As soon as you were old enough to understand words, your parents started telling you to eat your vegetables so you would get enough vitamins. hangover iv long island as a child you took a daily vitamin – perhaps you still take vitamin supplements. It is common knowledge that vitamins are necessary to maintain a healthy body. But what are vitamins, why do we need them, and where, specifically, do they come from?
What is a Vitamin?
Vitamins are substances that are not produced directly within the body but yet are necessary for its proper function. Different organisms require different vitamins, and the function of specific vitamins may vary from organism to organism. Humans require 13 different vitamins, all of which can be gotten from the foods that we eat. We require very small amounts of vitamins for the body to function correctly.
There are 2 different types of vitamins – those that are fat-soluble and those that are water-soluble. Water-soluble vitamins, such as vitamins B (most of the 8 types of B vitamins) and C, are easily dissolved in water and pass through the human body quickly, with anything not used immediately by the body excreted via urine. Fat-soluble vitamins are stored by the body for up to several months and used when needed. Vitamins A, D, E and K are all fat-soluble vitamins.
Throughout history, before the discovery of vitamins, different societies have been aware of the connection between our health and the foods that we eat. A great and often-cited example is the problem of scurvy aboard sailing vessels during the 1700’s and before. We now know that scurvy is caused by a deficiency in vitamin C, however at the time there were several different theories as to its cause. Some societies thought the disease was due to a lack of proper exercise when aboard a ship for months at a time. Others thought it more the effect of contaminated food. A Scottish surgeon, James Lind, identified in 1753 that it was the lack of fresh fruits and vegetables aboard ship that was causing the disease. The British Royal Navy listened to Doctor Lind, and started carrying limes and lemons aboard their ships. Scurvy was eliminated as a problem for the Royal Navy, and English sailors acquired the nickname ‘limey’.
Why Do Humans Need Vitamins?
Each vitamin has specific functions within the body. Some work as hormones (Vitamin D) and others function as antioxidants (Vitamin E). Others, such as the B vitamins, function as catalysts for metabolism. If a body does not get the required amount of vitamins, the areas where the vitamins work will be harmed, and the person may also develop a deficiency disease, such as scurvy in the case of a Vitamin C deficiency. Each vitamin has a very specific deficiency disease. What is the function of each vitamin needed by humans?
- Vitamin A – Essential for good night vision and color vision, and regulates tissue and cell growth.
- Vitamin B (8 types) – Needed for the production of red blood cells, which transport oxygen throughout the body. Essential for the maintenance of good metabolism.
- Vitamin C – Aids in healing and muscle health, and also fortifies the immune system.
- Vitamin D – Needed for strong bones and teeth, and also helps in the absorption of calcium.
- Vitamin E – Good for healthy tissues in eyes, skin and liver.
- Vitamin K – Necessary for the blood to clot properly.
Where do we get Vitamins?
Prior to the last several decades, food was the only source of vitamins. More recently, in developed nations, vitamin supplements have become available. Some people require supplements if their diet is lacking in a particular vitamin or they have a disorder that prevents their body from processing vitamins properly. The majority of people in developed nations have no need for supplements, because vitamins are readily available in common foods. Some foods are even fortified with specific vitamins, as is the case with milk fortified with Vitamin D. In poor countries around the world where a variety of healthy food is not easily available, deficiency diseases are quite common. A good example is rickets, caused by a Vitamin D deficiency.