Vitamins And Minerals: Sources, Functions And Signs Of Their Deficiencies; A vitamin is an organic compound, found in food and other natural sources, that our body needs for basic function and health. Many vitamins are available to us in food. For example, citrus fruits are an abundant source of Vitamin C. Other vitamins are present in food but also in other sources. We get Vitamin D by eating fish, eggs, and mushrooms, for example, but exposure to sunlight is also an important source of that vitamin.
Vitamins have three characteristics:
They’re natural components of foods; usually present in very small amounts.
They’re essential for normal physiologic function (e.g., growth, reproduction, etc).
When absent from the diet, they will cause a specific deficiency.
Vitamins are generally categorized as either fat soluble or water soluble depending on whether they dissolve best in either lipids or water.
Vitamins and their derivatives often serve a variety of roles in the body – one of the most important being their roles as cofactors for enzymes – called coenzymes. (See figure below for an example.)
There are 13 essential vitamins:
- Vitamin A
- Vitamin B1 (thiamine)
- Vitamin B2 (riboflavin)
- Vitamin B3 (niacin)
- Pantothenic acid (B5)
- Vitamin B6
- Biotin (B7)
- Folate (folic acid and B9)
- Vitamin B12 (cyanocobalamin)
- Vitamin C
- Vitamin D
- Vitamin E
- Vitamin K
Most minerals are considered essential and comprise a vast set of micronutrients. There are both macrominerals (required in amounts of 100 mg/day or more) and micro minerals (required in amounts less than 15 mg/day).
There are 8 essential minerals:
Vitamins And Minerals: Sources, Functions And Signs Of Their Deficiencies
Vitamin A (Retinol)
Functions: Essential for healthy eyesight, helps with the reproduction of cells, important for immune system function, needed for embryo and fetus development, promotes health of the skin, and also plays a role in healing of wounds and formation of bone.
Signs of Deficiency: Deficiency of vitamin A is a major preventable cause of blindness, an early symptom being night blindness, otherwise known as nyctalopia. Other symptoms are a weakened immune system, dysfunction of the thyroid, and a skin condition known as phrynoderma.
Sources: Chicken and beef liver, eggs, dairy products such as butter, cottage and other whole milk cheeses, whole milk yogurt, and whole milk. Vitamin A can also made in the body from beta-carotene found in dark-green leafy vegetables, carrots, sweet potatoes, pumpkin, apricots, cantaloupe, mangoes and peaches.
Vitamin B1 (Thiamine)
Functions: Important for a healthy metabolism and energy levels, helps with carbohydrate to energy conversion, needed to transform nutrients into ATP, which is used for energy by every cell. Helps to promote healthy heart function, involved in the function of the nervous system and supports the body’s resilience to stress
Signs of Deficiency: Although thiamine deficiency is rare, symptoms include fatigue, depression, irritability, headache, nausea, abdominal discomfort, trouble digesting carbohydrates which can cause a disease called beriberi that results only from severe thiamin deficiency.
Sources: Beef, pork, poultry, organ meats such as liver, whole grains, brown rice, wheat germ, bran, brewer’s yeast, blackstrap molasses, nuts, beans, seeds and spirulina. Grain products such as rice, pasta, bread, and cereal grains are synthetically enriched with thiamine.
Vitamin B2 (Riboflavin)
Functions: Vitamin B2 is an antioxidant, is critical for production of ATP, used for processing fats and amino acids, necessary for a healthy nervous system, skin, liver, eyes and hair. Supplementation may help with the prevention of cataracts, may reduce migraine frequency and length of migraine episodes.
Signs of Deficiency: Redness and swelling of the lining of the throat and mouth, sore throat, sores or cracks in the corners of the mouth and the lips, inflamed and red tongue, skin disorders.
Sources: Organ meats, brewer’s yeast, wild rice, whole grains, almonds, wheat germ, milk, mushrooms, yogurt, soybeans, broccoli, eggs, spinach and brussels sprouts,
Vitamin B3 (Niacin)
Functions: Suppresses inflammation, helps make various sex hormones, helps to improve circulation, helps to metabolize protein and fats, necessary for a healthy nervous system, skin, liver, eyes and hair. Supplementation can improve cholesterol profile, may improve blood sugar control in diabetes, and may be able to decrease symptoms of osteoarthritis.
Signs of Deficiency: Fatigue, poor circulation, depression, indigestion, vomiting, and canker sores. Severe niacin deficiency can result in pellagra, a condition with symptoms that include scaly and cracked skin, diarrhea and dementia.
