an osmotic laxative. Diarrhea is most likely caused by magnesium citrate, magnesium oxide and magnesium hydroxide,” says the expert.

2. Nausea

One of the magnesium side effects is that the supplements can irritate the stomach lining, especially when taken on an empty stomach. Nausea is most likely caused by high-dose magnesium supplements (any form, especially poorly absorbed ones like oxide).

3. Abdominal cramps

Due to the laxative effect or sensitivity to certain forms, you may have abdominal cramps, one of the common magnesium side effects. “The cramps are most likely caused by magnesium sulfate and magnesium citrate,” says the expert. You may also experience gas and bloating with the cramps.

4. Low blood pressure

Low blood pressure or hypotension can happen due to IV magnesium or taking very high doses of the supplement, as they can relax the blood vessels too much. You may experience dizziness, fainting, blurred vision and feel really tired.

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5. Irregular heartbeat

Irregular heartbeat or arrhythmia is one of the magnesium side effects. “Extremely high magnesium levels affect the heart’s electrical activity. It can lead to skipped beats, slow heart rate or fluttering sensation,” says the expert. It’s mostly caused by excess IV magnesium.

6. Muscle weakness

This mineral affects muscle and nerve conduction; and too much of it can impair function. You will feel sluggishness, fatigue, and have difficulty moving your legs and arms. Muscle weakness may happen if you take IV magnesium in high doses.

7. Breathing difficulty

“Very high magnesium levels can suppress the central nervous system and affect the breathing muscles,” says the expert. You may experience slow or shallow breathing, find it hard to move, and in rare cases, go into coma. This may happen due to excessive intake of IV magnesium or accidental overdose.

It is good to have magnesium-rich foods like spinach, almonds, peanuts and soy milk. However, while taking the supplements, you need to be cautious, as there are magnesium side effects.

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