Common nutrient deficiencies

As we know, many nutrients are essential for good health and wellbeing, with our body needing these nutrients to carry out the everyday functions that keep us alive.

It is possible to get most of our requirements from a balanced, real food-based diet, but with so much pre-packaged and processed food being consumed, the typical modern diet lacks several very important nutrients.


Iron is an essential mineral and the main component of red blood cells, where it is involved with transporting oxygen to cells.

There are two types of dietary iron:

  • Heme iron:
    • very well absorbed
    • found in animal foods, with red meat having particularly high amounts
  • Non-heme iron:
    • more common
    • found in both animal and plant foods
    • not absorbed as easily as heme iron

Iron deficiency is one of the most common nutrient deficiencies in the world, affecting approximately 25% of people in many developed countries including Australia.

Those most at risk include:

  • women due to monthly menstrual loss of blood
  • children during rapid growth – especially premature or low-birth weight babies, toddlers, preschoolers and during teenage years
  • vegetarians, particularly those who eliminate all animal foods from their diet. The iron in animal foods is more easily absorbed by the body than iron from plant foods
  • athletes due to the extra stress placed on their bodies
  • pregnant women – due to the increased demand for nutrients for the developing foetus

The most common outcome of iron deficiency is anaemia, where the quantity of red blood cells is decreased, and the blood becomes less able to carry oxygen throughout the body. Anaemia will usually present with symptoms including tiredness, weakness, weakened immune system and impaired (foggy) brain function.

To prevent anaemia or even a low-grade iron deficiency, it is important to eat a well-balanced diet that includes iron-rich foods including:

  • red meat
  • poultry
  • fish
  • eggs
  • dried beans and lentils
  • green leafy vegetables
  • nuts
  • seeds
  • wholegrain breads and cereals

Iron absorption from foods is improved by eating food rich in vitamin C within the same meal. Try citrus fruits, red capsicum or kiwi fruit. Eating meat, fish or chicken can also increase absorption of iron in plant foods when eaten at the same time.

Conversely, iron absorption can be reduced by tea, coffee and cola drinks if consumed at the same time.


Vitamin B12, is a water-soluble vitamin, essential for blood formation, brain and nerve function. Every cell in your body needs B12 to function normally, but due to the body being unable to produce it, we must get it from our food or supplements.

Vitamin B12 is only found in animal foods (with the exception of nori seaweed and tempeh). It is therefore common for vegetarians and vegans to be deficient, with some figures saying as many as 80–90% of these groups having a deficiency.

Absorption also decreases with age so elderly people are also at risk of a deficiency.

What doesn’t work in the favour of B12 is that it needs a specific protein to be utilised by the body. If someone is lacking this protein, they may need B12 injections or higher doses of supplements to reach the required ‘healthy’ level.

Common symptoms of vitamin B12 deficiency include:

  • specific form of anemia – megaloblastic
  • impaired brain function (foggy brain)
  • constipation and impaired gut function
  • increased tiredness
  • pins and needles in hands and feet
  • elevated homocysteine levels, which is a risk factor for several diseases

Dietary sources of vitamin B12 include:

  • shellfish, especially clams and oysters
  • organ meats such as liver
  • red meat
  • eggs
  • milk products


Calcium is essential for every cell in our body – from mineralising bones and teeth, it is also very important for the maintenance of our bones as well as being the ‘communicator molecule’ for the entire body. Without it, our nerves, muscles and heart would stop functioning. An amazing nutrient!

Calcium is strictly regulated in the body in the blood stream. Excess is stored in our bones so, when there is a lack in the diet, it is taken from the bones with detrimental effect, with a common deficiency being osteoporosis – soft and fragile bones.

Many of us don’t meet the recommended daily intake of calcium – the best sources are from our diet, although supplements can help too.

Dietary sources of calcium include:

  • boned fish
  • dairy products
  • dark green vegetables, such as kale, spinach, bok choy and broccoli
  • nuts


Iodine is an essential mineral for normal thyroid function and the production of thyroid hormones – the hormones involved in growth, bone health, brain development, metabolism.

Iodine deficiency is one of the most common nutrient deficiencies in the world. It affects almost one-thirdof the world’s population!

