Vitamins are indispensable for life. Their deficiency or hypervitaminosis can cause even fatal pathologies. We will briefly illustrate what vitamins are used for and in which foods you can find them and how to assimilate them correctly. Synthetic Guide to Vitamins and Vitamin Classification:
The classification of vitamins
They are classified as: “protective foods”, together with mineral salts. They serve to regulate the exchange of substances, for example fats, sugars, proteins, etc., protect organs and mucous membranes, promote growth and keep away the risk of certain diseases.
Vitamins and mineral salts are not produced by our body: it is necessary to take them through nutrition. In fact, their deficiency can cause serious illnesses.
Vitamins are divided into:
- Fat-soluble: soluble in fat (they are: A – D – E – F – K)
- Water soluble: soluble in water (they are: P – C – group B)
It is important to know that when we eat foods with fat-soluble vitamins, for example A of which the carrot is rich, we must ingest fats: oils, etc., to be able to absorb them.
The same thing applies to water-soluble, we must ingest water in the same meal, otherwise the vitamins will be lost.
The fat-soluble vitamins, as well as the fats, are absorbed by the body into the large intestine , to then enter the bloodstream. They can accumulate in adipose tissue, along with fat and also in the liver, difficult, sometimes difficult, to have cases of hypovitaminosis. instead, excess fat and fat-soluble vitamins can cause damage to internal organs.
The water-soluble vitamins are also absorbed from the large intestine but, unlike the fat-soluble ones, they are conserved in our body for a short period, so it is difficult to find cases of hypervitaminosis. In fact, our body excretes the excesses of these vitamins in urine and sweat. The only exception is for the vit. B12, which is stored in the liver.
Stability and instability of vitamins:
The vitamins are unstable under certain environmental characteristics. After harvesting, some are thermolabile, that is they die with heat, others are sensitive to light, air, acidity or alkalinity (basic).
Let’s take the examples:
- Vitamin A: sensitive to heat, light, air and acidity.
- Vitamin B12: light sensitive.
- Vitamin C: sensitive to heat (dies immediately with a temperature of 40 ° and after two days at room temperature), in light, air and alkalinity (it is in fact contained in acidic foods such as spinach, peppers, rose canine, citrus fruits, etc.)
- Vitamin D: sensitive to air and acidity (it is enough to expose to the Sun a few body parts, for a few minutes every day, or accumulated in the summer, to fix the calcium in the bones).
- Vitamin E: sensitive to heat, light and air.
- Vitamin K: sensitive to light and alkalinity.
- Vitamin B1: sensitive to heat, air and alkalinity.
- Vitamin B2: sensitive to heat, light and alkalinity.
- Vitamin B3 or PP: resistant in all conditions.
- Vitamin B5: heat sensitive.
- Vitamin B6: light sensitive.
- Vitamin B9: sensitive to heat, light, air and acidity.
To obtain an excellent absorption of vitamins, the choice of foods, cooked or raw, will therefore be based on the instability of the environmental conditions.
For example, if you want to eat Vitamin C, you must ingest, therefore, the food that contains it (eg spinach), but must be freshly picked, raw and ingested with other acidic foods but not with carbohydrates (alkaline foods) , like pasta, rice or bread.
I also remember that vegetables should be ingested as soon as or just picked, due to the alteration of vitamins.
Today we know that the vegetables purchased are not always very fresh, so, if possible, choose your own (maybe organic) trusted greengrocer.
Also, it is necessary to know that all vegetables and fruits should not be refrigerated (placed in the refrigerator). The molecules alter and “cool”, a bit like us if we go out in the open air with a temperature of 4 °, without clothes.
Hypovitaminosis and hypervitaminosis: what causes:
- Vitamin A: its deficiency causes eye diseases, skin or mucosal lesions, with local infections. Its excess causes anorexia, asthenia, problems with bone growth.
- Vitamin B1: its deficiency causes Beri Beri, a disease that compromises muscle strength, the nervous system, the heart and the circulatory system.
- Vitamin B2: its deficiency can cause fissures on the sides of the mouth, seborrheic dermatitis, conjunctivitis.
- Vitamin B6: its deficiency causes dermatological forms, eczema and degenerative neuromuscular forms. In infants it causes convulsions, skin lesions, microcytic anemia.
- Vitamin B3 or PP: its deficiency causes Pellagra, a disease very present in the past, for those who used a diet low in protein and rich in corn flour (polenta). It causes fatigue, anorexia, headache, dermatitis, diarrhea, dementia.
- Vitamin B9: its deficiency causes hyperchromic or megaloblastic anemia (presence in the bone marrow of erythroblasts, or cells that must mature in red blood cells but cannot reach their maturation), leukopenia (few white blood cells), thrombocytopenia, skin alteration and mucous membranes.
- Vitamin B12: its deficiency can cause megaloblastic or hyperchromic anemia, due to the bad absorption of this vitamin in the intestine.
