Micronutrients are the essential vitamins and minerals required by any living entity, it supplements the major nutrients like protein, carbohydrate and fat and helps in regulating mental and physical wellbeing of any living organism. The essential vitamins are Vitamin A, B, C, D, E and K and minerals are calcium, phosphorous, magnesium, chloride, sodium, potassium, sulphur, iron, manganese, copper, zinc, iodine, fluoride and selenium.

Types of Micronutrients

Water-Soluble Vitamins:

These are the vitamins which dissolves in water and easily flushed out from the body in case of excessive consumption. These vitamins are difficult to store in body for later use, hence regular consumption of required amount is needed to maintain its balance in body. The water-soluble vitamins along with their functions are provided in Table 1.

Table 1

Vitamins
Functions
Vitamin B1 (Thiamine) Converts Nutrients into Energy
Vitamin B2 (Riboflavin) Essential for cell function and metabolism
Vitamin B3 (Niacin) Converts food into energy
Vitamin B5 (Pantothenic Acid) Essential for fatty acid synthesis
Vitamin B6 (Pyridoxine) Releases sugar from stored carbohydrates and create red blood cells
Vitamin B7 (Biotin) Metabolism of fatty acid, amino acids and glucose
Vitamin B9 (Folate) Important for cell division
Vitamin B12 (Cobalamin) Necessary for red blood cell formation, neural system and brain functioning
Vitamin C (Ascorbic Acid) Formulation of neurotransmitters and collagen

The above table illustrates the necessary function of water-soluble. The functions mentioned are highly important for maintaining the individual health and require regular consumption of vitamin rich diets. The source of these vitamins and their recommended daily allowances (RDA) for an adult are summarised in Table 2.

Table 2

Vitamins
Source
RDA for an Adult
Vitamin B1 (Thiamine) Whole grain, fish, meat, beef, liver, dried milk, nuts, oats, oranges, pork, eggs, seeds, legumes, peas and yeast 1.1-1.2 mg
Vitamin B2 (Riboflavin) Organ meats, egg, milk, asparagus, broccoli, and spinach 1.1-1.3 mg
Vitamin B3 (Niacin) Meat, salmon, leafy veggies, beans, fish, chicken, turkey, pork, beef, mushrooms, brown rice, peanuts, avocados, green peas, 14-16 mg
Vitamin B5 (Pantothenic Acid) Organ meats, mushrooms, beans, peas, lentils, nuts, dairy products, tuna, avocado 5 mg
Vitamin B6 (Pyridoxine) Fish, pork, milk, whole grain cereals, eggs, veggies, soybeans, carrots, potatoes 1.3 mg
Vitamin B7 (Biotin) Egg, almonds, spinach, sweet potatoes, walnuts, peanuts, cereals, milk, salmon, pork, sardines, mushroom, cauliflower 30 mcg
Vitamin B9 (Folate) Beef, liver, black-eyed peas, spinach, asparagus, turnip greens, romaine lettuce, brussels sprouts, broccoli, nuts beans, whole grain, sea food 400 mg
Vitamin B12 (Cobalamin) Clams, fish, meat, poultry, eggs, milk, milk products 2.4 mcg
Vitamin C (Ascorbic Acid) Citrus fruits, bell peppers, brussels sprouts, spinach, cabbage, tomato juice, broccoli 75-90 mg

Fat-Soluble Vitamins:

Apart from water-soluble nutrients, human body requires some other vitamins which are soluble in fat rather than water. These nutrients are stored in liver and fatty tissues for future use. The best way to consume these nutrients are along with fat rich food in order to have desired effects. Some of the fat-soluble nutrients along with their essential functions are provided in Table 3.

Table 3

Vitamins
Functions
Vitamin A (Retinol) Essential for healthy eyesight and organ functions
Vitamin D (Ergocalciferol) Boost immunity and acts as catalyst for calcium absorption and bone growth
Vitamin E (Tocopherol) Supports immune functionality and protects cell damage
Vitamin K  Blood clotting and bone development

The above table illustrates the necessary function of fat-soluble. These nutrients are stored in our fatty tissues and liver for future consumption. In order to avoid any detrimental effects due to long exposure we need to consume the nutrients in recommended daily allowances (RDA) limits as prescribed in Table 4 for an adult.

