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Essential Elements for Life


There are about 118 sorted by atomic number in the Periodic Table. 94 out of these 118 elements are considered as natural elements, and 20 to 25% of them are known as “essential to life.” These essential elements are quite similar among organisms but vary from species to species (e.g., humans need 25 elements while plants need only 17). 

But what characteristics make an element “essential”

By definition, an element is considered essential if a deficiency impacts the normal functioning of an organism and causes defective development, improper functioning, or particular diseases. 

Essential elements are identified within 3 subgroups which are the following:

  1. Major Elements – also referred to as Bulk Elements (O, C, H, N);
  2. Major Minerals – also referred to as Macrominerals (Ca, P, K, N, S, Mg, Cl);
  3. Trace Elements – present in minimal amounts (Fe, I, Cu, Zn, Mn, Co, Cr, Se, Mo, F, Sn, Si, V).

All 3 of the subgroups, along with the corresponding essential elements, will be discussed throughout the rest of the article.

Major (Bulk) Elements

Living organisms primarily consist of major (also referred to as bulk) elements, which are the following: Oxygen (O), Carbon (C), Hydrogen (H), and Nitrogen (N). These 4 elements comprise approximately 99.3% of total atoms in the human body and makeup 96% of living matter. They constitute the basic structure of all biochemical molecules and our organs, as well as muscles. Along with that, these elements are also essential for our everyday diet. 

If we take a typical healthy human body, the bulk element composition (percentage of atoms in the body) would be the following:

  • Hydrogen (H) – 63.0% - essential component of organic molecules and water, the basis of all body fluids and acids.
  • Oxygen (O) – 24.2% - constituent of organic molecules and water, a crucial element to the body’s use of energy.
  • Carbon (C) – 10.5% - key element in organic molecules.
  • Nitrogen (N) – 1.35% - key constituent of proteins

Major Minerals (Macrominerals)

Major minerals, or macrominerals, are elements that provide essential ions in body fluids as well as constitute primary structural components of the body. They include Calcium (Ca), Phosphorus (P), Potassium (K), Sodium (Na), Sulfur (S), Magnesium (Mg), and Chlorine (Cl), which make up approximately 0.7% of total atoms. Since these elements have quite a similar function as vitamins, they are usually referred to as “trace vitamins.” 

Specific macromineral plays its role in various processes, including but not limited to fluid balance, strengthening bones or teeth, proper functioning of the nervous system, and muscle contraction. The major minerals are part of our healthy balanced diet, but also, they are accessible as dietary supplements. 

The major minerals include the following:

  • Calcium (Ca) – commonly known for the maintenance of healthy bones and teeth, but in reality, it is responsible for many more processes, such as blood clotting, proper functioning of the nervous system and muscles, regulation of heartbeat, digestive system.

- Common sources of Calcium – dairy products (milk, cheese, yogurt, etc.), nuts, green leafy vegetables (cabbage, broccoli), cereal, soya beans, tofu, products made with fortified flour, fish that you eat with bones (sardines, pilchards).

- Problems with Calcium deficiency – symptoms and disorders are provided in the table below:



  • Muscle aches, cramps, spasms;
  • Pain in thighs and arms when moving;
  • Numbness and tingling in hands, arms, feet, legs, and around the mouth.


  • Extreme fatigue, lethargy, a feeling of sluggishness, lack of energy;
  • Insomnia, sleepiness;
  • Lightheadedness, dizziness, lack of focus, forgetfulness, confusion.

Nail and Skin Problems

  • Skin becomes dry and itchy;
  • Eczema – skin inflammation. Highly treatable;
  • Psoriasis – cells build up on the surface of the skins, and extra cells form scales, red patches. Causes itchiness and pain. There is no cure;
  • Dry, broken, brittle nails;
  • Alopecia – hair fall in round patches.


  • Reduces the mineral density of bones. Might lead to Osteoporosis (bones become thinner and more fractures).

Dental Problems

  • Weak roots, irritated gums, brittle teeth, decay.

- Problems with excess intake of Calcium – stomach pain and diarrhea.

  • Phosphorus (P) – commonly known for bone growth and normal functioning of the cell membrane. Phosphorus, which is stored in bones and teeth, plays a role in the conversion of the food into energy.

    - Common sources of Phosphorus – found in food high in proteins (dairy products, meat, beans, lentils, nuts, grains).
    - Problems with Phosphorus deficiency – Phosphorus deficiency is quite uncommon since even if you do not get enough of Phosphorus, your body can still compensate the mineral through reabsorbing already existing Phosphorus. Phosphorus deficiency might become a problem in case if you are deficient in other vitamins that help the absorption of Phosphorus. Some conditions that might lead to Phosphorus deficiency are the following: diabetes, alcoholism, anorexia, inherited disorders.

  • Potassium (K) – responsible for the normal functioning of the nervous system, muscle contraction, normal heart rate. It is an essential constituent of phospholipids and ATP. Potassium is also a common electrolyte. Plays a role in the coregulation of ATP along with Sodium.

    - Common sources of Potassium – bananas, oranges, cantaloupe, apricots, grapefruit, dried fruits, potatoes, mushrooms, peas, cucumbers, milk, meat, nuts.
    - Problems with Potassium deficiency – low potassium level is referred to as hypokalemia, which can cause arrhythmias or respiratory failure.

