Micronutrients - What they are and dietary sources

In my post on macronutrients, I mentioned that there are micronutrients as well and that together macronutrients and micronutrients make up the nutrition that our bodies need. Even though we need both, micronutrients are needed in smaller amounts as compared to macronutrients.

Our micronutrients are going to be:

  • Vitamins
  • Minerals

In my opinion, macronutrients are talked about more rather than micronutrients. Additionally, this may be the opinion of others also. Micronutrients have important roles in the human body; micronutrients are important in energy production and metabolism. 

What if I tell you that a deficiency of micronutrients can lead to horrible consequences like poor growth, makes you prone to infections and can lead to death. Also, that these are only a few of the effects of micronutrient deficiency. Many people including children worldwide have micronutrient deficiencies.

More on each micronutrient!


Vitamins have a variety of functions in the human body. Our bodies need vitamins for growth and health [1]. There are signs that are present if there is a deficiency of a certain vitamin. There are 13 vitamins and they fall into two types. They are:
  1. water-soluble vitamins
  2. fat-soluble vitamins

The human body cannot synthesize all 13 vitamins that it needs. Some are produced in the gastrointestinal tract by bacteria and so we need to consume the other vitamins on a daily basis. It is important to know that even though our bodies can synthesize some that we may still need to consume them.

Water-soluble vitamins
These vitamins are not stored in the body and consequently, needs to be eaten every day.

The water-soluble vitamins are:
  • Vitamin B 1, 2, 3, 5, 6, 7, 9 and 12
  • Vitamin C (Ascorbic Acid)

Fat-soluble vitamins

Fat-soluble vitamins, on the other hand, are stored in fat cells and need fats to be transported and absorbed.

The fat-soluble vitamins are:

Vitamin A (retinol), D, E and K

A few vitamin roles

- Vitamin C is used in the production of collagen. It also aids in the absorption of iron [2].
- Vitamin D is necessary for the production and maintenance of strong healthy bones and teeth.
- Vitamin A strengthens the body's immune system and helps maintain normal vision.
Vitamin D, vitamin C, and zinc are essential to support normal immune function [3].

Some dietary sources of these vitamins

The B Vitamins/ vitamin B complex

Vitamin B1 (Thiamin) - whole grains, kale, asparagus, beans, peanuts, nutritional yeast

Asparagus. Image via pixabay.

Vitamin B2 (Riboflavin) - spinach, eggs, milk, meat, almonds

Eggs. Image via pixabay.

Vitamin B3 (Niacin) - beans, eggs, milk. red meat, tuna, salmon, mushrooms

Salmon. Image via pixabay.

Vitamin B5 (Pantothenic Acid) - legumes, meat, salmon, avocados, broccoli, yogurt

Broccoli. Image via pixabay.

Vitamin B6 (Pyridoxine) - brown rice, lentils, chicken, tuna, sunflower seeds, avocados, blackstrap molasses

Avocado. Image via pixabay.

Vitamin B7 (Biotin) - chicken, liver, potatoes, cauliflower, raspberries, nuts

Chicken. Image via pixabay.

Vitamin B9 (Folate) - beets, spinach, avocado, mango, salmon, milk, beans

Vitamin B12 (Cobalamin) - fish, shrimp, beef, beef liver, eggs, nutritional yeast

Shrimp. Image via pixabay.

Vitamin C - fruits and vegetables like citrus fruits, berries, apples, kiwi, spinach, peppers

Apples. Image via pixabay.

Vitamin A - dairy products, oily fish, fish liver oils, vitamin A fortify foods like cereals

Sardines. Image via pixabay.

Vitamin D - eggs, fish liver oils, vitamin D fortify foods like milk, orange juice, cereals, fatty fish, sunlight exposure

Milk. Image via pixabay.

Related post: How to get vitamin D without sunlight

Vitamin E - green leafy vegetables like spinach, avocado, vegetable oils, nuts like almonds, sunflower seeds

Spinach. Image via pixabay.

Vitamin K - green leafy vegetables like spinach, broccoli, cucumbers, strawberries, beans, eggs, produced by the bacteria in the intestine

Cucumbers. Image via pixabay.

Some vitamin deficiencies 

Vitamin deficiencies can cause diseases. Some are:

  • Scurvy - Results from a deficiency of Vitamin C.
  • Rickets -Results from a deficiency of Vitamin D [4].
  • Night blindness - Results from a deficiency of Vitamin A.
  • Pernicious anemia - Results from a deficiency of Vitamin B 12.