- Vitamin C: its deficiency causes Scurvy, a dietary deficiency disease, causing weakening of the matter inside the cells, causing widespread bleeding and delayed wound healing. In children it causes bone lesions. No vitaminous diseases were found. C, only a few cases of renal calculosis, indeed hypervitaminosis, seem to remove the risk of infectious diseases.
- Vitamin D: its deficiency can cause osteomalacia in adults, that is a defect in the calcification of bones, with pain and fractures to them. Its excess can instead cause decalcification of bone and calcemia, that is too much calcium that is deposited in the soft tissues such as the kidneys (lithiasis or calculosis) and in the vessel walls. In children, its deficiency causes rickets, does not calcify the long bones that remain soft and deform, with muscle weakness, intestinal atony, constipation.
- Vitamin E: its deficiency can cause muscle weakness with focal necrosis of the striated muscles, creatinuria (creatine, a muscle substance that conserves energy but is present in urine), haemolytic anemia (excessive destruction of red blood cells).
- Vitamin K: its deficiency in rare cases causes bleeding. In newborns after many antibiotic therapies, the near absence of bacterial flora can cause hemorrhage.
Main functions for each vitamin and in which foods can be found:
Vitamin A: Retinol Provitamin: Beta-carotene, other carotenes.
Sources: Fish liver oil, mammalian liver, milk, butter, cheese, eggs. Carotenes: broad-leafed vegetables, carrots, apricots, butter, aromatic herbs, radicchio, spinach, watercress, chives, chicory, beets, brussels sprouts, celery, orange vegetables. Functions: Constitutes rhodopsin (visual pigment). Promotes glycoprotein synthesis and maintenance of epithelia. It carries out a protective action against cancer.
Vitamin D: colicalciferol
Sources: Fish liver oil, mammalian liver, blue fish, milk, butter, eggs. Functions: It regulates the metabolism of calcium.
Vitamin E: tocopherol
Sources: Leafy vegetables, oil seeds and fruits, oils, liver, wheat germ oil, vegetable oils, dairy products, eggs. Sage, marjoram, rosemary, thyme, dried and ground basil.
Functions: Protects lipids from oxidation.
Vitamin K: Phylloquinone, prenylmenachinone, menadione.
Sources: intestinal flora, vegetables, spinach, crucifers (Cabbage family), asparagus, peas, beans, potatoes, tomatoes, green tea, minimum quotas in meat.
Functions: It has an antihemorrhagic action: implicated in the transformation of the active prothrombin.
Vitamin B1: Thiamine.
Sources: Brewer’s yeast, pericarp and germ cereals, legumes, fruit, liver, eggs, milk.
Functions: Coenzyme in the metabolism of carbon hydrates, transmission of the nervous impulse.
Vitamin B2: Riboflavin
Sources: Pericarp and germ of cereals, milk, eggs, liver, fish, whole grains, legumes, green leafy vegetables.
Functions: It is the FAD and FMN coenzymes implicated in biological oxidation.
Vitamin B3 (PP): Nicotinic acid, nicotinamide .
Sources: Brewer’s yeast, liver, kidney, lean meats, fish, legumes, oil seeds.
Functions: It is the NAD and NADP co-enzymes that accept hydrogen-donors in redox reactions.
Vitamin B5: Pantothenic acid.
Sources: Brewer’s yeast, liver, kidney, trout, gorgonzola, salmon, lobster, meat, eggs, cereal cuticle, peanuts, dried peas, soy, lentils, broccoli, cauliflower and cabbage.
Functions: Coenzyme A.
Vitamin B6: Pyridoxine
Sources: Yeast, cereal cuticle, liver, brain, meat, milk, cod, salmon, squid, lentils, leeks, fruit
Functions: It is the coenzyme of at least 60 enzymes involved mainly in the metabolism of amino acids.
Vitamin B8 (H): Biotin.
Sources: Beer Yeast, liver and offal, oilseeds, spinach, mushrooms, grapes, egg yolk, legumes, meat.
Functions: It is the coenzyme of decarboxylase and transcarboxylase.
Vitamin B9 (M): Folic acid.
Sources: Yeast, liver, asparagus, spinach, green leafy vegetables, fam. Cabbage, nettle, parsley, mint, legumes, soy, cereals.
Functions: In reduced form FH4 constitutes a coenzyme implicated in the transformation reactions of monocarboniose units.
Vitamin B12: Cyanocobalamine.
Sources: Foods of animal origin, salted and sweet aqua fish, eggs, milk, cheese.
Functions: Coenzyme in methylation reactions and intramolecular rearrangement of monocarboniose groups.
Vitamin C: Ascorbic acid.
Sources: Fresh fruits and vegetables, dog rose, red and black currant berries, medlar, kiwi, papaya, citrus fruits, chestnuts, blackberry, blackberry, raspberry, strawberry, juniper, hot pepper,, peppers, fam. Cavoli.
Functions: Involved as a redox system in many metabolisms. Detoxifying, antioxidant action. Strengthens the immune system.