9 Magnesium Deficiency Symptoms

You’ll 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

But what if you’re deficient? If you suspect you might be or just want to be informed, we’ve listed the most common symptoms of magnesium deficiency and some potential causes for men and women in this guide.

Skip to:

• Common signs
• Causes
• Signs in women
• What you can do

Do you have a magnesium deficiency?

While a true deficiency is rare, many people in the UK have low levels of magnesium, particularly young women.²

Diet is a common cause, especially if you’re not eating enough magnesium-rich foods and you’re consuming lots of processed foods, like white flour which has often had its 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.³

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

What are the most common magnesium deficiency symptoms?

So, what should you look out for? Here are some of the key signs of magnesium deficiency:⁴

1. Muscle cramps and twitches

One of the most common symptoms of low magnesium levels is frequent muscle cramping or twitches. In particularly bad cases, you may experience convulsions or even seizures.⁵

This is thought to be caused by a larger flow of calcium being pumped into your nerve cells, which then hyperstimulates the muscle nerves causing your muscles to twitch or cramp up.⁶

2. Mental health concerns

There is also a link between low magnesium levels and your mental health. In fact, one scientific review from 2015 on over 19,000 patients found that there was an association with depression and hypomagnesaemia.⁷

Scientists have also highlighted that mild anxiety may also be a sign of magnesium deficiency, so this may be something to look into if you’ve noticed you’re feeling more anxious than usual.⁸

3. Weakened bones

Weak bones and increased fractures are common indicators of osteoporosis. But did you know that your magnesium levels may have an impact? Research has shown that good magnesium levels are crucial for bone health, as being deficient in it can contribute to osteoporosis.⁹

4. Muscle weakness

As with your bones, if you’re deficient in magnesium you may experience weakened muscles too. This is thought to be due to the dip in potassium in your muscle cells which happens as a result of low magnesium levels.¹⁰

5. Raised blood pressure

While more studies are needed to understand the depth of this link, scientific reviews have highlighted that magnesium supplementation may help to lower blood pressure in people who already have high blood pressure.¹⁰ Equally, some animal studies have found that magnesium deficiency increased and promoted blood pressure levels.¹¹

6. Irregular heartbeats

Otherwise known as arrythmia, another magnesium deficiency symptom is irregular heartbeats. This could show up as skipped heartbeats, or heart palpitations, which is when there are pauses between each heartbeat.¹² This can also have a knock-on effect, causing dizziness, fainting or shortness of breath.¹³

This symptom of magnesium deficiency is believed to be down to imbalanced potassium levels in and around the heart.^14,15

7. Asthma

Scientists have also discovered a connection between magnesium deficiency and people with asthma. Researchers have found that low magnesium levels seem to be more common in people with asthma, than in those who don’t have it.^16,17

A possible explanation for this is that magnesium deficiency causes calcium to clog lung airways, which makes it harder to breathe.¹⁸ This is why patients are sometimes provided with an inhaler that contains magnesium to help relax their airways.¹⁹

8. Stomach issues

Nausea, vomiting, and diarrhoea are all potential stomach issues that you might experience if you’re low in magnesium.^20,4 Although these symptoms can occur for a variety of reasons, it may be worth getting your magnesium levels checked to see if this is the cause.

9. Reduced appetite

Another reported symptom of magnesium deficiency is a loss of appetite. So, if you’re experiencing this as well as some of the other symptoms we’ve listed, it may be beneficial to get your magnesium levels tested.⁴

Causes of low levels of magnesium in women

If you’re a woman experiencing low magnesium symptoms, you might be wondering what’s causing it.

One study on the effect of magnesium supplementation on women's health and well-being from 2021 stated that common causes include:²¹

• Obesity
• PCOS (polycystic ovary syndrome)
• Type 2 diabetes
• Inflammation
• Inadequate intake
• Pregnancy
• High physical activity
• Excessive sweating

Causes of low levels of magnesium in men

While there aren’t many key causes of magnesium in men alone, here are some potential causes of magnesium deficiency according to the NHS:²²

• Diarrhoea and vomiting
• Malabsorption Medications (e.g., PPIs, laxatives)
• Gastrointestinal fistulae
• Intestinal resection/Short bowel syndrome
• Malnutrition/dietary deficiency (uncommon)
• Medications (e.g., thiazide or loop diuretics, amphotericin, aminoglycosides,
• immunosuppressants, cisplatin, cyclosporin, tacrolimus)
• Diabetes Mellitus/Glycosuria (osmotic diuresis)
• Alcoholism
• Hypercalcaemic states
• Hyperaldosteronism
• Renal tubular disorders
• Inherited disorders e.g., Bartter’s, Gitelman’s syndrome
• Post renal transplant
• Dialysis

Signs of lack of magnesium in women

Aside from the symptoms we mentioned above, are there any signs of magnesium deficiency that only women experience?

Well, research has found that people who regularly experience PMS symptoms generally have low levels of magnesium in their red blood cells.²³

What to do about low magnesium levels

If you suspect that you are low in magnesium, it’s best to get yourself checked by a healthcare professional who can do a blood test to find out more.

If you’re severely deficient, they will decide the best approach. However, if you are mildly deficient (which often means you experience no symptoms) they might recommend taking magnesium supplements to increase your levels and try to keep deficiency at bay.²⁴

One of the best magnesium supplements is magnesium glycinate, which you can find out more about in our article on the benefits of magnesium glycinate.

The final say

Remember, true magnesium deficiency is rare.

A lot of the symptoms we’ve listed are in extreme cases of low magnesium, so you might be mildly deficient with a few or no signs.

Either way, if you’re curious about your magnesium levels, get in contact with your doctor so they can assess you and provide you with personalised advice.

The advice in this article is for information only and should not replace medical care. Please check with your GP or healthcare professional before trying any supplements or remedies. Food supplements must not be used as a substitute for a varied and balanced diet and a healthy lifestyle.