The one thing about studying nutritional science is that you feel the urge to self-medicate. Vitamins and minerals can work synergistically, helping the body to feel healthier. However, it’s important to consult a doctor or nutritionist before supplementing with just any vitamins and minerals. This is because there are so many other factors to consider. Supplementing with a single vitamin may disturb the balance and cause a vitamin imbalance. This can have a knock-on effect throughout the body. I’m not saying supplementation is bad, I’m just saying…do your homework before going to the shops and buying into the first supplement sold to you.

There is one mineral which I find of particular interest. The more and more I understand about the body, the more I realise the importance of magnesium in over 300 bodily processes. With a large proportion of the population deficient in this essential mineral, I thought it deserved some special attention.

Magnesium (Mg) reserves are found 50% in bone and 25% in skeletal muscle. The rest is distributed throughout the body, mainly in the nervous system. Mg is not made in the body and needs to be taken in by the diet and other transdermal means. If the diet is deficient in Mg, one would need to look into additional supplementation.

It’s always good to look at the diet first and to try obtain all sources of vitamins and minerals through the diet.

Sources of Mg

  • Milk and water
  • Snails, haricot beans, walnuts, almonds, lentils, mussels, spinach, beetroot
  • Whole grains, meats, starches
  • Good quality coffee


The daily minimum uptake with a western diet is sufficient to avoid deficiency, although it is questionable whether our food contains good qualities of minerals due to farming methods. This is where choosing to eat organic comes into play.

Table showing breakdown of RDA for Mg

Life Stage Age Males (mg/day) Females (mg/day
Infants 0 – 6months 30 30
Infants 7 – 12 months 75 75
Children 1-3 years 80 80
Children 4-8 years 130 130
Children 9 – 13 years 240 240
Adolescents 14 – 18 years 410 360
Adults 19 + 400 – 420 310 – 320
Pregnancy and breastfeeding 310 – 360


  • Energy Production: Mg is required by the ATP-synthesising protein. ATP is required for most metabolic processes and exists primarily as a complex with Mg. (MgATP)
  • Synthesis of essential molecules: DNA, RNA, proteins and Glutathione, an antioxidant. Structural role in bone, cell membranes and chromosomes.
  • Cell signalling: MgATP is required for phosphorylation of proteins and formation of cell-signalling molecules cAMP.
  • Ion transport across cell membranes: eg. potassium and calcium. Mg affects the conduction on nerve impulses, muscle contraction and normal heart rhythm through ion transport system.
  • Mg has a balancing effect on excess calcium in the body, preventing cell death by cytotoxicity.
  • Magnesium is required by many coenzymes, such as in the conversion of LA to useable, anti-inflammatory form of omega 3 fatty acids.

Deficiency Symptoms

Luckily, the kidneys can also regulate urinary excretion when dietary intake is low. However, excessive and frequent alcohol intake may increase loss through urine. 

  • Adverse effect on lung function
  • Effects immune function and response to oxidative stress
  • Increased cardiovascular morbidity
  • Hypertension
  • Decreased bone mineral density
  • Insulin resistance (Increased risk of diabetes type 2)
  • Sodium retention/bloating
  • Muscle spasms
  • Poor sleeping patterns/restless sleep

The following can lead to Mg deficiency

  • Gastrointestinal disorders (Crohn’s, Celiac disease, diarrhoea)
  • Renal disorders (diabetes, long-term use of diuretics)
  • Chronic alcoholism
  • Age (increase age = decrease absorption of Mg)


Zinc: High doses of zinc can interfere with Mg absorption

Fibre: High intake of dietary fibre can result in lower Mg utilisation

Protein: Low protein intake is linked to lower Mg absorption

Vit D (Calciferol): Increase in VIT D may increase Mg absorption in the intestines.

Low Mg levels result in decreased serum calcium levels (hypocalcemia), lower serum potassium levels (hypokalemia), and low circulating levels of PTH (Parathyroid Hormone)

What does this all mean?

Since magnesium is essential for over 300 bodily processes, it is important to focus on valuable food sources. Since Mg can be obtained from meat, plant and grain products, it is easy to consume in any diet. The reason I have paid particular attention to Mg is that a deficiency in this mineral can have a knock-on effect in the body…So to think that rectifying one mineral balance could have a big effect on how you feel.

Can you have too much?

Overdosing on Mg is known to result in loose bowels. This is an indicative sign of overdose, and it would be a good idea to lower your dosage or discontinue use.

Overconsumption can compromise calcium absorption, as it inhibits calcium from entering the cells.


A perfect balance is optimal, which is why a varied diet is key. By varying the foods we eat throughout the week, we can make sure we are receiving the widest possible range of vitamins and minerals. Focus on Mg-providing foods and continue to shop organic as far as possible. Remember, before choosing to take the next step to supplementation, consult a trusted health care provider. Especially with Mg as there are so many forms on the market – some more easily absorbable than others.


I quite enjoy researching the effects of vitamins and minerals on the body, so watch this space for more info…



Mg is not made in the body and needs to be taken in by the diet and other transdermal means.
Almonds. walnuts, spinach, lentils and beetroot are all valued sources of magnesium
Include whole grains, meats, starches into your diet to increase magnesium uptake
Chicken close S
I'm not complaining with this one - your daily cup may be helping with increasing magnesium intake.