Micronutrients are essential for carrying out bodily functions, but the body requires them in trace amounts. All the thirteen vitamins and sixteen minerals fall under the essential micronutrients. These elements are needed in much smaller amounts than the macronutrients. Often, micronutrients work together.1
Excess or deficiency usually causes nagging and chronic problems.
Vitamins: Vitamins are essential organic compounds that are needed for growth, repair, digestion, metabolism, nervous system functioning, vision maintenance, blood clotting, and immunity. The lipid/fat soluble vitamins are vitamin A, D, E, K and the water-soluble vitamins are vitamin C and all the B vitamins (thiamine, riboflavin, niacin, pantothenic acid, pyridoxine, biotin, folate, and cobalamin). One of most crucial activities of vitamins is their function as co-enzymes. Vitamin B3 (niacin) is involved in the electron transport mechanism during ATP formation.
Fat soluble vitamins are stored in lipid bi-layer cell membranes and in adipose tissues. They are not needed in the diet every day as they are available in fatty tissues. On the other hand, water soluble vitamins are needed more often from diet since they can be excreted with water.
Minerals are the basic elements and do not require breaking down further to be absorbed, minerals survive storage and cooking. Electrolytes like sodium and potassium are required for fluid balance in the body, calcium is the most important mineral for bones and muscles. The need for micronutrients depends upon age, sex, body build, medications, activity, pregnancy, illness, injury, etc.
Vitamins, Functions, Source:
Vitamin | Function | Source |
Thiamine (vitamin B1) | Co-enzyme needed for energy metabolism, important for nerve function. | Found in all nutritious foods in moderate amounts: beef, whole grain or enriched breads and cereals, legumes, nuts, and seeds. |
Riboflavin (vitamin B2) | Co-enzyme needed for energy metabolism, important for normal vision and skin health. | Milk and milk products; leafy green vegetables; whole grain or enriched breads and cereals. |
Niacin (vitamin B3) | Co-enzyme needed for energy metabolism; important for nervous system, digestive system, and skin health. | Meat, poultry, fish, whole grain or enriched breads and cereals, vegetables (especially mushrooms, asparagus, and leafy green vegetables), peanut butter. |
Pantothenic acid (vitamin B5) | Co-enzyme needed for energy metabolism. | Widespread in foods. |
Biotin (vitamin B7) | Co-enzyme needed for amino acid and fatty acid metabolism | Widespread in foods; also produced in intestinal tract by bacteria. |
Pyridoxine (vitamin B6) | Co-enzyme for amino acid synthesis assistance; helps make red blood cells. | Meat, fish, poultry, vegetables, fruits. |
Folate (folic acid, B9) | Co-enzyme needed for making DNA and new cells, especially red blood cells. | Leafy green vegetables and legumes, seeds, orange juice, and liver; now added to most refined grains. |
Cobalamin (vitamin B12) | Co-enzyme needed for making new cells, especially RBC; important for nerve function. | Meat, poultry, fish, seafood, eggs, milk and milk products; not found in plant foods. |
Ascorbic acid (vitamin C) | Antioxidant; Co-enzyme needed for protein metabolism; collagen synthesis, immune system health; aids in iron absorption. | Found only in fruits and vegetables, especially citrus fruits, vegetables in the cabbage family, cantaloupe, strawberries, peppers, tomatoes, potatoes, lettuce, papayas, mangoes, kiwifruit. |
Vitamin | Function | Source |
Vitamin A (and its precursor*, beta-carotene) [*A precursor is converted to the vitamin by the body.] | Needed for vision, reproduction, healthy skin and mucous membranes, bone and tooth growth, immune system health. | Vitamin A from animal sources: Fortified milk, cheese, cream, butter, fortified margarine, eggs, liver. Beta-carotene (from plant sources): Leafy, dark green vegetables; dark orange fruits (apricots, cantaloupe) and vegetables (carrots, winter squash, sweet potatoes, pumpkin). |
Vitamin D | Needed for proper absorption of calcium; stored in bones and teeth. | Egg yolks, liver, fatty fish, fortified milk, fortified margarine. When exposed to sunlight, the skin can make vitamin D. |
Vitamin E | Antioxidant; protects cell walls. | Polyunsaturated plant oils (soybean, corn, cottonseed, safflower); leafy green vegetables; wheat germ; whole grain products; liver; egg yolks; nuts and seeds. |
Vitamin K | Needed for proper blood clotting. | Leafy green vegetables (kale, collard greens, and spinach); green vegetables (broccoli, Brussels sprouts, and asparagus); also produced in the intestinal tract by bacteria. |
Minerals: Minerals are solid inorganic substances that form crystals and are classified depending on the amount needed by the body. Trace minerals, such as molybdenum, selenium, zinc, iron, and iodine, are only required in small amounts, typically a few milligrams or less.4
There are sixteen essential minerals and thirteen essential vitamins, each with major functions in the body (Table- 3, 4). Minerals can be classified into two types.