The Earth naturally contains minerals and these minerals can be found in the soil. We and other living organisms cannot make the minerals that we need in order to be healthy so how do we get these minerals? Plants obtain minerals from the soil through their roots. On the other hand, animals obtain their mineral requirement from eating plants and from eating other animals that have eaten plants. Humans source of minerals are from the plants and animals we use as foods. So it can be concluded that we and other living organisms are dependent on the Earth and each other for minerals.

Did you know that there are other sources of minerals? We can also obtain minerals from water, coconut water, other beverages, and supplements.

Some minerals that we require are:
  • calcium
  • magnesium
  • sulfur
  • iodine
  • chromium
  • sodium
  • copper
  • silicon
  • selenium
  • zinc
  • fluoride
  • iron
  • molybdenum
  • boron
  • manganese
  • potassium

Some dietary sources of a few minerals

Iron - beans, liver, meat

Copper - beans, eggs, fish, spinach

Calcium - milk

Potassium - banana

Magnesium - green leafy vegetables, seafood

Iodine - iodized table salt, eggs, soy milk

Selenium -  beef, eggs, cottage cheese, oatmeal

Deficiency of minerals

  • Iron deficiency which can lead to iron-deficiency anemia
  • Iodine deficiency which can lead to goiter.

Related post: I have iron-deficiency anemia, should I be concerned?

Some roles of two minerals are :

Calcium is needed for the formation of bones and teeth.
Potassium maintains water balance in the body and prevents muscle cramps.


What causes it?
Situations that cause micronutrients loss or increase are:

⇒ Poor diet
With a poor diet, it can be:
- not eating enough
- not eating the right foods or a variety of foods
- eating too little of healthy foods or none and lots of processed unhealthy foods and so on.

⇒ Food preparation
The cooking, preparation, and processing of foods can lead to the loss of micronutrients. For example boiling vegetables will lead to the loss of micronutrients.
Related post: 4 tips on how to get the most nutrients from the vegetables that you boil

⇒ Illness/disease
Diseases can lead to the loss or increase for micronutrients. Also, due to illness the absorption and transportation of micronutrients may disrupt, our metabolic requirements may increase and micronutrient loss may occur.

Parasitic infections can cause micronutrient loss. For example, the parasitic hookworm feeds on the blood of humans. This loss of blood can lead to iron-deficiency anemia due to iron loss. This parasite can cause diarrhea also and zinc loss can result through diarrhea

Psychologically demanding situations
Psychologically demanding situation can lead to increased micronutrient requirements [5].

- Physical activities such as exercise - The body uses more energy during physical activities and as a result can lead to a shortage of micronutrients like B vitamins, vitamin C, zinc, iron, etc. If we use micronutrients supplements during these activities then we can boost our energy production and increase our energy levels.

- Menstruation - Blood is lost as a result of menstruation and as a result, there is an increased risk of iron-deficiency anemia due to blood loss. Supplementing with iron can compensate for this loss especially for persons who have a much heavier menstrual flow.

- Defense against pathogens - Supplementing with vitamin C or zinc may reduce the duration and severity of common colds.


Micronutrients have many functions in the human body. They are found in many different foods and beverages (such as smoothies, coconut water and so on). Also, supplements and foods that are fortified with micronutrients are additional sources. Micronutrient deficiency or excess have negative effects on the human body the most extreme being death. We cannot live without these vital nutrients.


1. Womenshealth.gov. 2017. Nutrition basis. [ONLINE] Available at: https://www.womenshealth.gov/fitness-and-nutrition/nutrition-basics. [Accessed 13 September 2017].

2. Rivera-Rodriguez M. K., Rodríguez-Rivera V. A., Roman-Julia R. and Morales-Borges H.R. (2016) Effectiveness of Vitamin C in the Treatment of Anemia in Patients with Chronic Diseases: A Case Study. [ONLINE] Available at: https://www.rroij.com/open-access/effectiveness-of-vitamin-c-in-the-treatment-of-anemia-inpatients-with-chronic-diseases-a-case-study-.php?aid=84029.

3. Maggini S, Maldonado P, Cardim P, Fernandez Newball C, Sota Latino ER (2017) Vitamins C, D and Zinc: Synergistic Roles in Immune Function and Infections. Vitam Miner 6: 167. doi:10.4172/2376-1318.1000167

4. Mazari (2017) Comparision of Response of Oral Versus Injectible Vitamin D in Children Having Rickets. Vitam Miner 6:165. doi: 10.4172/2376-1318.1000165

5. Wishart K (2017) Increased Micronutrient Requirements during Physiologically Demanding Situations: Review of the Current Evidence. Vitam Miner 6: 166. doi:10.4172/2376-1318.1000166