Vitamins are a group of organic compounds your body requires for cell growth and development.
They play an essential role in ensuring that your body functions optimally. Vitamins are present in foods, fruits, and vegetables in not-so-large amounts. Everyone needs specific vitamins and other nutrients to live a healthy life. Unfortunately, lack of knowledge is one of the primary reasons you can miss out on these essential nutrients.
There are thirteen essential vitamins that your body needs to function. These vitamins belong to two main groups based on how they act in your body.
This article will share more details on these vitamins, including their functions, food sources, signs of deficiency, and the dangers of overconsumption.
Vitamin A is a fat-soluble vitamin that is naturally present in many foods. It exists in two primary forms:
Body requirements and absorption:
The recommended daily allowances (RDAs) of vitamin A vary by age and gender. Males 14 years old and older should take 900 micrograms (mcg). Women 14 years and older should take 700 micrograms (mcg).
Factors that aid the absorption of vitamins include:
Natural Sources:
Palm oil, carrots, beef liver, eggs, sweet potatoes, leafy vegetables like spinach and pumpkin leaves (ugu) are natural sources of vitamin A.
Signs of Vitamin A deficiency:
Dangers of overconsumption:
B complex vitamins are a group of essential nutrients comprising eight vitamins. These include vitamins B1, B2, B3, B5, B6, B9 and B12. They are all water-soluble vitamins. They work together to help you stay healthy.
Vitamin B1, known as thiamine, is a water-soluble vitamin. It dissolves in water and gets flushed out regularly. The body cannot store Vitamin B1, so you need it in your diet every day – luckily, you should be able to get all you need from there. This vitamin is essential during pregnancy and breastfeeding.
Functions
Body requirements and absorption:
Adults need 0.8 to 1.1 milligrams (mg) of thiamine daily. It is absorbed readily in the jejunum and ileum of your small intestine.
Natural sources:
Potatoes, brown rice, eggs, beans, lentils, and nuts are excellent sources of vitamin B1.
Signs of deficiency:
Fatigue and muscle weakness are common signs of thiamin deficiency. It can also lead to a neurological disease called beriberi. Beriberi causes muscle loss, numbness from nerve damage, and impaired reflex and motor function.
Dangers of overconsumption:
Overconsumption of thiamine is unlikely because your body will excrete the excess amounts through your urine.
Vitamin B2 is known as ‘the skin saviour’ because it maintains healthy skin, nails and hair. It is also known as riboflavin.
Functions
Body requirements and absorption
The recommended daily allowance (RDA) of riboflavin is about 1.3 mg of vitamin B2. Women usually need 1.4mg daily during pregnancy. It is absorbed in the epithelial cells of the small intestine.
Natural sources
Ugu (pumpkin leaves), milk, cheese, yoghurt, meat, and eggs are excellent sources of riboflavin.
Signs of deficiency
Dangers of Overconsumption
Vitamin B2 is generally safe, but your urine may appear yellow.
It is also known as niacin and exists in different forms. It exists in your food as:
Your body can also produce vitamin B3 from an amino acid called tryptophan. Consuming foods that are rich in protein will cause an increase in the tryptophan-nicotinamide conversion.
Functions
Body requirements and absorption
Adults need an average of 15 mg of niacin daily. Nicotinamide and nicotinic acid are absorbed in the small intestine.
Natural sources
Meat, fish, brown rice, peanuts and coffee are rich in vitamin B3.
Signs of deficiency
Vitamin B3 deficiency can cause pellagra. This condition is a combination of dermatitis, dementia, and diarrhoea characterized by:
Dangers of overconsumption:
Taking too much niacin can cause bloating, nausea, diarrhoea and liver damage.
Vitamin B5 is often called an ‘anti-stress vitamin.’ Your body requires this vitamin to make coenzyme A (CoA). CoA is responsible for several processes in your body, especially breaking down food to produce energy. Vitamin B5 is also known as pantothenic acid.
Functions
Body requirements and absorption:
Your body can’t produce pantothenic acid. You need a daily intake of 5mg from your diet if you are older than 14 years. The presence of gastric acid in your stomach aids vitamin B5 absorption.
Natural sources:
It can be found in avocados, chicken, mushrooms, and oats.
Signs of deficiency:
Dangers of overconsumption
Taking too much pantothenic acid is rare because your body will excrete the excess amounts through your urine.
Vitamin B6 exists in three major compounds, including
It can also exist in coenzyme forms, activating over 100 enzymatic reactions, including protein metabolism.
Functions
Body requirements and absorption
The recommended daily intake of vitamin B6 varies.
Males and females between 19 and 50 should take 1.3 milligrams (mg).
Men who are over 50 years old should take 1.7 milligrams (mg). Women over 50 years old should take 1.5 milligrams (mg).
Pregnant and breastfeeding women should take 1.9 milligrams (mg) and 2.0mg, respectively.
Vitamin B6 is absorbed in your small intestine. The type of food you eat may affect the absorption of vitamin B6.
Natural sources
Bananas, walnuts, oats, almonds, turkey, and whole wheat bread are excellent sources of vitamin B6.
Signs of deficiency
Dangers of overconsumption
High doses of vitamin B6 can cause brain and nerve problems.
Vitamin B7 is popularly known as biotin. It is an essential enzyme in your body that breaks down food substances.
Functions
Body requirements and absorption
It is recommended that adults consume 30 micrograms of biotin daily. If you are a breastfeeding mother, you should take 35 micrograms daily. Biotin is majorly absorbed in the small intestine.
