Vitamins are organic coenzymes (“cofactors”) and can be split into two categories: Fat-soluble and Water-soluble. Fat soluble vitamins are fat soluble because they are fats. Water soluble are not soluble in fats and are more like amino acids.
Fat Soluble Vitamins
Let’s start with Vitamin D (aka calciferol and cholecalciferol) since we already talked about how it’s a steroid hormone when we reviewed lipids.
Vitamin D (calciferol) is a steroid hormone made by cholesterol on your skin. We don’t make enough of this hormone so we make sure we do by making sure it’s in foods and/or taking a supplement. If we don’t get enough vitamin D, especially children, we get something called rickets where the bones are weak and things like scoliosis or bowed legs will form. Rickets does not exist in this country because they add this steroid hormone into the milk and call it Vitamin D.
Vitamin A (retinol) acts as a coenzyme for the photoreceptors in our eyes that is needed for a chemical reaction that allows us to see. It is especially important for darkness and not enough of it leads to night blindness. Why it’s chemically called retinol is because the back of the eye is the retina. It’s also needed by skin.
Vitamon E (tocopherol) is needed to produce RBC’s in our bone marrow. If someone doesn’t produce enough RBC’s, then we say they are anemic. The reasons for that may not be because they don’t have enough Vitamin E, though, there are dozens of other reasons that may cause anemia. Vitamin E is also an antioxidant which we will discuss later in detail about that.
Vitamin K (phylloquinone) is needed for normal blood clotting. Blood clotting is a series of chemical reactions where vitamin K is needed. If someone doesn’t have enough vitamin K, they would tend to keep bleeding. If you’ve heard of coumadin/warfarin/dicoumarol, it’s a blood thinner. It prevents blood clotting so clogged up arteries don’t occur and people won’t have heart attacks. This medicine works by interfering with Vitamin K so that the blood won’t clot. It’s a Vitamin K antagonist or blocker. If someone takes too much coumadin, the treatment for it is actually Vitamin K.
It’s possible to overdose and take too much of these fat soluble vitamins. This is one of the lessons that Americans don’t understand. The body works optimally when we have the right amount, nothing less or more than normal. When we talked about lipids and steroid hormones specifically, we mentioned that we need salt, sugar and cholesterol but too much of it leads to high blood pressure, diabetes and heart attacks, respectively. The same goes for fat soluble vitamins, we need them to live but too much of it is bad because they accumulate in the fatty tissues of the body.
Water Soluble Vitamins
Since these are all water soluble, they don’t accumulate in our tissues, the body does not store them and they come out of our urine very quickly . If you took massive amounts of Vitamin C, you can’t overdose on it. It causes your urine to turn very yellow and after you pee a couple times, all the vitamin C will be gone.
Vitamin C (ascorbic acid) acts as a coenzyme for collagen synthesis. Collagen is a protein that is created and secreted by fibroblasts. Collagen is found in skin, bones, tendons and gums. Many connective tissues contain collagen. An example of a tissue that contains fibroblasts that manufactures collagen is known as loose areolar connective tissue. This is the most pervasive type of CT. Another type that has collagen is dense fibrous connective tissue (regular and irregular). In order for these tissues to produce these things, they need Vitamin C. If the tissue doesn’t have enough collagen, this condition is known as scurvy where the skin, gums, tendons, even the bones (anywhere that has collagen), become thin and weak and bleeds easily. Also, it’s an antioxidant.
B-complex Vitamins: All the B vitamins play a role in metabolism. We are going to focus on niacin, riboflavin and pantothenic acid.
Niacin is part of a larger coenzyme called NAD which is important for the transfer of electrons.
Riboflavin (B2) is part of a larger coenzyme called FAD.
Pantothenic acid (B5) is part of another larger coenzyme called CoA (Coenzyme A)
Now it’s time to review the final post in our biological chemistry makeup… MINERALS!
Now let’s learn about our next compound that is inorganic .. Minerals!
- Intro to Physio and Organic Molecules
- Nucleic Acids