How vitamins work
By Marshall Brain
http://www.JewishWorldReview.com | (MCT) Every day of your life, chances are, you think about vitamins. You read about vitamin content on the nutritional label of every food you eat. Breakfast cereals and many drinks talk about vitamins right on the label. There are all the TV and radio spots advertising vitamins. You may even take a vitamin pill when you wake up.
It all begs the question: what, exactly, is a vitamin? Vitamin C, for example: What is it? And why do you need to "take" vitamin C every day?
Here is the basic definition of a vitamin: A vitamin is a small molecule that your body must have in order to carry out a certain chemical reaction. In some cases your body has no way to create vitamin molecules itself, so the vitamin molecules must come in through the food that you eat. In other cases your body has a way to make a vitamin molecule, but may not make enough. The human body is known to need at least 13 different vitamin molecules.
For example, your body needs vitamin C, also known as ascorbic acid. It is a very simple molecule containing 6 carbon atoms, 8 hydrogen atoms and 6 oxygen atoms. Your body needs this molecule for several reasons, but most importantly because of collagen. When your body produces collagen, it performs a chain of chemical reactions, and the vitamin C molecule is an essential part of the chain. Since collagen is used in everything from skin to blood vessels, you can see how important vitamin C can be. Without it your blood vessels weaken, your teeth start to fall out, etc., and you eventually fall apart and die from a lack of collagen. All because of one missing molecule.
Vitamin D is another simple molecule that is incredibly important. We actually have the ability to produce vitamin D in our skin, but to do it we have to have regular exposure to the sun's ultraviolet rays. Without enough sun exposure, people get different ailments depending on their age. In children, a lack of the vitamin D molecule causes rickets, which softens the bones and causes them to deform or break easily.
Why do we need to "take" these molecules? You can see that the human body is equipped to create its own vitamin D, but our lifestyles have changed. People "in the wild" lived outdoors and they got sun exposure every day. Modern humans can often spend days at a time indoors, especially in the winter, with very little sun exposure. So, to prevent rickets, we add vitamin D to milk and other foods just in case a child isn't getting enough naturally.
The case of vitamin C is even more interesting. You have probably noticed that dogs have absolutely no need for citrus fruits. On the other hand, human beings tend to enjoy them. In fact, if you were to become vitamin C deficient, you would think that something like an orange tastes fabulous, to the point where you might even eat the skin. The reason why dogs don't have any interest in citrus fruits is because they, like most animals, produce their own vitamin C molecules inside their own bodies. Human beings, like many other ape species, lost this ability because of genetic damage that occurred somewhere in the evolutionary chain. Apparently, at some point during the evolutionary process, the vitamin C gene was damaged. But our ancestors got enough vitamin C in their diets so that it did not matter. We inherited this damaged gene, so humans must get vitamin C from food as well.
Although we know the basics, we still have a lot to learn about vitamins. For example, we know for sure that if you don't get any vitamin C, you will die. But many people believe that if you take massive amounts of vitamin C, there is a health benefit. Is this true? Recent research suggests that it probably is not true. Vitamin K wasn't really understood until the 1970s, and we are still learning about it. There may be a few other vitamins lurking out there waiting to be discovered.
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