Sources: Beef kidney, beef liver, tuna, swordfish, salmon, brewer’s yeast, beets, sunflower seeds, and peanuts.
Vitamin B5 (Pantothenic acid)
Functions: Vitamin B5 is needed for breaking down fats and carbohydrates to be used as energy, needed by the body for synthesizing cholesterol, is critical for manufacturing red blood cells, also important for the adrenal gland production hormones related to stress and sex, used for manufacturing the neurotransmitter acetylcholine, and important for the health of the digestive system. Vitamin B5 supplements have been proposed for stress, sports performance enhancement, and treating rheumatoid arthritis.
Signs of Deficiency: Although rare, Vitamin B5 deficiency symptoms can include insomnia, fatigue, depression, vomiting, irritability, burning feet, stomach pains, and upper respiratory infections.
Sources: Although vitamin B5 is found in a wide variety of foods, it’s lost when processed, so fresh foods have more vitamin B5 compared to frozen and canned, or refined food. Good dietary sources of vitamin B5 are cauliflower, corn, brewer’s yeast, kale, tomatoes, broccoli, avocado, lentils, legumes, egg yolks, beef (particularly organ meats like kidney and liver), duck, turkey, chicken, sunflower seeds, peanuts, split peas, soybeans, milk, sweet potatoes, whole-grain breads and cereals, wheat germ, salmon and lobster.
Vitamin B6 (Pyridoxine)
Functions: Vitamin B6 helps with food to glucose conversion, which is made use of for producing energy. It plays a significant part in making neurotransmitters, hormones and proteins. It’s necessary for brain function and development and helps with the manufacture of the mood-influencing hormones norepinephrine and serotonin, as well as the body clock regulating hormone melatonin. It helps control blood levels of homocysteine, a heart disease associated amino acid. Vitamin B6 is needed for vitamin B12 absorption and for the manufacture of immune system cells and red blood cells.
Signs of Deficiency: Although severe vitamin B6 deficiency is rare, studies indicate mild deficiency to be common, especially in the elderly and children. Severe deficiency symptoms include nervousness, muscle weakness, depression, irritability, short-term memory loss and difficulty concentrating.
Sources: Good dietary sources of vitamin B6 include beef liver, turkey, chicken, salmon, tuna, shrimp, cheese, milk, beans, lentils, carrots, spinach, bran, wheat germ, brown rice, whole-grain flour, sunflower seeds and bananas.
Vitamin B7 (Biotin)
Functions: Vitamin B7, formerly called vitamin H, is commonly known as biotin. It’s required for metabolizing energy from food and assisting four enzymes essential for the breaking down of fats, carbohydrates, and proteins. It’s also vital for normal embryonic growth, which makes it an important nutrient in pregnancy. Biotin is also important for the health of the hair, skin and nails.
Signs of Deficiency: Although rare, biotin deficiency symptoms include fatigue, loss of appetite, dry scaly skin, hair loss, magenta colored painful and swollen tongue, cracked mouth corners, dry eyes, depression and insomnia.
Sources: Biotin is found in cooked egg yolks, whole grains, brewer’s yeast, sardines, peanuts, almonds, walnuts, pecans, blackeye peas, beans, soybeans, bananas, mushrooms and cauliflower.
Vitamin B9 (Folate)
Functions: Vitamin B9, otherwise known as folate, helps convert carbohydrates into glucose to be used as energy. Vitamin B9 is important for the function of the brain and plays a part in emotional and mental health. It assists with DNA and RNA production and is especially important in pregnancy, infancy and adolescence when rapid cell growth is taking place. Vitamin B9 and vitamin B12 help with proper red blood cell function. Vitamin B9 also works together with vitamin B12 and vitamin B6 for homocysteine level control, an amino acid associated with heart disease.
Signs of Deficiency: Vitamin B9 deficiency and can result in inflammation of the tongue, gingivitis, poor growth, loss of appetite, forgetfulness, mental sluggishness, diarrhea, shortness of breath and irritability. More folate is needed in pregnancy for reducing neural tube birth defect risk.
Sources: Good dietary sources of folate include brussels sprouts, dark leafy greens, mustard greens, spinach, turnips, asparagus, beets, soybeans, white beans, kidney beans, mung beans, lima beans, brewer’s yeast, beef liver, root vegetables, wheat germ, whole grains, bulgur wheat, milk, orange juice, salmon and avocado.
Vitamin B12 (Cobalamin)
Functions: B12 is an important vitamin for healthy nerve cell maintenance. Vitamin B12 assists with DNA and RNA production. Vitamin B12 and vitamin B9 together help with red blood cell manufacture and also with S-adenosylmethionine (SAMe) production, a compound associated with mood and immune function. Vitamin B12 also works together with vitamin B6 and vitamin B9 for homocysteine level control, an amino acid associated with heart disease.
