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Common Nutrient Deficiencies and How to Avoid Them

Dietary nutrient deficiencies are very common in today’s world often due to the types and quality of food we are eating. They are also sometimes hard to avoid if you follow a specific diet e.g. vegan/vegetarian, paleo, Atkins, ketogenic etc.

Often if you are deficient in certain nutrients, you will show the common deficiency symptoms. Although this is not true for all. Some nutrient deficiencies go unnoticed until further down the line where the deficiency may become more severe.

The most common nutrient deficiencies include:

  • B vitamins
  • Vitamin C
  • Vitamin D
  • Zinc
  • Calcium
  • Magnesium
  • Iodine
  • Iron
  • Selenium
  • Antioxidant
  • Essential fatty acids
  • Amino acids

The most common method to confirm deficiencies are blood tests. However, to gain a full spectrum overview of all nutrients and deficiencies, this can be costly as they are not all funded. The Epigenetics Wellbeing Assessment (EWA) here at Global Health provides a detailed overview of the nutrients you are likely to be deficient in, based off only one test which provides more than just nutrient deficiencies.

Sometimes you may require supplements if your body stores are too depleted, however with the right knowledge it can be easy to increase your dietary intake and help to reverse these deficiencies.

Make sure to keep reading to find out about the most common nutrients deficiencies, the signs and symptoms of these deficiencies, foods to include to help avoid them and how to book in an EWA for yourself!

The Most Common Nutrient Deficiencies

Stress / B Vitamins

The B vitamins include a wide range of vitamins including B1, B3, B5, B6, B7, B9 and B12. They work together in many bodily processes including energy production, stress regulation, metabolism, and DNA repair. Stress, heavy exercise, growing children, post anti-biotic use and pregnancy are all factors which increase the need for B vitamins.

Each B vitamin has specific food sources, however if you are generally eating a whole foods diet with leafy green vegetables, beans, fruits, vegetables yeast foods and eggs, it is likely you are eating a wide range of these vitamins. Vitamin B12 is an exception, however, see below for more detail specifically regarding Vitamin B12.

Vitamin B12

Vitamin B12 has a range of functions including red blood cell production, new cell growth and replication, modulating cellular immunity, carbohydrate, protein and fat metabolism and is part of energy production.

Deficiency symptoms can include fatigue, pale skin and mucous membranes, muscle weakness and dizziness.

The recommended daily intake for adults is at least 2.4 micrograms/day. Vitamin B12 is mainly found in animal products including meats (livers, sardines and oysters), however some fortified breakfast cereals contain B12 as well as smaller amounts in milk cheese and eggs. If you follow a vegan or vegetarian diet, it is recommended to supplement vitamin B12 to ensure you are reaching your daily recommended intake.

Vitamin C

Vitamin C is a potent antioxidant, and all its known functions are attributed to this. Vitamin C functions in collagen synthesis, energy metabolism, cholesterol metabolism, enhancing immune function, enhancing iron absorption and supports the functioning of the adrenal glands and arterial functions.

Deficiency symptoms of vitamin C can include poor immunity, poor wound healing, dry skin, fatigue, muscle weakness and irritability.

For adults over 19 years, at least 45 milligrams/day is required. However, people often thrive on having higher doses of vitamin C. By including 2 green kiwifruit per day, you have already had just less than 200 milligrams. Other food sources with high vitamin c content include capsicum, strawberries, broccoli, and kumara. Including fresh fruits and vegetables of different colours will ensure you gain more than the minimum requirement, supporting your body in a wide range of functions.

Vitamin D

Vitamin D is very important for bone growth as it functions in maintaining the amount of calcium required for strong bones. Vitamin D is also important in regulating the immune system as well as insulin secretion.

Deficiency of vitamin D can result in osteoporosis in adults from a loss of calcium resulting in soft, flexible, brittle and deformed bones as well as lowered immunity.

For adults 19-50 years, at least 5 micrograms/day is required, adults 51-70, at least 10 micrograms/day is required and adults over 70, at least 15 micrograms per day is required. Vitamin D is most bioavailable from the sun. 2-3 hours of safe sun exposure over a week is all that is required for you to gain optimal vitamin D. However, the best food sources of vitamin D include fatty fish and their oils (salmon, tuna, sardines), beef, liver, eggs, fortified food and mushrooms if exposed to sunlight.


Zinc is an essential trace mineral for the functioning of over 200 enzymatic and other cellular processes. Zinc is involved in cell replication and DNA synthesis, immunity, wound healing, sperm development, carbohydrate metabolism and the normal functioning of your thyroid.

Zinc deficiency can show with symptoms of poor wound healing, skin lesions/dermatitis, reduced immunity and loss of hair, taste, and appetite.

The recommended daily intake of zinc is at least 14 milligrams/day for men and at least 8 milligrams/day for women. It is important to make sure you are reaching this intake due to the wide range of functions zinc has. Often if you are not eating enough protein, you will not be getting enough zinc. Including foods such as red meats, oysters, seafood, dairy, whole grains and pumpkin seeds will help you reach the daily intake target.


Calcium is the most abundant mineral in and body and most known for its function in bone growth and maintenance. This is true as calcium helps to form the structure of bones as well as harden the exterior. Calcium is also involved in muscle contractions, maintaining blood pressure and ensuring healthy functioning of the heart.

Deficiency of calcium can result in osteoporosis where your bones become porous and fragile due to mineral losses. This can result in soft, flexible, brittle and deformed bones. In children, calcium deficiency can result in stunted growth as there has not been enough calcium for bone growth and formation.

