top of page

Three key nutrients you're probably lacking & the devastating impact it can have on your health

Updated: Nov 17, 2021


Vitamins and minerals are vital to development, disease prevention, and well-being.

Yet I have found there are three key nutrients that the average New Zealander is commonly lacking.

A poor diet of overly processed, nutrient poor foods is the most obvious reason for the undernourishment. But the nutrient content in our soil (in NZ, our soil is naturally lacking many minerals), modern farming methods (failure to remineralise our soils), stress (increases the rate we use nutrients), environmental toxins (bind to the nutrients so they can't do their job), poor gut health (interferes with digestion and absorption of nutrients), and medications (interfering with nutrient absorption) all play a role.


So here are my top 3 nutrients you should make sure you're getting enough of:


1. Magnesium

Considered the wonder nutrient, it has been recognized as a cofactor for more than 300 important enzymatic reactions within our bodies. Magnesium...

  • is involved in muscle relaxation and contraction (remember the heart is a muscle)

  • is calming & can help alleviate the effects of stress on the body

  • detoxifies the body

  • is involved in brain and nerve function, digestion, glucose and energy metabolism, and in the maintenance of hormones

  • is important for bone health - possibly more so than calcium (calcium without magnesium makes bones hard but brittle).

  • is crucial for energy production, blood glucose control, and blood pressure regulation.

Common signs and symptoms of magnesium deficiency include:

  • Muscle and joint aches and pains

  • Headaches

  • Brain fog, poor memory or cognitive function (especially when under stress)

  • Anger and irritability (tantrums in children)

  • Fatigue

  • Poor sleep and insomnia

  • Sugar cravings

  • Chocolate cravings (chocolate is high in magnesium)


More serious conditions linked to magnesium deficiency include

  • Cardiovascular disease

  • Hypertension (high blood pressure)

  • Calcification of soft tissues like arteries and ligaments

  • Type 2 Diabetes

  • Anxiety and depression

  • Nerve damage

  • Sensitivity to light and sound

  • Osteoporosis

  • Seizures

  • ADHD

  • Obsessive compulsive disorder

  • Infertility

  • PMS (premenstrual syndrome)

  • Fibromyalgia

  • Musculoskeletal problems

  • Kidney disease

  • Asthma

How do you assess your magnesium levels?

Because only 1% of magnesium is in the blood, a standard serum blood test is not very reliable. Measuring the magnesium level within red blood cells however is more accurate. Since this test is not funded in New Zealand, you will need pay for it. Make sure you request a red blood cell magnesium test. Functional medicine practitioners recommend that the optimal range is 6.0 - 6.5 mg/dL or around 2.5 - 2.7 mmol/L.


How do you increase magnesium intake and which supplements are recommended?

Magnesium is a supplement I believe everyone should be taking. Research has indicated that magnesium deficiency could be as high as 80% of the population!!!

Please be aware, not all magnesium supplements are created equal. Each type also has a slightly different targeted purpose (indicated in brackets).

Recommended supplement intake of magnesium for an adult is usually around 300 mg per day.


Good forms of magnesium include:

For some of my favourite brands, click the links provided or view the full list here.

Magnesium L-threonate (brain health, memory)

Magnesium glycinate or bisglycinate (general purpose, sleep, cardiovascular)

Magnesium taurate (cardiovascular / heart health)

Magnesium citrate (constipation)

Magnesium citramate or citra-malate (muscle aches / fibromyalgia)

Magnesium orotate (athletic performance & endurance)

Magnesium chloride (ionic magnesium)


Absorption of magnesium in our gut can be challenging for most and worsens with age.

So absorption through our skin is another way to increase magnesium levels. Use Epsom salts, magnesium bath salts or magnesium flakes in your bath or as a foot soak. Or use a magnesium chloride spray or lotion on the skin daily.


Avoid supplements containing:

Magnesium oxide, magnesium sulphate, magnesium phosphate, magnesium hydroxide, magnesium aspartate and magnesium glutamate.



Magnesium rich foods include:

  • Green leafy vegetables (e.g. spinach and kale)

  • Fruit (figs, avocado, banana and raspberries)

  • Nuts and seeds.

  • Legumes (black beans, chickpeas and kidney beans)

  • Vegetables (peas, broccoli, cabbage, green beans, artichokes, asparagus, brussels sprouts)

  • Seafood (salmon, mackerel, tuna)

2. Zinc

Zinc is another critical nutrient that acts a cofactor for a lot of important reactions in the body. Including the synthesis and replication of DNA and vital proteins.

It is required to produce stomach acid, which enables adequate digestion and offers a first line of defense to any ingested pathogens or disease causing microbes.

It is antibacterial and antiviral, which is why it is found in every cell and all body fluids, including tears, saliva, mucus and sweat.

As well as providing immune support, it supports the detox of your blood and tissues from toxic metals. It helps protect the brain and gut lining, and fixes damage to the liver.

It is important in fertility and hormonal health for both men and women.

It is estimated by the World Health Organisation that about 30% of the world's population are zinc deficient!



What are the signs and symptoms of a zinc deficiency?

  • Poor memory and cognitive function

  • Poor growth (including babies in utero)

  • Hair loss

  • Skin conditions (including acne)

  • Poor taste and appetite

  • Inflammation and allergies (zinc helps reduce histamine levels)

  • Low libido

  • Frequent infections and poor immune health

  • Poor wound healing

  • Poor night vision

  • Low mood

  • White spots on your finger nails

You are at risk of a zinc deficiency if...

