The mineral magnesium is becoming increasingly more popular amongst supplement users - but why?
Before we can answer this, we need to break the science down…
Why do I Actually Need Magnesium?
Just like any micronutrient, magnesium plays a crucial part in maintaining our health. This includes aiding the metabolism of food into energy (1,2). We need energy for numerous bodily processes - and let’s be real here, this makes it a crucial function!
Magnesium also helps the maintenance of bone health (2). Bone health is important since our bones provide an enormous amount of structure and support to our bodies (imagine if we didn’t have a skeleton… or our brain wasn’t protected by our skull!?) (3). Not only this, but by trying to maintain good bone health, we reduce our risk of osteoporosis, which is the weakening of bones due to reduced bone density and mass (4).
Other functions, equally as important, include healthy functioning of muscles and nerves, and supporting the function of the parathyroid glands, which in turn also supports bone health (1,2).
So, Where Do I Find Magnesium?
Obtained from multiple foods, magnesium can easily be sourced in our diets - particularly plant-based foods. Nuts and seeds (particularly Brazil nuts and sunflower seeds [2]), leafy green vegetables (spinach, I’m looking at you), whole grains (e.g. wholemeal bread, brown rice and quinoa [2]) and beans (e.g. black beans) are all sources (1,2,5). You might find some breakfast cereals are fortified with magnesium - check the labels to see if magnesium is listed! Fortified breakfast cereals will differ in the nutrients added, based upon their intended target market.
What About When I Get Low in Magnesium?
Magnesium deficiency may cause the following symptoms (5):
Nausea and vomiting
Reduced appetite
Tiredness
Weakness
With prolonged magnesium deficiency, some individuals may report (5):
Numbness
Tingling
Cramps
Abnormal heartbeat
Personality changes
Low calcium or potassium levels
However, with a healthy, balanced diet, which includes the above listed foods, the risk of magnesium deficiency is low. If you have concerns, it is always important to visit your GP or a Registered (Associate) Nutritionist or Registered Dietitian.
What About If I Go Overboard with Magnesium?
The NHS suggest high magnesium doses (more than 400mg) could promote diarrhoea (1).
However, evidence is limited regarding the long-term effects of excess magnesium in the diet. But stop there, that’s not to say you can have as much magnesium as you want in your diet and you’ll never suffer any side effects. Simply put, there isn’t enough data for scientists to conclude anything - but this could change. Ultimately, balance is key.
Despite this, some individuals may have a slightly higher risk of having too much magnesium if they’re experiencing poor renal health or kidney failure, as the body’s ability to process and dispose of magnesium (and other nutrients) is adversely impacted (5).
The Big Question: Should I Supplement Magnesium?
Ultimately, this will depend from person to person. But I always believe, if you don’t actually need to supplement a nutrient… don’t. Whilst marketing might make you believe you must supplement, in reality if you don’t need to you’re simply wasting money.
Perhaps not the answer you were searching for, but each of our bodies are unique, and with differing diets, our magnesium (and general nutrient) levels will differ. This means that whilst your friend might need a magnesium supplement, you may not.
If you are concerned about your magnesium levels, please visit your GP or a Registered (Associate) Nutritionist or Registered Dietitian before supplementing.

References