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Why we need magnesium

23 Nov 2022 • 2 min read

You will have heard of magnesium, but you might not realise how crucial it is to your health.

Magnesium is an essential mineral which has several important functions within your body, and keeping adequate levels is vital to the wellbeing of your body and mind.

Your body uses magnesium in over 300 biochemical reactions, and helps build bones, generate energy, keep your nerves functioning, keep your blood sugar steady and fuel electrical activity within the heart and the brain.1

Magnesium is the fourth most abundant mineral in your body. Your body can’t make it, so you must get magnesium through the foods you eat.

Why do we need magnesium?

Here are some of the main reasons why we need magnesium.

To make energy

Magnesium plays an important role in energy metabolism. This is the process where the nutrients from your food are converted into energy to be used by the body.

Magnesium is a key component in the creation of a molecule called adenosine triphosphate (ATP) in your cells, which is responsible for delivering energy to every cell in your body.2 

Without magnesium, this molecule can’t do its job effectively, which is why fatigue and low energy are common side effects of low magnesium levels.

To build strong bones

Magnesium is found mostly in your bones, but also in other tissues such as your muscles and joints. Your bones rely on magnesium to stay strong.

Magnesium is essential for the absorption of calcium, and these two minerals work closely together.

For example, magnesium helps the bones retain their calcium by taking calcium from the bloodstream back into the bones.

A long-term deficiency in magnesium causes loss of bone mineral density, which can lead to bone problems such as osteoporosis.3

To fuel your muscles

Magnesium helps muscle function, too.

To work properly, your muscles are constantly contracting and relaxing, and magnesium is what enables the relaxing of the muscles.

This is why muscle aches, cramps and twitches (such as those irritating eye twitches some of us experience) are a common symptom of a magnesium deficiency.

Following on from this, it’s not difficult to see why magnesium helps prevent constipation, as it helps your digestive muscles and gastrointestinal tract to relax, helping you pass stools more easily.

A study from Japan showed that those with low magnesium intake in their diets tended to suffer from increased levels of constipation.4

Handpicked content: Give your workout a boost with magnesium

To keep your heart beating

As your heart is the most important muscle in the body, it’s no surprise that magnesium is so important to cardiovascular health.

Your heart relies on magnesium to keep its beat strong and regular, and relaxes your arteries allowing your blood to flow easily, which also lowers blood pressure.

Magnesium may also help regulate heart palpitations and that ‘fluttery’ feeling in your chest.

A prominent ongoing heart study from the US reported in 2013 that low magnesium is associated with the development of irregular heartbeat.5

Handpicked content: How magnesium helps your blood pressure

To keep you calm

Keeping your magnesium levels topped up can help calm your nervous system down, reduce feelings of anxiety, beat insomnia and promote better sleep.

It does this by regulating activity of the body’s ‘stress response system.’6 

Magnesium has also been shown to reduce cortisol, which is a hormone released by the body when under stress.7 

According to a 2006 study on university students, stress actually depletes the magnesium levels in your body8 so it’s important to pay attention to your levels if you feel you’re prone to stress.

It has even been linked with helping depression in some small studies,9 although research into this is ongoing.

Handpicked content: How stress snatches magnesium

Might you have a magnesium deficiency?

While a true deficiency is rare, many people in the UK have low levels of magnesium, particularly young women.10 

Diet is mostly to blame, with people not eating enough magnesium-rich foods, and consuming too many processed foods such as white flour which have often had their mineral levels depleted.

Also, fizzy drinks have been strongly linked to lowering magnesium levels thanks to the phosphoric acid they contain. Fizzy drinks, especially colas, have been shown to lower bone mineral density which can eventually lead to osteoporosis.11

Don’t panic, as the harmful effects of low magnesium levels won’t happen overnight.

However, over the years, you might notice a lack of energy, slower muscle repair and weaker bones in later years. This should give you enough reason to start including a wide variety of magnesium-rich foods in your diet today.

You can find magnesium in leafy greens such as spinach, nuts like cashews and almonds, seeds, eggs, and seaweed and kelp.

Choose organic varieties where possible, which are grown in soil which tends to be higher in magnesium.

The NHS recommends 300mg a day for men and 270mg a day for women.12 50g of cashew nuts provides 146mg.

Adding Epsom salts to your bath is another way you can ensure your body is getting enough magnesium, as your skin absorbs the magnesium sulfate from the salts dissolved in warm water, making them ideal for muscle relaxation and recovery after sports.

Last updated: 20 July 2021

Advice is for information only and should not replace medical care. Please check with your GP before trying any remedies.


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