Signs of Deficiency: Vitamin B12 deficiency is rare in younger individuals, but mild deficiency is not uncommon in older people. Deficiency symptoms include tingling sensation in the toes and fingers, fatigue, nervousness, shortness of breath, numbness, diarrhea, and severe deficiency can result in nerve damage.
Sources: Good dietary sources of vitamin B12 include shellfish and fish, pork, beef, organ meats such as kidney and liver, eggs and dairy products.
Vitamin C (Ascorbic acid)
Functions: Vitamin C is an antioxidant, which helps prevent damage from free radicals. Vitamin C is important for repairing and the growth of the body’s tissues. Vitamin C helps with collagen manufacture, a protein made use of for making blood vessels, cartilage, ligaments, tendons and skin. Vitamin C is required for wound healing, as well as for teeth and bone repair and maintenance.
Signs of Deficiency: Although severe vitamin C is rare, there is evidence to suggest that low vitamin C levels are common. Vitamin C deficiency symptoms include gingivitis, dry hair, dry and scaly skin, easily bruised, slower healing of wounds rate, greater susceptibility to infection, and nosebleeds. A severe deficiency of vitamin C can result in scurvy.
Sources: Good dietary sources of vitamin C include strawberries, blueberries, raspberries, cranberries, oranges, grapefruit, pineapple, red and green peppers, cantaloupe, watermelon, kiwi, papaya, mango, tomatoes, leafy greens, broccoli, Brussels sprouts, cabbage and cauliflower.
Vitamin D (Cholecalciferol)
Functions: Vitamin D works with calcium to help build strong bones as well as maintaining the health of the bones. Vitamin D also helps with regulating the immune system. Lower vitamin D levels are linked to conditions such as depression, high blood pressure, colon, breast, and prostate cancer, and obesity.
Signs of Deficiency: Research indicates that a deficiency in vitamin D is quite common, particularly in the winter months in areas where there is little sunshine. One study suggested that 75% of U.S. adults have low levels of vitamin D. A deficiency of vitamin D can cause rickets in children, a condition that can lead to soft and weak bones.
Sources: Vitamin D is stored in the body which makes it when the skin is exposed to the sun. It can also be found in certain foods, mostly those that are vitamin D fortified, such as milk.
Vitamin E (Tocopherol)
Functions: Vitamin E is an antioxidant, which helps prevent damage from free radicals. Vitamin E helps to make red blood cells. Vitamin E also helps the body to make use of vitamin K.
Signs of Deficiency: Although severe vitamin E deficiency is uncommon, low vitamin D levels are quite common. Symptoms of severe deficiency include loss of muscle mass, problems with vision, muscle weakness, and unsteady walking. Kidney and liver problems can result from long-term deficiency.
Sources: Good dietary sources of vitamin E include wheat germ, cereal grains, sunflower seeds, nuts, eggs, liver, olive oil and some other cold-pressed vegetable oils, spinach, sweet potatoes, yams, avocado and asparagus.
Vitamin K (Phylloquinone)
Functions: Vitamin K is important for blood coagulation (clotting). Vitamin K plays a role in the health of the bones.
Signs of Deficiency: Although a deficiency in vitamin K is rare, it could result in excessive bleeding.
Sources: Good dietary sources of vitamin K include green tea, beef liver, turnip greens, kale, broccoli, cabbage, spinach, dark green lettuce, and asparagus.
Vitamins And Minerals: Sources, Functions And Signs Of Their Deficiencies
Functions: Calcium is important for the growth of, and also the maintaining of strong teeth and bones, and helps in preventing osteoporosis. Calcium helps with muscle, nerve, and heart function.
Signs of Deficiency: Calcium deficiency risk increases as we age and severe symptoms of deficiency include muscle cramps and spasms, brittle nails, memory loss, confusion, depression, bone fractures, tingling or/and numbness of the face, feet and hands.
Sources: Good dietary sources of calcium include brewer’s yeast, blackstrap molasses, cheese, yogurt, milk, tofu, some nuts, cabbage, broccoli, bok choy, kelp, dark leafy greens, sardines, and oysters.
Functions: Chromium is important for the hormone insulin to help with the regulation of blood sugar levels.
Signs of Deficiency: Although chromium deficiency is rare, most diets are low in chromium. Low levels of chromium can result in increased blood sugar, levels of cholesterol, and triglycerides. The risk of some conditions like heart disease and diabetes can also be increased.