Table 4

Vitamins
Source
RDA for an Adult
Vitamin A (Retinol) Liver, dairy, fish, carrots, spinach, sweet potatoes, dairy products, broccoli 700-900 mcg
Vitamin D (Ergocalciferol) Salmon, tuna, mackerel, sunlight, fish oil, milk, cheese 600-800 IU
Vitamin E (Tocopherol) Sunflower seeds, wheat germs, nuts, spinach, broccoli 15 mg
Vitamin K  Leafy veggies, Fish, liver, meat, eggs, soybean, pumpkin, brussels sprout, broccoli, cabbage, cauliflower 90-120 mcg

Macro Minerals:

The nutrients required in relatively larger quantity than other minerals and in lesser quantity than macronutrients. Every mineral has very specific role to perform in proper functioning of the body. Any short of imbalance may lead to life-threatening health condition.  The essential macro minerals and their specific functions are provided in Table 5.

Table 5

Minerals
Functions
Sodium Act as electrolyte, fluid balance, maintains blood pressure
Magnesium Regulates blood pressure
Phosphorus Bone and cell membrane structure
Sulphur Quintessential to every living tissue, present in amino acids like methionine and cysteine 
Chloride Fluid balance and regulates digestive juice formation 
Potassium Act as electrolyte, fluid balance, helps in nerve transmission and muscle function
Calcium Functioning of bone and teeth, muscle function, blood vessel contraction

The above table illustrates the essential functionality of macro minerals. These nutrients should be part of our daily diet otherwise we need to have supplements for proper functioning of the body. The recommended daily allowance of macro minerals is provided in Table 6.

Table 6

Minerals
Source
RDA for an Adult
Sodium Salt, canned and processed food, sunflower seed, clams 2300 mg
Magnesium Almond, cashew, black beans, avocado, whole grain, fatty fish, legumes 310-420 mg
Phosphorus Salmon, yogurt, milk and milk products, meat, beans, lentils nuts 700 mg
Sulphur Meat, poultry, fish, seafood, legumes, onion, garlic, sprouts, egg No Consensus
Chloride Seaweed, salt, celery, rye, tomatoes, lettuce, olives 1800-2300 mg
Potassium Lentils, banana, oranges, grapefruit, apricots, prunes, raisins, dates, mushroom, spinach, broccoli 4700 mg
Calcium Milk products, cheese, leafy veggies, soybeans, tofu, sardines, pilchards 2000-2500 mg

Trace Minerals:

In addition to macro minerals and essentials vitamins, we need some of the minerals in trace amount. Although the required dosages are very minimal, but these are very essential for proper functioning of body and mind. Some of the trace minerals along with their main functionality in Table 7.

Table 7

Minerals
Functions
Fluoride Essential for bone and teeth development
Manganese Helps in protein, carbohydrates and fat metabolism
Iron Oxygen supply to muscles and formulation of certain hormones
Copper Brain and nervous system functioning
Zinc Normal growth, immune functioning and wound healing 
Selenium Essential for thyroid health and reproduction
Iodine Thyroid regulation

The above table 7 summarised the functioning of trace minerals. These minerals help in maintain the normal functioning of the body. Owing to the trace amount of requirement, people should not ignore its importance in maintaining mental and physical health. The recommended daily intake of these trace minerals for an adult is summarised in Table 8.

Table 8

Minerals
Source
RDA for an Adult
Fluoride Fruit juice, crab, water, shellfish, grapes 3-4 mg
Manganese Pineapple, peanuts, whole grains, clams, oysters, mussels, nuts, soybeans, legumes, rice, leafy vegetables, coffee, tea, black pepper 1.8-2.8 mg
Iron Oyster, white beans, spinach, lentils, tofu, cashews, whole grain 8-18 mg
Copper Liver, crab, oyster, mushrooms, lobster, leafy veggies, nuts 900 mcg
Zinc Whole grain, oyster, crab, red meat, poultry, nuts, chickpeas 8-11 mg
Selenium Nuts, sardines, ham, pork, beef, turkey, chicken, fish, shellfish, and eggs 55 mcg
Iodine Seaweed, shrimp, fish, Cod, dairy products,  whole grain 150 mcg

The name micronutrients itself indicates about the required intake of these nutrients. However, its importance should not be overlooked as these nutrients have very important role in proper functioning of body. We should include nutrient rich food in our diet with at least five servings of veggies and fruits as recommended by World Health organisation (WHO).