Do you need more magnesium?

When thinking about important minerals in the body such as calcium and iron, many forget about magnesium  even though it is involved in over 300 processes in the body.

What is magnesium?

Magnesium is a key mineral, involved in almost all of the body’s major cellular metabolic and biochemical processes. However, despite its importance, many are unaware if they are consuming enough in their diet. Magnesium is a macro-mineral which is needed by the body in large amounts. The mineral is found in a wide variety of foods including green leafy vegetables, bananas, brown rice, whole grain bread, fish and dairy foods. The NHS recommends 300 mg of magnesium a day for men (19-64 years) and 270 mg a day for women (19-64 years) [1].

Within the body, magnesium, along with oxygen and hydrogen, is amongst the 11 elements that are necessary for life. Magnesium is essential for many different processes in the body including maintaining healthy bones, energy production, normal nerve and muscle function, regulating blood pressure and blood sugar levels as well as aiding the production of DNA - the body’s genetic material. Magnesium may have a role in insulin secretion and epidemiological studies have shown a high prevalence of lower intracellular magnesium concentrations in diabetics [2].

How much magnesium do we need?

Over the last few years, the number of people who are deficient in magnesium has risen and low magnesium is often referred to as ‘the silent epidemic of our time’. The daily recommended amount of magnesium would once have been easy to obtain from eating green leafy vegetables and meat but intensive farming has had an effect on the magnesium content of crops. Our fast-paced, modern-day lifestyles may also be to blame for our low magnesium levels as the stress hormones adrenaline and cortisol can deplete the body’s magnesium stores. Alcohol and caffeine both act as magnesium diuretics; meaning they can increase the urinary excretion of magnesium from the body.

What are the symptoms of low magnesium?

Because the symptoms of low magnesium are not unique to a magnesium deficiency, low magnesium levels can be very difficult to pinpoint and diagnose. Symptoms include:

  • Muscle cramps
  • Fatigue
  • Eye twitches
  • Irregular heartbeat
  • High blood pressure
  • Problems sleeping
  • Low mood

Many people who are magnesium deficient go undiagnosed for a long while as severe symptoms don’t often appear until levels are extremely low.

Are you getting magnesium?

How are your magnesium levels?

Because quite often low magnesium levels go unrecognised, many people suffer from the symptoms of a deficiency when something as simple as increasing their dietary intake of magnesium could really help them feel better.

The majority of the magnesium present in the body is stored in bone and muscle. The most common method for testing magnesium levels is a serum blood test which although shows the level of magnesium in the blood, does not show the amount of magnesium that is actually getting absorbed into the soft tissue [2]. Red blood cell (RBC) magnesium is a measure of the magnesium in the red blood cells. Compared to serum magnesium, RBC magnesium is considered a more sensitive measure of magnesium in the body because when serum magnesium decreases, magnesium is pulled out of the red blood cells to stabilise the decrease. As a result, serum magnesium will remain normal even as magnesium levels in the tissue are decreasing and therefore RBC magnesium is a greater responsive indicator of the body’s magnesium levels.


[1] (2019). Vitamins and minerals. [online] Available at: [Accessed 24 Jun. 2019].

[2] Jahnen-Dechent, W. and Ketteler, M. (2012). Magnesium basics. Clinical Kidney Journal, 5(Suppl 1), pp.i3-i14.

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