Vitamins are molecules necessary for the body in the same way as fats, carbohydrates and proteins. They are not produced by the body, but mainly provided by food. They guarantee the proper functioning of our cells.
What are their roles and how do they work? Where can I find vitamins?
What are the different vitamins and what are their roles?
Vitamins are essential for various mechanisms of action, and daily intakes are necessary to avoid deficiencies. A healthy diet is all it takes to get enough vitamins.
In total, there are 13 vitamins classified in 2 categories: water-soluble vitamins and fat-soluble vitamins. The water-soluble vitamins include vitamins C and B (B1, B2, B3 or PP, B5, B6, B8, B9 and B12); while the fat-soluble vitamins are vitamins A, D, E and K.
- The role of vitamins is essential in all biochemical processes. They participate in enzymatic reactions and help regulate metabolism. They also release energy and participate in the synthesis of bones and tissues.
- Vitamin A is involved in vision and the preservation of the immune system, the development of bone and skin growth.
- Vitamin B supports energy production, B9 and B12 are responsible for red blood cell production, protein synthesis, cell health and play a role in the central nervous system.
- Vitamin C has an antioxidant effect and acts as a barrier to infection, protecting the blood vessel walls.
- Vitamin D can be ingested, but can also be synthesised through sun exposure – it is partly responsible for the regulation of calcium metabolism.
- Vitamin E includes tocopherols and tocotrienols. It has an antioxidant and anti-inflammatory action. There are 8 vitamins E.
- Vitamin K plays a role in coagulation and cell growth, strengthens bones and has anti-inflammatory properties. It is divided into two large families: the phylloquinones and the menaquinones
HOW DO VITAMINS WORK IN THE BODY?
Vitamins are water-soluble or fat-soluble. Two different processes take place after ingestion.
Water-soluble vitamins C and B dissolve in water. They spread in body fluids without being stored, which makes them non-toxic. They are excreted in the urine even if too much of it has been absorbed. On the other hand: a diet must provide 50% of the recommended daily intake or else there will be a deficiency. They are very active between 8 and 14 hours after their absorption. They are mainly found in food.
Fat-soluble vitamins are stored in fatty tissue after being dissolved.
WHICH FOODS ARE RICHEST IN VITAMINS?
Water-soluble vitamins are contained in fruit and vegetables and fat-soluble vitamins in food lipids – i.e. fatty fish, oils, offal and liver, egg yolks.
- Vitamin A is mainly found in the form of retinol in foods of animal origin: cod liver oil, butter, eggs, milk or cheese.
- Provitamin A and beta-carotene are found in carrots, spinach, and leeks.
Vitamin B is found in meat, fish and beans. - Vitamin C, or ascorbic acid, is found in fruits and vegetables: citrus fruits, kiwis, peppers and strawberries.
- Vitamin D is found in fatty fish: salmon, mackerel, herring, sardines and cod liver.
- Vitamin E is found in olive and rapeseed oils, almonds, hazelnuts, peanuts, spinach and avocado.
- Vitamin K is found in green leafy vegetables such as spinach, parsley, salads, but also in offal, meat and cheese.