The requirement of calcium for women aged 19-50 and men 19-70 is the same, at least 1000 milligrams/day. However, women aged 50+ or post menopause require a greater amount, at least 1300 milligrams/day. Calcium is found in milk and milk products, seafood such as small bony fish, salmon and oysters, legumes, broccoli and fortified soy and rice milks and breakfast cereals.


Magnesium is involved in over 300 biochemical processes in the body including energy production, normal muscle contractions, DNA synthesis, bone formation, carbohydrate, lipid and protein metabolism and much more.

Deficiency of magnesium can cause weakness and confusion and growth failure in children. Deficiencies can result from inadequate protein intake, alcohol abuse, kidney disorders and prolonged diarrhoea and vomiting.

For men 19 and over, at least 400 milligrams/day is required. For women 19 and over, at least 310 milligrams/day is required. However, both these needs increase with age. To ensure you are gaining enough magnesium in your diet, is best found in wholegrains, dark green vegetables, seafood, dairy, nuts and legumes and cocoa/dark chocolate.


Iodine is extremely important for the functioning of your thyroid as it is involved in the formation of both T3 and T4 thyroid hormones. Your thyroid is involved in your body’s metabolism, growth, and development and therefore iodine is essential.

Iodine is often deficient in New Zealanders due to low levels in our soils. Deficiency symptoms can include the presence of a goitre in your neck where your thyroid is located, hypothyroidism (low functioning of your thyroid due to low levels of thyroid hormones) and poor memory and cognitive function.

For adults, at least 150 micrograms of iodine is required/day. Iodine is best found in seafoods including muscles and snapper as well as kelp, nori and dulse. However, iodine can also be found in iodised salt, bread or any plants grown in iodine rich soil. By including these foods in your diet each day, you can ensure you are getting this essential nutrient in your diet.


Iron is another micronutrient with a wide range of functions. Iron is involved in transporting oxygen around your body from your lungs to body tissues, energy production, improving immunity and cognitive function.

Iron deficiency is the number one deficiency in the world and is most common in vegans/vegetarians as well as women of reproductive age. It often begins gradually and can result in iron deficiency anaemia in severe states. Signs and symptoms can include pale skin, short attention span, fatigue, decreased work performance and productivity, more common infections and anaemia detected by blood tests.

Haem iron is better absorbed in the body and is found in animal products such as meats, chicken, oysters and fish. Whereas non-haem iron is not as well absorbed by the body and is found in plant foods such as vegetables, nuts, seeds and whole grains. Combining iron containing food sources with foods rich in vitamin C such as kiwifruit, oranges or broccoli, this can enhance iron absorption in your body and is recommended for everyone, especially those following a vegan or vegetarian diet.


Selenium acts primarily as an antioxidant nutrient. Selenium is part of one of the bodies most potent antioxidants, glutathione peroxidase. Additionally, selenium helps to regulate your thyroid hormones and subsequently the functioning of your thyroid. Both these roles stress the importance of selenium in your diet.

Deficiency in selenium can be common where there is a deficiency of selenium in the soils. This is also common in New Zealand along with iodine. Deficiency can result in hypothyroidism, thyroid goitre, muscle pain and weakness, poor growth, impaired cognitive function and poor immunity.

For men 19 years and older, at least 70 micrograms/day is required. For women 19 years and older, at least 60 micrograms/day is required. Sources of selenium include Brazil nuts, wheat products, meats and eggs. Including these food sources in your diet will be help you to reach the recommended daily target and help avoid deficiency.


Antioxidants are substances that are in food that neutralise free radicals or their actions in the body. Free radicals can cause oxidative damage, heart and nerve cell damage, trigger certain cancers and accelerate the aging process. Vitamins A, C and E act as antioxidants as well as selenium and zinc. Antioxidants found in foods are more potent than those in supplements and so it is important to eat a wide range of antioxidant containing foods. These include fresh fruits and vegetables of different colours, including from strawberries, raspberries, red, orange and yellow capsicum, grapes, spinach and kale.

Essential Fatty Acids

Essential fatty acids (EFA’s) are ‘essential’, as the body cannot produce them itself and must obtain them from dietary sources. Though you have probably often heard the word ‘fats’ and associated it with bad health, there are some essential fatty acids that are necessary for your survival.

The two types of EFA’s include omega-3 and omega-6. Lots of focus is on omega-3 EFA’s, however they are both as important to include in your diet. Omega 3 fatty acids include mackerel, salmon, cod liver oil, oysters, sardines, chia seeds and flax seeds. Omega 6 fatty acids walnuts, hemp seeds, sunflower seeds, peanut butter, tofu, avocado oil, eggs, almonds and cashews.

Amino Acids

Amino acids are the building blocks of proteins. Protein is needed by every living organism, and next to water, makes up the largest portion of our body weight since it is contained in muscles, organs, hair, etc. The protein used in making up the body is not directly derived from diet, but the dietary protein is broken down into amino acids, and the body then re-constitutes these amino acids into the specific proteins needed.

There are essential amino acids and non-essential amino acids that the body requires to function. Essential amino acids are required from the diet as the body cannot produce them itself. Therefore, it is important that your diet contains ‘complete’ sources of proteins as they contain all these essential amino acids. Examples of complete protein sources to include are meat, fish, milk, yoghurt, cheese, eggs, quinoa, pumpkin seeds, buckwheat, hemp and soybeans.

Where To From Here?

If you are concerned about any dietary deficiencies that you may have, it is best to talk to a healthcare professional. Here at Global Health our team are experts in this field and can help you get to the bottom of your concerns. Booking in an EWA is the best place to start to gain a wide overview of dietary deficiencies you may have as well as understanding other areas of your health to focus on to maintain optimal health.

Click here to book in an EWA today.