Natural sources
Sweet potatoes, spinach, liver, sardines, red meat and eggs are packed with biotin.
Signs of deficiency
Biotin deficiency is rare. However, you will notice:
Dangers of overconsumption
There is no risk of overeating biotin from food.
Vitamin B9 exists in two primary forms:
These forms of vitamin B9 are often used interchangeably.
Functions
Body requirements and absorption
The recommended daily intake for teens and adults is 400 micrograms (mcg) daily. Breastfeeding mothers and pregnant women should take 400 and 600 mcg daily, respectively.
Vitamin C aids folic acid absorption in the small intestine and colon.
Natural sources
Oranges, lemons, beans, nuts, spinach, ugu (pumpkin leaf), and kidney beans are rich sources of folate.
Signs of deficiency
Dangers of overconsumption
Excess amounts of vitamin B9 are excreted through the urine. High amounts of vitamin B9 in supplements might interfere with certain medications.
Vitamin B12, or cobalamin, is the most structurally complex vitamin. Vitamins B6, B9, and B12 regulate homocysteine levels in your blood. Your body can store vitamin B12 in your liver for years.
Functions
Body requirements and absorption
Teens and adults above 14 should take 2.4 micrograms (mcg) daily. Vitamin B12 is absorbed in the small intestine.
Natural sources
Fish, meat, eggs, milk and fortified cereals are rich sources of vitamin B12.
Signs of deficiency
Dangers of Overconsumption
There is no risk of consuming too much cobalamin.
Also known as ascorbic acid, vitamin C is a water-soluble vitamin. Vitamin C is popularly known for its powerful antioxidant properties.
Functions
Body requirements and absorption
Daily requirements vary based on age. The recommended daily amount for vitamin C is 75 milligrams (mg) daily for women and 90 mg for men. During pregnancy, it is 120 mg a day.
Vitamin C absorption is easier when consumed alongside foods rich in iron.
Natural sources
Citrus fruits like oranges, guavas, berries, mangoes, and vegetables like bell peppers and tomatoes are excellent sources of vitamin C.
Signs of deficiency
Vitamin C deficiency leads to scurvy. If you have scurvy, you might experience fatigue, connective tissue weakness, and swollen and bleeding gums.
Dangers of overconsumption
Vitamin C overconsumption is rare, but it can cause stomach upset.
This is a fat-soluble vitamin that the body can also synthesize when exposed to sunlight. Another name for vitamin D is cholecalciferol.
Functions
It is necessary for:
Body requirements and absorption
The recommended daily amount for vitamin D is 15 micrograms (mcg) daily. The equivalent in the International Unit (IU) is 600 IU.
Adequate exposure to sunlight is also necessary to attain optimal levels of vitamin D. The presence of dietary fat in your gut enhances its absorption. However, the small intestine absorbs vitamin D dietary fat.
Natural sources
Sunlight is the primary source of vitamin D. You can also eat sardines, eggs, yoghurt, and liver, which are rich in vitamin D.
Signs of deficiency
Weak bones, bone, and muscle pain are common signs of vitamin D deficiency, which can lead to:
Dangers of overconsumption
Excessive intake can lead to hypercalcemia, causing symptoms like nausea, vomiting, and kidney damage.
Vitamin E is a fat-soluble antioxidant that exists in various forms. It is also called tocopherol. The most biologically active form of vitamin E is alpha-tocopherol.
Functions
Body requirements and absorption
The daily requirements vary based on age. The recommended daily amount of vitamin E is 15 milligrams (mg) for people above 14 years old. For women who are pregnant and breastfeeding, the daily recommended intake is 15 mg and 19 mg, respectively.
Vitamin E is absorbed in the small intestine.
Natural sources
Nuts, seeds, spinach, egg yolk, and vegetable oils are rich in vitamin E.
Signs of deficiency
Vitamin E deficiency is generally rare. However, it can cause haemolytic anaemia, a condition that destroys blood cells in newborns. Other signs of vitamin E deficiency include:
Dangers of overconsumption
Excessive vitamin E intake is uncommon, but high doses can prevent blood clotting. This can increase the risk of bleeding or haemorrhage.
Vitamin K is popularly known as the blood clotting vitamin. It is a group of fat-soluble vitamins. It exists in two main forms:
Phylloquinone is the main dietary form of vitamin K found in green leafy vegetables. Your body stores vitamin K in the liver, brain, heart, pancreas and bones. So, you may not need to eat large amounts of vitamin D.
Functions
Body requirements and absorption
The daily requirements for vitamin K vary based on age.
Children between 9 to 13 years should take 60 micrograms (mcg). People between 14 to 18 years old should take 75 micrograms (mcg). Women who are pregnant and breastfeeding should take 90 micrograms (mcg).
Vitamin K is absorbed through the ileum and jejunum of the small intestine.
Natural sources
Ugu (pumpkin leaves), fermented soybeans, locust beans, e.g., ogiri and iru, cabbage and cow liver are rich sources of vitamin K.
Signs of deficiency
Difficulty with blood clotting, which would affect how your wounds heal.
Dangers of overconsumption
Overconsumption of supplements is rare, but excessive intake can interfere with blood-thinning medications like Warfarin, leading to blood clotting disorders.
Vitamins play diverse and vital roles in maintaining your health and overall well-being. It would be best if you had to understand each vitamin’s functions, sources, and recommended daily intake. It would help if you also remembered that balance is critical. This will ensure that your body functions optimally. Curate a diet filled with various foods, fruits, and vegetables rich in nutrients and flavour for a healthier, happier life.
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