  • Sodium (Na) – responsible for blood pressure regulation. Works in complex with chloride for maintenance of fluid balance out of the cells. Similarly to Potassium, Sodium is also a common electrolyte. Plays a role in coregulation of ATP along with Potassium.

    - Common sources of Sodium – table salt (NaCl), processed food that contains salt.
    - Problems with Sodium Deficiency – quite rare (might cause muscle cramps). Intake of excess Sodium is much more problematic, which might cause elevated blood pressure.

  • Sulfur (S) – an important component of some amino acids and proteins. A constituent of various co-enzymes. Some organisms oxidize sulfur for energy conversion (production of ATP). Is considered as a sole energy source for several lithotrophic bacteria and archaea. Sulfur is also essential for antibacterial effects, which promotes skin loosening and shedding. Moreover, sulfur plays a vital role in the synthesis of particular proteins in the body.

    - Problems with Sulfur deficiency – joint pain, certain diseases.

  • Magnesium (Mg) – essential for the control of biochemical functions, such as muscle contraction, nerve impulses, the sugar level in the blood, blood pressure regulation, maintenance of strong bones.

    - Common sources of Magnesium – nuts, seeds, whole grains, dark green vegetables, legumes, yogurt, salmon, cereal, bananas, potatoes.
    - Problems with Magnesium deficiency – usually cause gastrointestinal diseases, including but not limited to Crohn’s disease, celiac disease, alcohol abuse, diabetes.
  • Chlorine – utilized by your body to produce gastric juices. Found along with Sodium in body fluids outside the cells. Functions as a cellular pump.

    - Common sources of Chlorine – table salt, vegetables (seaweed, rye, tomatoes, lettuce, celery, olives).

Trace Elements

Trace elements are present in low amounts (comprise less than 0.01% of total atoms) in a living organism. Even though, they are significant for health and proper functioning. Several elements (Selenium and Chromium) are also toxic and might cause cancer, but they are still considered as essential elements for life. This is because the chemical form of an element impacts on its toxicity; So, various compounds composed of Selenium or Chromium might be toxic while others might constitute mineral supplements. Obviously, the toxicity of an element is dependent on the amount of intake, as well. 

Due to the low levels of trace elements, it is quite hard to detect them. Therefore, there are about 13 trace elements identified nowadays, which are the following:

  • Iron (Fe) – the most critical trace element since it is a part of haemoglobin which functions as an oxygen carrier from lungs through the whole body. Iron is also an essential constituent of lots of proteins, enzymes, and catalysts. Deficiency results in anemia (symptoms: weakness, pale skin, lack of concentration). People deficient in Iron are now allowed to donate blood.
  • Iodine (I) – necessary for the production of thyroid hormones (in Thyroid Gland), which are essential for bone and brain development of infants. Iodine deficiency causes Goitre (swelling of the Thyroid Gland). Common sources of Iodine are iodized salt, drinking water (in some countries), milk (cow), marine plants.
  • Copper (Cu) – an important constituent of redox enzymes and catalysts. Plays a role in red blood cell formation along with Iron. Controls the maintenance of bones, blood vessels, nerves, immune system. It is essential for the prevention of cardiovascular diseases and osteoporosis. Deficiency might cause anemia.
  • Zinc (Zn) – very important for the proper functioning of our immune system. Identified as a constituent of many enzymes and catalysts. Essential for appropriate cell division, growth, wound healing, the breakdown of carbohydrates, sensation of smell/taste. Zinc deficiency might lead to poor growth rate.
  • Manganese (Mn) – a great contributor to the metabolism of various compounds (e.g., amino acids, carbohydrates, cholesterol, glucose). Has a positive impact on blood clotting, proper bone formation, and reduces inflammation. It is commonly known as a constituent of different co-factors.
  • Cobalt (Co) – enhances vitamin B12 absorption. Helps the treatment process of anemia and other infectious diseases and the formation of haemoglobin.
  • Chromium (Cr) – aids different processes, including the breakdown of fats and carbohydrates. Plays an important role in the synthesis of fatty acids and cholesterol.
  • Selenium (Se) – plays a role in the production of specific proteins (antioxidant enzymes). Prevents cells from damage and poisonous impact of heavy metals and other dangerous substances. Deficiency might cause pernicious anemia.
  • Molybdenum (Mo) – important for enzyme activation and the breakdown of harmful substances (especially sulfites). Prevents toxins from building up in the body. Deficiency impacts the growth rate. 
  • Fluorine (F) – plays a role in the maintenance and strengthening of bones. Prevents teeth decay. Deficiency might cause dental decay, damage the kidney, bones, nerves, muscles, or cause osteoporosis.
  • Tin (Sn) – does not have any essential functions, but deficiency might result in poor growth rate.
  • Silicon (Si) – silicon is very important for treatment of many diseases, including but not limited to osteoporosis, heart disease, stroke, Alzheimer’s disease, digestive system disorders, hair loss, improvement of hair and nail quality. It can also enhance wound healing.
  • Vanadium (V) – useful for prediabetes and diabetes. Also, necessary for the control of low levels of sugar, high levels of cholesterol, or lipids. Deficiency might result in poor growth rate. 


Major Elements
Major Minerals

Trace Elements
















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