Twitchy legs, cramps, sore muscles and feeling tired? You may need to check your magnesium levels
What is magnesium?
It’s the fourth most abundant mineral in the body. About 50 per cent of your body’s magnesium is contained in your bones, while the remainder is inside your tissues and organs. Magnesium is important in more than 300 chemical reactions that keep the body working properly. People get magnesium from their diet, but sometimes magnesium supplements are needed if magnesium levels are too low. Dietary intake of magnesium may be low, particularly among women.
- Spinach and kale (but don’t over cook)
- Seeds (pumpkin seeds are a great source)
- Nuts (particularly almonds)
- Whole unrefined grains
- Halibut and Mackerel
The Benefits of magnesium
As it’s found in the bones it’s needed for bone health, along with other nutrients such as calcium and vitamin D.
Heart and blood pressure
Magnesium is necessary in the transport of ions that conduct nerve impulses for normal muscle contraction, and heart rhythm, and a deficiency can result in arrhythmias (irregular heart beat, too fast or too slow). Magnesium deficiency can also lead to higher blood pressure (but take too much and your blood pressure can drop).
In 2006 researchers found that low levels of magnesium impact on muscle function: including oxygen uptake, energy production and electrolyte balance. A deficiency in magnesium can also result in calcium deposits staying in the cells, which can restrict muscle contraction. This, too, can lead to lactic acid build up and that painful muscle cramping, and twitches. The right levels of magnesium can help active people and endurance athletes recover from exercise by allowing muscles to contract and relax effectively.
Magnesium is responsible for synthesis of ATP (Adenosine Triphosphate – known as the ‘energy currency’ of cells) energy. ATP energy is released for all muscle contractions and when we exercise it needs to be synthesised quickly.
When to take a supplement
We lose magnesium when we sweat and if you’re someone who enjoys strenuous exercise you should consider taking a supplement as it can, according to research, increase urinary and sweat losses that may increase magnesium requirements by 10 to 20 per cent (Nielsen and Lukaski 2006).
Lactic acid is produced when oxygen in the body becomes limited through strenuous activity, and this can cause a ‘burn’ in your legs. Research, including a Turkish study which looked at 30 people following a four-week jumping training programme has concluded that magnesium supplements can help lower lactate levels. Another round up of research from 2000 found competitive rowers who took a magnesium supplement (360 mg/d) for four weeks had lower serum lactate concentrations and 10 per cent lower oxygen uptake during a controlled submaximal exercise test.
The UK recommended intake for magnesium is 300mg for men and 270mg for women. In the US, the recommendation is higher but recent surveys have found that some 57 per cent of the US population is not meeting the recommended levels. And some experts argue athletes need more than this – as much as 500mg a day. Magnesium supplements are available in many formats and often are often combined with vitamin D, or calcium, to help boost bone health.
Oils and Bath Salts
Magnesium can be absorbed through your skin and help to displace the calcium ions that may cause muscle cramping and restlessness and some say it’s a more effective way to take magnesium and helps to avoid overdose (which can result in diarrhoea). Note when using oil, check to see if it has black pepper added; this can make itching and irritability associated with magnesium oil worse! Epsom Salts contain magnesium, too and added to a bath make for a fantastic post workout recovery.