You may hear the word “vitamin” thrown around here and there. But what does it actually mean? The word “vitamin” originally comes from the phrase “vital amines,” amines being an organic group that every amino acid, the basic building blocks of protein, consists of, although many vitamins actually do not contain amines. According to Britannica, a vitamin is “any of several organic substances that are necessary in small quantities for normal health and growth in higher forms of animal life.” Essentially, vitamins are organic substances that you need for normal growth, normal cell function, metabolism, and health. They act as cofactors in metabolic processes that help enzymes carry out metabolic reactions. They support immunity, strengthen the bones, maintain skin and eye health, and convert food into energy.
There are 13 essential vitamins, aka vitamins that you need to get through food sources: A, B complex, C, D, E, and K. They are named by letters as they were discovered. There are missing letters because some vitamins were reclassified. For example, vitamin F was reclassified as essential fatty acids, and vitamin G was reclassified as B2. So, what does each vitamin do, and what foods contain each vitamin?
Vitamin A helps the immune system work to fight disease and infection, keeps our skin healthy, helps with vision, and helps with reproduction and growth. Vitamin A can be found in orange and yellow fruits and vegetables, such as carrots, mangoes, and sweet potatoes. You can also find it in some leafy greens such as spinach, peas, and broccoli. Some animal sources include liver, eggs, and certain dairy products. If you don’t get enough vitamin A, aka vitamin A deficiency, you can have an increased risk of infections, night blindness and permanent vision loss, and an excessive build up of keratin of the skin. This is one of the most common vitamin deficiencies, so it may be best to evaluate if vitamin A is something you lack.
Vitamin B was thought to be one vitamin. However, over time, scientists discovered that “vitamin B” actually contains 8 different types of vitamins. That’s why often instead of only saying vitamin B, we say vitamin B complex or B-group vitamins. The 8 types of B-group vitamins are thiamin (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), biotin (B7), folate or ‘folic acid’ (B9), and cyanocobalamin (B12). Some B-group vitamins help our bodies use carbohydrates, lipids, and protein for energy, and some help cells make new DNA to multiply cells. Foods that contain B-group vitamins are lean meat (high protein, low fat meats), fish, whole grains, fruits, vegetables, and legumes. B-group vitamin deficiency can lead to many different problems, depending on the vitamin. For example, vitamin B12 deficiency can lead to fatigue, weakness, loss of appetite, headaches, vision problems, irritability, and many more. There are just so many different symptoms of B-group vitamin deficiency due to the variety of vitamins that it can be in its own article.
Vitamin C, aka ascorbic acid whose name originates from the condition scurvy (a for no/not and scorbutus, Latin for scurvy), helps with collagen production, which is needed to strengthen the skin, blood vessels, and bone and helps to repair wounds and the skin. Metabolic processes can create free radicals, molecules that contain at least one unpaired electron, which can damage cells and can contribute to chronic diseases and aging. Antioxidants, such as vitamin C, can destroy free radicals by donating an electron to the unpaired electron, allowing it to become paired. Vitamin C also helps with iron absorption from plants, the immune system, and the production of neurotransmitters, which help the brain operate. As vitamin C can be lost due to heat, it is best to eat raw foods for the consumption of vitamin C. Sources of vitamin C include citrus fruits, mangoes, kiwis, cabbage, spinach, lettuce, and broccoli. As the origin of the scientific name of vitamin C may entail, vitamin C cured scurvy. Naturally, the deficiency of vitamin C can lead to scurvy. Symptoms of scurvy include fatigue, loss of appetite, nausea, diarrhea, fever, painful joints and muscles, and bleeding around hair follicles on the skin.
Vitamin D helps with strong bones and muscles. Your main source of vitamin D is the sun, and you need vitamin D to be able to use calcium, which is important for your bones and for certain metabolic processes overall. Some food sources of vitamin D, which sources about 5-10% of your vitamin D, include fatty fish, eggs, and fortified milk. As vitamin D is necessary to use calcium, vitamin D deficiency may lead to osteoporosis, more frequent falls, bone fractures, and rickets, in children.
Vitamin E is an antioxidant like vitamin C. It helps protect the body from free radicals, which also includes those from exposure to cigarette smoke and radiation. Vitamin E helps with our vision, immune system, and skin. Although not to the degree as vitamin C, vitamin E can also be lost due to heat, so it’s best to consume food sources in its fresh form, except when you should cook it, like meats and eggs. Sources of vitamin E include meats, particularly the liver, egg yolks, spinach, broccoli, nuts, seeds, and oils, such as extra virgin, sunflower, and soybean. Vitamin E deficiency is rare, but it doesn’t mean it doesn’t happen. It can happen with people with certain diseases that cause fat malabsorption such as cystic fibrosis. Vitamin E deficiency symptoms tend to be related to the nervous system. Symptoms include muscle weakness, vision issues, slow reflexes, and trouble walking. Other symptoms include numbness, fatigue, and a weakened immune system.
The last essential vitamin, vitamin K, helps with healthy bones, blood clotting, and wound healing. Food sources of vitamin K include spinach, kale, avocado, kiwi, and soybean oil. Like vitamin E, vitamin K deficiency is rare. It can happen if fat is not absorbed properly or if certain medications are used such as antibiotics that kill the gastrointestinal bacteria that produce vitamin K. Some anticoagulants may also lead to vitamin K deficiency. Although vitamin K deficiency is rare, it is often overlooked. Vitamin K deficiency can lead to significant bleeding, poor bone development, osteoporosis, and increased cardiovascular disease.
Ultimately, vitamins are important and necessary for the body to function properly. If you are feeling abnormal, you may or may not be experiencing vitamin deficiency. Make sure to get your vitamins, but ensure that you are getting the amount you need. You can use the daily nutritional requirements by the FDA as a guide. Don’t consume too many vitamins as that can also cause some problems, such as toxicity. Over consumption tends to occur due to supplements, rather than diet, so before taking any supplements, it is best to talk to your doctor. Do your research, and make informed choices. I hope this helps!