  • You live in New Zealand, as our soil is lacking zinc.

  • Rarely eat seafood such as oysters and shellfish, or foods such as pumpkin seeds, sunflower seeds, red meat, eggs, kidney beans, and dark leafy greens.

  • Consume large quantities of milk and dairy products (the casein protein affects absorption).

  • Have a poor diet filled with processed foods or chronic gut issues.

  • Have amalgam fillings and eat loads of tuna, shark, swordfish and other large fish (mercury in these products will compete with binding sites for zinc).

  • Are an athlete or someone that sweats a lot.

  • Have a high stress lifestyle.

  • Have or had a copper IUD for an extended period of time or have been exposed to copper regularly (eg. in a job or water pipes). Copper also competes for the same binding sites in the body, so if copper gets higher than around 80% of the zinc in the body then symptoms of zinc deficiency can emerge (regardless of how much zinc you have in your system).


Consider getting your zinc status assessed especially if you...

  • Are pregnant or breastfeeding.

  • Are having or had issues with fertility.

  • Have had premature or low birth weight babies.

  • Have anxiety or depression.

  • Have learning difficulties or poor memory or cognitive function.

  • Have or are at risk of Alzheimer's disease.

  • Have a thyroid disorder.

  • Have prostatic enlargement.

  • Are elderly.

  • Have diabetes or pre-diabetes.

  • Have dental cavities or poor dental health.

  • Have any chronic illness or are constantly sick with infections.

  • Have body image issues.

  • Have a problem with weight gain.

How do I test for a deficiency and how do I supplement if needed?

Unfortunately blood tests do not provide an accurate assessment of zinc status. However a serum copper:zinc ratio test can be helpful and should be 0.8 to 1. (Again, you need to request and pay for this test in New Zealand).

A zinc taste test is the most common way to indicate zinc status. Deficient individuals will find drinking liquid zinc sulphate as having little to no taste. An unpleasant taste immediately on drinking means the person as achieved the optimal level. Many pharmacies offer this test for free.

Zinc picolinate, zinc bisglycinate, zinc sulphate and ionic zinc (zinc chloride) are common forms used for supplementation.

Avoid taking zinc supplements on a empty stomach as it can cause nausea and (rarely) vomiting.

Excess zinc intake can interfere with magnesium, copper and iron metabolism, so I'd recommend supplementing only with support from a health practitioner.


3. Vitamin D

Why is it critical to your health?

This important vitamin is actually a steroid hormone. It is involved in so many crucial processes in the body, particularly the immune and hormone systems. It inhibits inflammation and supports the body's infection fighting ability. It is essential for healthy bones and teeth, and works with vitamin K in blood clotting and bone health. It provides cardiovascular and respiratory support, plus protects the brain and nerve cells.

Around one third of the NZ population according to a 2008/9 report are vitamin D deficient.



What can deplete vitamin D levels?

  • Lack of sunlight exposure (most of your vitamin D is produced in the body from exposure to sunlight)

  • Frequent sunscreen use (blocks production)

  • Excess calcium intake

  • Vegan diet

  • Alcohol consumption

  • Some pharmaceutical medications

  • Gut problems

  • Pollution

  • Kidney disease

What conditions are linked to a vitamin D deficiency OR may benefit from supplementation?

  • Depression

  • Anxiety

  • Autoimmune diseases eg. multiple sclerosis

  • Diabetes

  • Osteoporosis

  • Insomnia

  • Cancer

  • Fatigue

  • Infertility

  • Joint pain and achy bones

  • Cognitive Impairment

  • Hyperparathyroidism

  • Cardiovascular disease

  • Irritable bowel or leaky gut (Vitamin D helps maintain the integrity of the tight junctions)


How do you test for a vitamin D deficiency?

A blood test measuring 25-hydroxy vitamin D is the recommended assessment. Unfortunately there is a cost for this test in New Zealand as the government and health board do not see the necessity of this test, YET. The cost is around $80 NZ. You can request a lab referral through your GP, naturopath or functional medicine / holistic health practitioner.


From a functional medicine point of view, ideal vitamin D levels are around 100 nm/L. Many non-functional or non-holistic practitioners will unfortunately view a level around 30 nm/L as adequate, which is extremely disappointing.

Vitamin D toxicity is very rare and usually only occurs in levels above 500 nm/L.


How do you improve your levels?

  • Expose your body (without sunscreen) for around 20 to 30 minutes 3 x per week.

  • Consume oily fish, egg yolks, beef and organ meat.

  • Supplement with a product such as Thorne Vitamin D/K2 liquid. (I prefer to use a combined D3 and K2 supplement).


It is vital for good health to make sure you have adequate levels of these critical nutrients. However there are other common deficiencies to be aware of, including: omega 3 fatty acids, iodine, selenium, vitamin C, vitamin A, and B vitamins. Especially B6 (P5P is its active form), B12 (methyl B12 is its active form) and B9 (methyl folate is its active form).

Nourishing your body with local organic produce is the best way to avoid nutrient deficiencies, though unfortunately supplementation is becoming more and more necessary in these modern times.


bottom of page