- Macro minerals: These are required in large quantities and include calcium, phosphorus, magnesium, sodium, potassium, chloride, and sulfur.
- Micro minerals: These are required in small quantities and include iron, manganese, copper, iodine, zinc, cobalt, fluoride, and selenium.5
Minerals, Major Functions and Source:
Macro Minerals | ||
Mineral | Function | Sources |
Sodium | Fluid balance, nerve transmission, and muscle contraction. | Table salt, soy sauce; large amounts in processed foods; small amounts in milk, breads, vegetables, and unprocessed meats. |
Calcium | For healthy bones and teeth, helps muscles relax and contract; important for nerve functioning, blood clotting, blood pressure. | Milk and milk products; canned fish with bones (salmon, sardines); fortified tofu and fortified soy beverage; greens (broccoli, mustard greens); legumes. |
Chloride | Needed for proper fluid balance, stomach acid. | Table salt, soy sauce; large amounts in processed foods; small amounts in milk, meats, breads, and vegetables. |
Magnesium | Found in bones; needed for making protein, muscle contraction, nerve transmission, immune system health. | Nuts and seeds, legumes, leafy green vegetables, seafood, chocolate, artichokes, “hard” drinking water. |
Phosphorus | Important for healthy bones and teeth; found in every cell; part of the system that maintains acid-base balance. | Meat, fish, poultry, eggs, milk. |
Potassium | Needed for proper fluid balance, nerve transmission, heart muscle function, and muscle contraction. | Meats, milk, fresh fruits and vegetables, whole grains, legumes. |
Sulfur | Found in protein molecules. | Occurs in foods as part of protein: meats, poultry, fish, eggs, milk, legumes, nuts. |
Minerals, Major Functions and Source:
Mineral | Functions | Sources |
Iron | Needed to make heme of hemoglobin in red blood cells that carries oxygen in the body; needed for energy metabolism. | Organ meats, red meats, fish, poultry, shellfish (especially clams), egg yolks, legumes, dried fruits, dark leafy greens, iron-enriched breads and cereals, and fortified cereals. |
Zinc | Part of many enzymes; needed for protein and DNA production; has a function in taste perception, wound healing, normal fetal development, production of sperm, normal growth and sexual maturation, immune system health. | Meats, fish, poultry, leavened whole grains, vegetables. |
Chromium | Works closely with insulin to regulate blood sugar (glucose) levels. | Liver, brewer’s yeast, whole grains, nuts, cheeses. |
Copper | Part of many enzymes; needed for iron metabolism. | Legumes, nuts and seeds, whole grains, organ meats, drinking water. |
Fluoride | Involved in formation of bones and teeth; helps prevent tooth decay. | Drinking water (either fluoridated or naturally containing fluoride), fish, and most teas. |
Iodine | Found in thyroid hormone, which helps regulate growth, development, and metabolism. | Seafood, foods grown in iodine-rich soil, iodized salt, bread, dairy products. |
Manganese | Part of many enzymes. | Widespread in foods, especially plant foods. |
Molybdenum | Part of some enzymes. | Legumes, breads and grains, leafy greens, leafy green vegetables, milk, liver. |
Selenium | Antioxidant | Meats, seafood, grains. |
Other essential trace minerals are nickel, silicon, vanadium, and cobalt.2,6
Fluid Balance in the Body:
Water makes up two-thirds of our body, about 55-60%; in babies it is about 75%. It is compartmentalized into intracellular fluid and extracellular fluid. The brain and heart are composed of 73% water, lungs are 83% water, skin is 64% water, muscles and kidneys are 79%, bones are 22% water, blood is 83% water, and eyes are 95% water.7,8
Fig-1: Fluid distribution in the human body9
Functions of Water in Body:
- All nutrients are transported in blood and lymph.