Sources: Good dietary sources of chromium are lean meats, brewer’s yeast, cheese, whole grain products, and certain spices.
Functions: Iodine is needed for making thyroid hormones, which are required for normal development and growth.
Signs of Deficiency: Severe deficiency can result in an enlarged thyroid gland. Although iodine deficiency is rare, a deficiency can result in low thyroid hormone levels or hypothyroidism. Symptoms of hypothyroidism include dry skin, weight gain, fatigue, and temperature change sensitivity. In some cases, goiter can develop.
Sources: Good dietary sources of iodine include white deep-water fish, shellfish, kelp, lima beans, soybeans, sesame seeds, garlic, Swiss chard, and spinach. Table salt has iodine added to it as well.
Functions: Iron is found in haemoglobin, a red blood cell protein essential for the transport of oxygen in the blood to the body’s tissues. Iron also plays a part in the production of ATP, the energy source of the body.
Signs of Deficiency: As reported by the WHO, a deficiency in iron is the main nutritional deficiency globally. Iron deficiency can result in anemia. Fatigue and weakness are common anemia symptoms as cells do not get enough oxygen. Children who have iron deficient anemia are at risk of neurodevelopment issues.
Sources: Heme iron (easier absorbed) and non-heme iron are the 2 kinds of iron found in foods. Some dietary sources of heme iron are liver, red meat, shellfish, fish and poultry. Good dietary sources of non-heme iron are legumes, seeds, nuts, whole grains, green leafy vegetables and dark molasses.
Functions: Magnesium is needed by every organ in the body, and also plays a part in the makeup of bones and teeth. Enzymes are activated by magnesium. It contributes to the production of energy. It helps with regulating levels of other necessary nutrients like copper, calcium, potassium, zinc, and vitamin D.
Signs of Deficiency: Although magnesium deficiency is rare, symptoms deficiency include sleep disorders, restless leg syndrome, irritability, anxiety and agitation, abnormal heart rhythms, vomiting, nausea, low blood pressure, muscle cramping, hyperventilation, confusion, seizures, and weak nail growth.
Sources: Dietary sources of magnesium include legumes, tofu, wheat bran, whole grains, blackstrap molasses, spinach and other green leafy vegetables, some nuts, pumpkin, poppy and cumin seeds, oatmeal, bananas, baked potatoes, dark chocolate, coriander, basil, and marjoram.
Functions: Phosphorus together with calcium helps to build strong teeth and bones. Phosphorus helps reduce post-exercise muscle pain. It plays an important part in how energy is used and stored. It helps with the filtering out of waste in the kidneys. It’s needed for tissue and cell growth and repair, as well as for producing RNA and DNA, the genetic building blocks. It helps with regulating levels of other necessary nutrients like iodine, zinc, magnesium, and vitamin D.
Signs of Deficiency: Phosphorus deficiency symptoms include fragile and painful bones, loss of appetite, stiff joints anxiety, irregular breathing, fatigue and irritability. Phosphorus deficiency in children can increase the risk of growth and bone development issues.
Sources: Good dietary sources of phosphorus are meat, fish, poultry, dairy products, eggs, whole grains, garlic, legumes and nuts.
Functions: Potassium is crucial for the proper function of the body’s tissues and cells. Potassium plays an important part in the function of the heart. It also assists with skeletal and smooth muscle contraction, which makes it essential for proper muscular and digestive function.
Signs of Deficiency: Mild potassium deficiency symptoms include leg and arm muscle cramping, fatigue, nausea or vomiting, constipation, bloating, abdominal cramping, excessive urination and/or thirst, low blood pressure fainting, psychosis, depression, and delirium. Severe potassium deficiency is known as hypokalemia.
Sources: Good sources of dietary potassium include citrus, bananas, cantaloupes, avocados, tomatoes, potatoes, lima beans, fish, chicken, and red meat.
Functions: Selenium works as an antioxidant, which helps prevent damage from free radicals. Selenium plays a part in the function of the thyroid. It’s also required for normal immune system functioning.
Signs of Deficiency: Selenium deficiency combined with another stress such as a viral infection can predispose individuals to certain conditions such as Keshan disease. Being deficient in selenium is also associated with infertility in men. It can also play a part in a form of osteoarthritis known as Kashin-Beck disease, and can also aggravate iodine deficiency.
Sources: Good dietary sources of selenium include wheat germ, brewer’s yeast, liver, fish such as tuna, mackerel, halibut, herring and flounder, shellfish such as lobster, scallops and oysters, butter, whole grains, garlic, Brazil nuts and sunflower seeds