Vitamin Types & Sources
Vitamins are essential micronutrients that the human body needs in small amounts to maintain normal metabolic functions, growth, and development. There are two types of vitamins: fat-soluble vitamins and water-soluble vitamins.
Fat-soluble Vitamins Functions & Sources
Fat-soluble vitamins are stored in the body’s fatty tissues and liver and can accumulate to toxic levels if taken in excess. The four fat-soluble vitamins are:
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Vitamin A: It is important for vision, immune system function, and cell growth. Sources include liver, dairy products, carrots, sweet potatoes, spinach, and kale.
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Vitamin D: It helps the body absorb calcium and is essential for bone health. It is produced by the body in response to sunlight and can also be found in fatty fish, egg yolks, and fortified dairy products.
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Vitamin E: It acts as an antioxidant and helps protect cells from damage. Sources include nuts, seeds, leafy greens, and vegetable oils.
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Vitamin K: It plays a role in blood clotting and bone metabolism. Sources include leafy greens, broccoli, Brussels sprouts, and liver.
Water-soluble vitamins Functions & Sources
Water-soluble vitamins are not stored in the body and are excreted in urine if taken in excess. The nine water-soluble vitamins are:
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Vitamin C: It is important for immune system function, wound healing, and collagen synthesis. Sources include citrus fruits, berries, kiwi, peppers, and broccoli.
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B vitamins: There are eight B vitamins, including thiamine (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), biotin (B7), folate (B9), and cobalamin (B12). B vitamins are important for energy metabolism, brain function, and cell growth. Sources include whole grains, meat, fish, eggs, dairy products, leafy greens, and legumes.
Conclusion
In conclusion, a balanced and varied diet that includes a wide range of nutrient-dense foods is the best way to ensure adequate intake of all the essential vitamins.
Daily Vitamin Intake
The daily vitamin intake, also known as the recommended daily allowance (RDA), is the amount of each vitamin that an average healthy person needs to consume daily in order to maintain proper bodily function. The RDA varies depending on age, gender, and other factors, such as pregnancy and breastfeeding.
The RDA for vitamins is established by the Food and Nutrition Board of the National Academies of Sciences, Engineering, and Medicine. It is based on the latest scientific research and takes into account the amount of each nutrient needed to prevent deficiency and maintain optimal health.
Recommended Daily Allowance (RDA)
Here are the RDAs for some of the most important vitamins:
- Vitamin A: 700 to 900 micrograms per day for men and women, respectively
- Vitamin C: 90 milligrams per day for men and 75 milligrams per day for women
- Vitamin D: 15 micrograms (600 IU) per day for adults up to age 70, and 20 micrograms (800 IU) per day for adults over age 70
- Vitamin E: 15 milligrams per day for men and women
- Vitamin K: 120 micrograms per day for men and 90 micrograms per day for women
- Thiamin (B1): 1.2 milligrams per day for men and 1.1 milligrams per day for women
- Riboflavin (B2): 1.3 milligrams per day for men and 1.1 milligrams per day for women
- Niacin (B3): 16 milligrams per day for men and 14 milligrams per day for women
- Vitamin B6: 1.7 milligrams per day for men and 1.5 milligrams per day for women
- Folate (B9): 400 micrograms per day for men and women
- Vitamin B12: 2.4 micrograms per day for men and women
It’s important to note that some people may need more or less of certain vitamins, depending on their individual health status and lifestyle factors. For example, pregnant women may need higher amounts of folate and iron, while older adults may need more vitamin D. It’s always a good idea to speak with a healthcare professional to determine your specific nutrient needs.