Magnesium is one of the hardest-working minerals in the human body. It acts as a cofactor in more than 300 enzyme systems, supporting everything from muscle and nerve function to energy production, blood sugar control and the regulation of blood pressure. It also contributes to the structure of bones and helps the body make protein and DNA. Because it plays such a wide-ranging role, it pays to understand the nutrients your body relies on, and health and wellness brands such as vitabright can be a useful starting point for learning more about everyday nutrition.
In healthy people, a true magnesium deficiency is relatively uncommon, because the kidneys reduce how much magnesium is lost in urine when intake is low. However, a diet consistently short on magnesium-rich foods, certain health conditions, some medications and regular heavy drinking can all lower your levels over time. The early signs are often subtle and easy to mistake for something else, so here are eight to be aware of.
1. Muscle Cramps, Twitches and Spasms
Magnesium helps muscles relax after they contract. When levels fall, nerve and muscle cells can become more excitable, which may lead to cramps, involuntary twitches, spasms or tremors. Occasional cramps are common and usually harmless, but frequent or persistent ones are worth mentioning to your doctor.
2. Fatigue and Weakness
Magnesium is essential for producing ATP, the molecule cells use for energy. Tiredness and muscle weakness are among the early, non-specific signs of low magnesium. Because fatigue has so many possible causes, it is rarely a reason on its own to assume a deficiency, but it can be one piece of the picture.
3. Loss of Appetite, Nausea and Vomiting
A reduced appetite, feeling sick and vomiting are recognised early symptoms of magnesium deficiency. These symptoms overlap with many other conditions, so they are best viewed alongside any other signs on this list.
4. Numbness and Tingling
As levels drop further, some people experience numbness or a pins-and-needles sensation, often in the hands, feet or face. This happens because magnesium plays an important role in how nerves send signals.
5. An Irregular Heartbeat
Magnesium helps maintain a steady heart rhythm. Low levels can contribute to abnormal heart rhythms (arrhythmias), which may feel like palpitations, a fluttering sensation or a skipped beat. Any new or worrying change in your heartbeat should be checked by a medical professional promptly.
6. Changes in Mood or Personality
Magnesium is involved in brain and nervous system function, and personality changes are a recognised symptom of deficiency. Research has also explored links between low magnesium and conditions such as depression and anxiety, although the evidence is still developing and low magnesium is only one of many possible factors.
7. Low Calcium or Potassium Levels
Magnesium deficiency often occurs alongside low blood levels of calcium (hypocalcaemia) and potassium (hypokalaemia), because magnesium helps the body regulate both minerals. This sign is usually picked up through a blood test rather than noticed directly, and doctors may check magnesium when these other minerals come back low.
8. Seizures
In severe cases, very low magnesium can cause seizures. This is a medical emergency, and anyone experiencing a seizure should seek urgent medical help. Severe deficiency at this level is rare and is usually linked to an underlying medical condition rather than diet alone.
Who Is More at Risk?
Some groups are more likely to have low magnesium levels than others. These include people with gastrointestinal conditions that affect absorption, such as Crohn’s disease or coeliac disease, and people with type 2 diabetes, who can lose more magnesium through their urine. Older adults are also at higher risk, as absorption tends to fall and losses tend to rise with age.
Long-term alcohol dependence is another common cause. Certain medications can also lower magnesium levels, including some diuretics and proton pump inhibitors (PPIs) when taken over a long period. If you fall into any of these groups, it is worth discussing your magnesium status with your GP.
How to Get Enough Magnesium
In the UK, the NHS advises that adults aged 19 to 64 need around 300mg of magnesium a day for men and 270mg a day for women. Most people should be able to get this from a varied, balanced diet. Good sources include green leafy vegetables such as spinach, nuts and seeds, wholegrain bread and brown rice, beans and pulses, and fish.
Some people choose to take a magnesium supplement. The NHS advises that taking 400mg or less a day from supplements is unlikely to cause any harm, while high doses can cause side effects such as diarrhoea. People with kidney disease should not take magnesium supplements without medical advice, as their bodies may be less able to remove excess magnesium. Magnesium can also interact with some medicines, so it is sensible to check with a pharmacist or GP before starting a supplement.