Recognising an iodine deficiency can be challenge as so many of the symptoms are quite general. However, a common symptom is an enlarged thyroid gland, also known as goiter. You may also notice an increased in heart rate, shortness of breath, weight gain, increased fatigue and some hair loss.

Severe iodine deficiency may also cause serious adverse effects, especially in children. These include mental retardation and developmental abnormalities.

Good dietary sources of iodine:

  • seaweed (like the stuff wrapped around sushi rolls)
  • fish, oysters
  • dairy products
  • eggs
  • mushrooms

The amounts of iodine in products can vary greatly due to the iodine in most products coming from the soil in which it is grown or the sea it comes from. As such, iIf the soil quality is iodine-poor then the food growing in it will be low in iodine also.

Vitamin D:

Vitamin D is a fat-soluble vitamin with a big role in the body – almost every cell in the body has a receptor for it and it travels through the blood communicating with cells advising them to turn certain genes on or off.

Some of the vitamin D we need is produced through the skin via cholesterol, when it is exposed to sunlight. However, this method of production is inconsistent across the population as we all have different levels of exposure to the sun at different times of the year and we all have different skin types.

Although in Australia we have high-levels of sunlight, many people remain very covered up in fear of sunburn, meaning, as a population are one of the most vitamin D deficient countries in the world!

A deficiency in vitamin D is not usually visible with the symptoms being very subtle and they often develop over a number of years.

Some symptoms in adults are:

  • muscle weakness
  • bone loss and increased risk of fractures
  • reduced immune function

In children, it may cause growth delays and soft bones.

Getting adequate amounts of vitamin D through our food is a challenge due to no food containing particularly high amounts. The best sources are:

  • cod liver oil
  • fatty fish, such as salmon, mackerel, sardines or trout
  • egg yolks

People who are very deficient in vitamin D may want to take a supplement or increase their sun exposure. It is very difficult to get sufficient amounts through our diet alone.

Vitamin A:

Vitamin A is an essential fat-soluble vitamin that helps form and maintain healthy skin, teeth, bones and cell membranes. It also produces the elements of the eyes necessary for vision.

Within the diet there are 2 forms of vitamin A:

  • pre-formed vitamin A: found in animal products like meat, fish, poultry and dairy
  • pro-vitamin A: found in fruits and vegetables. Beta-carotene is the most common form of this type of vitamin A, which the body then converts

The majority of people eating a well-balanced diet will be getting enough vitamin A. However, vitamin A deficiency is very common in many developing countries , especially children.

A deficiency can cause both temporary and permanent eye damage, and may even lead to blindness – it is the world’s leading cause of blindness.

Vitamin A deficiency can also suppress immune function especially among children and pregnant or lactating women .

Dietary sources of pre-formed vitamin A include:

  • organ meat
  • fish liver oil

Dietary sources of beta-carotene (pro-vitamin A) include:

  • sweet potatoes
  • carrots
  • dark green leafy vegetables

While it is very important to consume enough vitamin A, it is generally not recommended to consume very large amounts of pre-formed vitamin A, as it may cause toxicity. The same does not apply pro-vitamin A, (beta-carotene).


Magnesium is a very important mineral in the body, essential for bone and teeth structure, as well as being involved in more than 300 enzyme reactions throughout the body.

Many of us don’t consume enough magnesium in our diets and, low levels have been associated with several diseases, including type 2 diabetes, metabolic syndrome, heart disease and osteoporosis.

Many things affect magnesium levels in the body including certain prescription medications. Consult with your healthcare practitioner if you are taking any prescription medication before supplementing with magnesium.

The main symptoms of severe magnesium deficiency include abnormal heart rhythm, muscle cramps, restless leg syndrome, fatigue and migraines. More subtle, long-term symptoms that may not be so noticeable include insulin resistance and high blood pressure.

Good dietary sources of magnesium include:

  • whole grains
  • nuts – almonds and cashews are the highest sources
  • seeds – sunflower, flaxseeds, chia
  • figs
  • dark chocolate (cocoa content higher than 60%)
  • leafy, green vegetables

A well-balanced diet is the best way to start ensuring your getting adequate amounts of all nutrients. Need some input into your diet, healthcare and lifestyle? Call us at the Natural Chemist for a consult with one of our expert team of nutritionists and naturopaths. T: 1300 882 303.

Always consult a healthcare practitioner before self-prescribing any nutritional supplement.

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