Vitamins are organic molecules that the body needs in small amounts for normal function. Most people can meet their nutrient requirements through a healthy eating pattern that includes nutrient-dense foods.
Most vitamins are fat-soluble, including A, D, E, and K, while others, like C, are water-soluble. Some, such as beta carotene and folic acid, may be toxic in large doses.
Vitamin A is a fat-soluble vitamin that occurs naturally in animal products, including liver, whole milk dairy, and fish oil. It is also made in the body from provitamin A carotenoids, such as beta-carotene. Vitamin A supports eye health and immune function and promotes cell growth and reproduction. It may also reduce the risk of certain cancers and help fight infections. Vitamin A toxicity (hypervitaminosis A) is rare when consumed in the recommended amounts, which are measured using retinol activity equivalents (RAE) and % Daily Value on food labels.
Most people should get all of their vitamins and minerals from eating a variety of foods. However, dietary supplements and fortified foods can be helpful in meeting nutrient needs when dietary patterns are not ideal. See the Dietary Guidelines for Americans and Talk to Your Doctor. This information is provided for general educational purposes only.
Vitamin C (also known as ascorbic acid) is a water-soluble nutrient required for normal human growth and development. It is found naturally in many fruits and vegetables, and also as a dietary supplement. It is necessary for the formation of collagen and the enzymatic production of some neurotransmitters. It is also an antioxidant and may protect against certain cancers and promotes iron absorption, especially in those receiving chemotherapy. Unlike most other animals, humans cannot synthesize vitamin C endogenously and must therefore acquire it through the diet.
It has been shown to reduce cold symptoms, including duration and severity, but does not shorten the duration of the flu. It also prevents scurvy and may aid in the recovery of some gastrointestinal infections, such as gastroenteritis and peptic ulcers. It has relatively low toxicity and can be taken at high doses without adverse effects.
Vitamin D, nicknamed the “sunshine vitamin” for its ability to be made when the skin is exposed to sunlight, is important for promoting bone health. The nutrient helps with calcium absorption, and without it, bones can become thin and brittle. Vitamin D also plays a role in cell growth and the modulation of immune function.
Whether obtained through sun exposure, foods, or supplements, vitamin D must undergo two hydroxylations in the body before it becomes physiologically active as 1,25-dihydroxy vitamin D (25(OH)2D), or calcitriol. The serum concentration of 25(OH)D is currently the main marker for vitamin D status.
Studies link Vitamin D to several health outcomes, including bone health and osteoporosis, cancer, cardiovascular disease, depression, multiple sclerosis, type 2 diabetes, weight loss, and immune function. However, a report by the Institute of Medicine found that evidence was inadequate to establish a clear relationship between Vitamin D and many other health outcomes.
Vitamin E is a powerful antioxidant that protects cells against damage from free radicals and supports immune function. It also helps slow down age-related eye conditions like cataracts and macular degeneration.
The nutrient carries anti-inflammatory properties and preserves the integrity of skin lipid components, according to a study published in PLoS One (opens in new tab). It may even help prevent UV-induced photoaging, such as wrinkles, uneven skin texture, and hyperpigmentation.
Clinical trials suggest that regular vitamin E supplementation is a critical initial step in atherosclerosis, which may help prevent CHD by inhibiting the oxidation of low-density lipoprotein cholesterol. However, most studies have been conducted on middle-aged and older adults with heart disease or risk factors for it. Studies in healthy people with no known heart disease have shown mixed results. If you are looking for a medicine to deal with male ED problems, you can Vidalista 20mg and Buy Vidalista 40. Vitamin E is found in a variety of foods including dark green vegetables, nuts, seeds, and whole grains.
Vitamin K is a fat-soluble vitamin necessary for the post-synthesis modification of proteins involved in blood clotting (K from the German word Coagulation) and in controlling the binding of calcium to bones and other tissues. It is found in foods and dietary supplements in the forms of phylloquinone (phytyl) and menaquinone (many). Foods rich in this vitamin include green leafy vegetables, such as collards, spinach, and kale; soybean and canola oils; and meats.
Observational studies have suggested a relationship between dietary intake of phylloquinone and hip fracture in older adults. However, data are limited. Vitamin K is not considered to be a deficiency nutrient and it is unlikely that people will reach high intakes of this nutrient because phylloquinone in foods is tightly bound to chloroplasts and is only minimally absorbed.
Folic acid is a vitamin that helps the body create new cells. It is also important for healthy blood and is found in foods like fruits, vegetables, whole grains, and meat. Folic acid is especially important for women who may become pregnant because it can help prevent serious birth defects such as spina bifida.
People who are not pregnant should get enough folate from the food they eat and dietary supplements. Look for the %DV for folate (or mcg DFE) on the Nutrition Facts or Supplement Facts label.
Folic acid can change the way your body absorbs and uses phenytoin, an antiepileptic medication. Talk to your doctor before taking folic acid if you take phenytoin.
Vitamin B6, or pyridoxine, is one of the eight B vitamins that are water-soluble and essential for human health. It helps convert carbohydrates into fuel for the body and is needed for protein metabolism. It also plays a role in the formation of neurotransmitters, the chemicals that allow brain and nerve cells to communicate with each other. Vitamin B6 is also needed for normal cellular function and to support a healthy immune system.
Good food sources of vitamin B6 include poultry, fish, avocados, potatoes, chickpeas, and bananas as well as fortified breakfast cereals. It is also available as a dietary supplement.
Vitamin B12 is found naturally in foods of animal origin and is available as a dietary supplement. Foods that contain vitamin B12 are beef, fish (such as trout and haddock), shellfish, eggs, and milk (including soy and some non-dairy alternatives).
The nutrient is bound to protein in the food and must be released before absorption. In the stomach, hydrochloric acid and gastric protease degrade the binding proteins, releasing the vitamin B12 into the duodenum where it binds with intrinsic factor, a transport and delivery binding protein secreted by parietal cells of the stomach.
Once absorbed, vitamin B12 is converted to the metabolically active forms methylcobalamin and 5-deoxy adenosylcobalamin. These cobalamins participate in the metabolism of proteins, fats, and carbohydrates. They also play a role in the maintenance of blood cells and in the production of red blood cells.
Biotin, also known as vitamin B7, is a water-soluble vitamin that functions as a coenzyme in several metabolic pathways involved in the metabolism of fatty acids and carbohydrates, including gluconeogenesis (synthesis of glucose from noncarbohydrates). It has been used as a supplement to treat brittle nails and thinning hair and as an ingredient in some skin and nail care products.
Biotin is found in many foods, including liver, cauliflower, eggs, salmon, whole grains, nuts and seeds, and soy flour. It is often added to multivitamins and hair/nail/skin supplements. Large doses of supplemental biotin may interfere with some lab tests, so people taking biotin should follow recommended dosages and consult a health professional. Recommended dietary allowances for Biotin vary by age and gender.
Pantothenic acid, also known as Vitamin B5, is part of the B complex group of vitamins. Like other B vitamins, it helps the body turn food into fuel and use fats and protein. It is water-soluble and cannot be stored in the body, so it must be consumed daily.
It has been suggested that pantothenic acid may help reduce cholesterol levels, but more research is needed in this area. It has also been used to treat rheumatoid arthritis. Several studies have found that calcium pantothenate improves symptoms of the condition, such as morning stiffness and pain.
Pantothenic acid is incorporated into coenzyme A, which plays a key role in many metabolic processes. It is also a component of the membranes of the cells of all organisms. It is also a key player in the formation of collagen and elastin.