- It is a building material of all cells.
- All macronutrients are broken down and metabolized with water.
- Flushes all toxic and waste elements from the body.
- It is the shock absorber for brain, spinal cord, and fetus.
- Forms saliva lubricates synovial joints.
- Is the temperature regulator.
- It is a source of minerals.
- Is the catalyst that speeds up enzymatic reactions.8
Fluid balance depends on how much fluid we intake, how much is lost. Depending on the body’s activity fluid need goes up or down. We take in fluids from drinking water and other beverages, skin also absorbs water. Water is lost from the body from breathing, sweating, exercise, with urine and feces. A basic calculation of fluid need: for every kilogram of body weight 30-40 ml of water is needed.10 Book pg 266. With age, total body water content diminishes. By the age of eighty, a person only has 45% of water content in their body.9
Fluid and Electrolyte Balance:
The body fluid has all the elements dissolved in it that are transported throughout the body. Cells, proteins, glucose, lipoproteins, electrolytes, are all carried within the body fluid.9
The charged minerals are the electrolytes (mainly used in diagnostics- NA+, K+, Cl–, HCO3–), they are the particles that balance the osmotic pressure of body fluid which guides the movement of water in and out of the cells. Electrolyte balance is one of the most important functions as it balances the total fluid in the body (excess fluid causes fluid overload, less leads to dehydration) to maintain homeostasis.9
Electrolytes are also involved in- maintaining the pHvalue through acid-base balance (better for body to be more alkaline), moving nutrients into the cell, removing waste product from the cells, maintaining blood pressure and cardiac rhythm, generating synaptic impulses of nervous system, keeping the bones and teeth healthy, etc. Electrolytes are all sourced from food and drinks that we take. When for any reason there is water imbalance in the body, it leads to electrolyte imbalance. The important electrolytes, their main functions and imbalances are:
Electrolytes | Functions | Imbalance |
Bicarbonate | Acid-base balance to maintain pH. Moves CO2 along the bloodstream. | Low HCO3 causes acidosis and high HCO3 cause alkalosis |
Calcium | Bones and Teeth mineral | Low- Hypocalcemia High- Hypercalcemia |
Chloride | Controls amount of fluid in the body, responsible for blood volume and blood pressure. | Low- Hypochloremia High- Hyperchloremia |
Magnesium | Regulates muscle, nerves, and heart function along with blood pressure and blood glucose level. | Low- Hypomagnesemia High- Hypermagnesemia |
Phosphate | Work with calcium to make bones and teeth strong | Low-Hypophosphatemia High- Hyperphosphatemia |
Potassium | Maintain cardiac rhythm, control cells and muscles to work properly, maintains blood pressure. Potassium is more intracellular. | Low- Hypokalemia High-Hyperkalemia Both cause life threatening cardiac arrythmia. |
Sodium | Balances fluid in the body, more extracellular, regulates blood pressure, blood volume and makes cell and muscles work properly. | Low- Hyponatremia High- Hypernatremia Hyponatremia causes muscle weakness, confusion, seizures. Hypernatremia may cause same symptoms. |
Electrolyte imbalances are easily diagnosed from electrolyte panel testing. Usually, diet helps alleviate mild electrolyte imbalance. However, in more serious cases if there are low electrolytes it is compensated with medicines and intravenous iso or hypertonic fluids. Too much electrolyte due to any medical condition requires flushing from the system and a dialysis may be indicated.11
Role of Nutrients, Fluid and Electrolytes:
Nutrition plays a crucial role in health and development as it serves one or more of three basic functions: providing energy, contributing to body structure, and/or regulating chemical processes in the body. Improved nutrition is associated with better infant, child, and maternal health, stronger immune systems, safer pregnancy and childbirth, reduced risk of non-communicable diseases such as diabetes and cardiovascular disease, and increased longevity. No single nutrient can be compromised. Consuming excessive macronutrients will have no benefit without the presence of the micronutrients as all chemical reactions in the body are dependent on these vitamins and minerals. Fluid remains the main vehicle to carry all nutrients all through the body.
Author of this article
Dr. Maliha Mannan Ahmed, MBBS (BMC), MBA (ULAB), Masters in Healthcare Leadership (Brown University, USA) and Level 1 Certification on Precision Nutrition.
The Executive Editor of The Coronal.
Reference:
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