As we all know, the human body needs a range of vitamins to work properly. Vitamins are complex molecules which aid in the function of cells, tissues, and organs. Our bodies cannot produce vitamins, so we need to include them in our diets. Vitamins must be dissolved before they can be absorbed and used in the body.
Vitamins are categorized as either fat-soluble or water-soluble. Water-soluble vitamins are vitamins which dissolve in water. They are absorbed directly into the bloodstream, and any excess water-soluble vitamins are excreted in liquid waste. As a result, large amounts of water-soluble vitamins are usually not harmful.
In contrast, fat-soluble vitamins need fat to be dissolved. They are absorbed through the wall of the small intestine with the help of bile from the liver. Excess fat-soluble vitamins are stored in the liver and fatty tissues. They are stored over longer periods than water-soluble vitamins, so stores don’t have to be replenished as often. There is also a greater risk of toxicity if excess amounts are consumed.
The full list of fat-soluble vitamins includes just four vitamins: A, D, E, and K. Read on to find out why these vitamins are important, how to obtain them, and other important considerations.
Vitamin A is needed for proper functioning of several systems in the human body. It aids bone growth, tooth development, reproduction, cell division and gene expression. Vitamin A also regulates the immune system, keeps mucous membranes moist, and helps eye health. It is an important antioxidant which is needed for skin health and may even protect against certain cancers.
Beta-carotene is a vitamin A precursor which the body can convert to vitamin A. Many fruits and vegetables contain beta-carotene. The best beta-carotene sources are orange or dark green, such as carrots, squash, pumpkin, apricot, and dark green leafy vegetables.
Vitamin A deficiency is rare, but vitamin A toxicity is a more common problem. Toxicity can result from taking supplements containing large amounts of vitamin A in the retinol form. The beta-carotene form appears to be safe, so enjoy your carrots with no worries.
Vitamin D increases the amount of calcium absorbed through the small intestine, which helps in the formation of bones and teeth. Vitamin D also plays a role in immunity and controls cell growth. The most well-known source of vitamin D is dairy products, but it is also present in a variety of plant foods. Good vegan sources of vitamin D include dark green leafy vegetables like spinach and kale, white beans, soybeans, and certain fortified foods like orange juice and oatmeal. In addition to dietary sources, our skin also produces vitamin D when it is exposed to sunlight.
Generally, enough vitamin D can be obtained from a combination of food and vitamins, but certain populations are more at risk for vitamin D deficiency. Those who have dark skin, live in the northern hemisphere, or always use sunscreen may be unable to synthesize enough vitamin D from sunlight. Being elderly and having certain diseases can decrease the ability to synthesize or absorb vitamin D, potentially leading to deficiency.
If you have several of these risk factors, you might benefit from a vitamin D supplement. Most vitamin D supplements are derived from animals. Recently, though, the most potent form of vitamin D has been extracted from lichen. You can purchase a vegan, lichen-derived and third-party tested vitamin D supplement at an affordable price.
Vitamin E, also called tocopherol, acts as an antioxidant and protects vitamins A and C, fatty acids, and red blood cells from being damaged. Vitamin E, along with other antioxidants, can have preventative effects against heart disease, cancer, and other diseases. However, it seems antioxidants only have these positive effects when they are obtained from fruits and vegetables.
The foods with the most highly concentrated vitamin E are vegetable oils, but oils have downsides which are probably not worth the extra vitamin E. A healthier source of vitamin E is whole foods which naturally contain fat. Some of the best whole-food sources of vitamin E are sunflower seeds, almonds, wheat germ and avocado. Vitamin E deficiency is rare, and toxic doses of vitamin E usually cannot be obtained from food. Vitamin E supplements are not recommended since they haven’t been shown to provide any added benefits. In other words, as long as you eat a healthy diet you should not be concerned about vitamin E intake.
Vitamin K promotes normal blood clotting, bone strength, and cardiovascular health. It is needed to activate several proteins which are needed for blood, bone, and kidney functioning. Vitamin K also prevents the buildup of calcium in the blood vessels, making calcium more available for the body to use.
Vitamin K is produced by bacteria in the intestine and also is found in leafy green vegetables such as spinach, cauliflower, cabbage, and broccoli. Most people obtain enough vitamin K through diet, but deficiency can occur in infants and people taking blood thinners such as warfarin. Excessive amounts of vitamin K are not advised since they can break down red blood cells and cause liver damage. For more information about vitamin K, read my article on what vitamin K does for the body.
Great benefits in small, fat-soluble packages
Fat soluble vitamins are unique in how they are obtained, absorbed, and stored by the body. Each of these nutrients is needed only in small amounts, but each plays an essential role in the proper functioning of the human body. Vitamin D deficiency is the only common fat-soluble vitamin deficiency, and it can be corrected through supplementation. Excessive amounts of fat-soluble vitamins can result in toxicity, causing a variety of negative effects. Large amounts of vitamins are usually unintentionally consumed through multivitamins. If you choose to take a multivitamin, it’s important to make sure it doesn’t contain unnecessary, potentially harmful ingredients.
Obtaining the proper amount of fat-soluble vitamins should not be a concern for most people, but being aware of the requirements can help you to avoid potential problems. The best way to ensure you obtain all the fat-soluble vitamins you need is by eating a healthy, plant-based diet containing a variety of fruits and vegetables.