Magnesium supplements: Essential boost or over-hyped?

Magnesium is an essential mineral that plays an important role in many of the body’s everyday functions. In fact, the human body contains around 25g of magnesium, and the mineral is involved in more than 300 enzymatic reactions. These processes include energy production, protein synthesis, muscle and nerve function, blood glucose regulation, and blood pressure regulation.¹

So, magnesium is clearly important. But does that mean everyone needs to take a magnesium supplement?

Not necessarily.

Whilst deficiencies can have serious health consequences, excessive or unnecessary supplementation can also lead to unwanted side effects.

What happens if you take too much magnesium?

Magnesium from food is generally considered safe because healthy kidneys can remove excess magnesium from the body. The situation is different with high doses of magnesium from supplements or medicines such as some antacids and laxatives.

Too much supplemental magnesium can cause diarrhoea, nausea, and abdominal cramping. Very high amounts can cause more serious problems, including low blood pressure, muscle weakness, difficulty breathing, and abnormal heart rhythms, with the risk of magnesium toxicity being greater in people with impaired kidney function.²

This is why more magnesium isn’t necessarily better.

Understanding the different types of magnesium

Your body uses many different forms of magnesium, so it’s important to understand how each works, and if it may or may not be beneficial for you in a direct supplement.³

Here are some of the most common forms you’ll come across:

Magnesium glycinate – This chelated form of magnesium is bound to glycine, an amino acid. It is highly absorbable and gentle on the stomach. It’s often used for relaxation, sleep, and to reduce anxiety due to its calming effects on the nervous system.
Magnesium citrate – This is a combination of magnesium and citric acid. It is easily absorbed and supports normal bowel movements, helping relieve constipation. It also helps maintain general magnesium levels, maintaining muscle and nerve function.
Magnesium oxide – This form contains a high amount of elemental magnesium but is less bioavailable compared to others. It can be used for heartburn, indigestion, and constipation due to its laxative properties. However, its lower absorption rate makes it ineffective for helping with magnesium deficiency.
Magnesium malate – Magnesium malate combines magnesium and malic acid, which is involved in energy production in cells. This form is great for reducing muscle pain, fatigue, and supporting energy levels.
Magnesium L-threonate – This form of magnesium is bound to threonic acid, which allows it to cross the blood-brain barrier effectively. It has the potential to enhance cognitive function, and memory.

Magnesium-rich foods: the natural way to get more

Before reaching for a magnesium supplement, it’s worth looking at your diet.

Good dietary sources of magnesium include leafy green vegetables, nuts, seeds, whole grains and legumes. Magnesium is also found in a variety of other foods, with the amount varying between different foods and serving sizes.⁴

Some easy ways to increase your dietary magnesium intake include:

Leafy greens, such as spinach, kale and collard greens
Nuts and seeds, including almonds, cashews, pumpkin seeds and sesame seeds
Whole grains, such as oats, quinoa and barley
Legumes, including black beans, chickpeas and lentils
Fish, including some oily fish such as salmon and mackerel

Eating a varied diet doesn’t just help you get more magnesium. It also provides a range of other vitamins, minerals, fibre and other nutrients that contribute to overall health. And how you prepare foods is also important. For example, steaming or lightly sautéing vegetables can help keep their magnesium content.⁵

If you’re looking for more ways to improve your eating habits, take a look at our tips for transforming your diet.

How much magnesium do you need?

Your magnesium requirements depend on factors including your age and gender. For adults, recommended daily intakes are generally around 270–300mg per day in the UK, depending on gender.

Importantly, these recommendations refer to magnesium from your overall diet, rather than meaning that you need to take the same amount in supplement form.

In the UK, the NHS advises that most people should be able to get all the magnesium they need from a varied and balanced diet.⁶

Do you have a magnesium deficiency?

A genuine magnesium deficiency isn’t particularly common in otherwise healthy people eating a varied diet. However, magnesium deficiency can occur, particularly in certain circumstances.

Early signs can include loss of appetite, nausea, vomiting, fatigue and weakness. More severe deficiency can cause muscle contractions and cramps, numbness, seizures and abnormal heart rhythms.⁷

It’s important not to assume that symptoms like tiredness or muscle cramps automatically mean you have low magnesium, as these symptoms can have many possible causes.

If you’re concerned about your magnesium intake or think you may have a deficiency, speak to your GP or another qualified healthcare professional.

You can also read our guide to whether you’re getting enough magnesium.

So, do you need a magnesium supplement?

For many people, the answer may be no. If you’re eating a varied diet containing plenty of leafy greens, nuts, seeds, whole grains and legumes, you may already be getting enough magnesium.

A magnesium supplement may be useful when dietary intake is inadequate or when a healthcare professional recommends supplementation. However, choosing a supplement isn’t simply about finding the product with the highest dose.

Consider the form of magnesium, the amount of elemental magnesium provided and your individual circumstances.

It’s also important to check with your GP or pharmacist before taking a magnesium supplement if you take medication or have a medical condition, particularly kidney problems. Magnesium can interact with some medicines, including certain antibiotics and medicines used to treat osteoporosis.⁸

The bottom line

Magnesium is an essential mineral, but more isn’t always better.

For most people, getting magnesium through a varied, balanced diet is a sensible place to start. If you do need a supplement, understanding the different types of magnesium and choosing an appropriate dose can help you make a more informed decision.

Ultimately, the best approach is to consider your diet, your individual needs and professional medical advice rather than assuming that everyone needs a magnesium supplement.

Read our articles about magnesium here.

Any questions? Contact one of our Nutritional Therapists via live chat, weekdays from 8 am to 8 pm.