Vitamins are organic compounds that are required as nutrients by the human body. These nutrients can perform a variety of functions for overall health and well-being. While there are numerous nutrients that all have a variety of functions in the body, vitamins are the ones that humans are incapable of producing on their own, and must therefore be obtained via the diet. Vitamins are essential nutrients for the maintenance of the body, alongside dietary minerals, essential fatty acids, and amino acids. Vitamins are classified based on whether they dissolve in water or in fat. Of the 13 vitamins that are required by the human body, four are fat-soluble, while the remaining nine are water-soluble. Water-soluble vitamins are readily excreted from the body and are dissolved easily in water.
These vitamins are not readily stored by the body, making daily intake ideal in a nutritional sense. Fat-soluble vitamins are absorbed via the intestinal tract, and have a higher chance of accumulating in the body. As such, the average person is less likely to need supplements for them if their regular diet provides sufficient quantities of the vitamin already.
Since the body doesn’t produce vitamins on its own, the daily requirements on a nutritional level were fulfilled through one’s diet. Fruits and vegetables, most notably, are among the major sources of vitamins. A balanced diet can provide the average person all of the vitamins it needs on a daily level, but not everyone has a balanced diet. Up until the 1900s, this was a major nutritional concern, as there was no way to combat deficiencies because the locally available foods didn’t have all the vitamins required. Since the discovery of vitamin A in 1909, however, medical science has found ways to synthesize vitamins into a supplemental form, allowing people with local diets lacking in certain nutrients to balance things out.
The various vitamins each perform some manner of function in the body. Vitamin A, for example, is needed by the eye, and is known to play a role in maintaining the light-absorbing capabilities of the retina. This vitamin is also known to contribute to the ability to see in color. A lack of vitamin A can cause someone to develop night-blindness, making it impossible for them to see in low light conditions. Skin health benefits have also been tied to vitamin A. The mechanisms involved in how vitamin A helps maintain the health of the skin remains unknown, but are being researched. 13-cis retinoic acid, a form of vitamin A, is among the most effective treatments for acne.
The B-complex vitamins are so named because it consists of multiple nutrients, each one having a different function in the body. The B-complex vitamins are all water-soluble, and are thus not readily stored in the body. Of the vitamins that form the B-complex group, vitamins B6 and B12 are among the most popular. Vitamin B6 is known for its role in the process of gluconeogenesis, which is how the body converts the molecules of food into simpler carbohydrates that it uses for energy. Vitamin B12, on the other hand, has a key role in keeping the brain and nervous system functioning normally, and also plays a role in the formation of blood cells.
Vitamin C, perhaps the most commonly known of the vitamins, is required in a wide range of metabolic reactions. Unlike most vitamins, it is made internally in humans, but not in large amounts. Initially, vitamin C was found to have a role in the prevention of the disease scurvy and other diseases in humans, with fruits containing large amounts of vitamin C being among the earliest preventative measures adopted by the medical field. Vitamin C has been found to behave as an antioxidant, helping combat the cardiovascular problems caused by oxidization. Vitamin C is also believed to boost resistance to infection.
Vitamin D, which comes in two major forms, is usually obtained via exposure to sunlight, but can also be acquired from food sources and supplements. Low levels of vitamin D have sometimes been pinpointed as one of the possible causes of a form of depression known as seasonal affective disorder, a condition that manifests during the cold winter months, when there is less sunlight. Aside from this, vitamin D plays a role in the maintenance of various organ systems in the body after it has been activated, since it usually remains dormant. Insufficient levels of vitamin D have also been pinpointed as being one of the possible causes of bones becoming thin, or brittle.
Since the human body doesn’t readily store a majority of vitamins, regular consumption is needed to keep them at the right levels. For a balanced diet, the problem of a vitamin deficiency would be rare, as the person would theoretically have sufficient levels of the essential vitamins to function normally. Dietary supplements are often used to make up for any lack in the diet, and usually contain amounts of vitamins that are far higher than would normally be ingested through food.