Pure vitamin A (retinol) is a lipid-soluble vitamin. It is primarily found in animal sources that contain fat. Vegetable sources contain a lipid-soluble precursor of vitamin A called beta-carotene. Pure vitamin A is primarily stored in the liver and in fatty tissue, for which reason we do not need a daily supply of the nutrient. Vitamin A and zinc work together. A deficiency in one nutrient will therefore affect the other. On a global scale, vitamin A deficiencies are widespread. In Western countries vitamin A deficiency is normally seen in connection with chronic disease. Vitamin A is destroyed when exposed to oxygen or heat, for instance during cooking.

B vitamins are water-soluble and because they do not get stored in the body, we humans depend on regular intake of them. B vitamins work in synergy in a highly complicated teamwork setup. They take part in most of the body's enzymatic processes, some more actively than others. The uptake of B vitamins depends on gastric acid and digestion.

B vitamins:

Vitamin B1 (thiamine)
Vitamin B2 (riboflavin)
Vitamin B3 (niacin)
VitaminB5 (pantothenic acid)
Vitamin B6 (pyridoxine)
Biotin (vitamin B7, vitamin B8, vitamin H)
Folic acid (folate, folacin, vitamin B9)
Vitamin B12 (several types of cobalamin)

Vitamin B1 is water-soluble and because it does not get stored in the body we depend on regular intake of the nutrient. In the 1920s, the Japanese scientist Umetaro Suzuki discovered vitamin B1 in rice shells and observed that this nutrient counteracted the classic deficiency symptom beriberi. Vitamin B1 is destroyed by alkaline substances and heating but not by freezing

Functions and importance for

• Energy metabolism and carbohydrate metabolism
• Normal energy levels
• Normal nervous and brain function
• Maintenance of psychological balance
• Normal muscle and heart function
• Production of hydrochloric acid in the stomach and normal digestion
• Antioxidant that protects against free radicals

Vitamin B2 is water-soluble and because it does not get stored in the body we depend on regular intake of the nutrient. Vitamin B2 is also known as lactoflavin and is used as a yellow colouring agent/additive in various foods. When ingested in very large quantities vitamin B2 causes the urine to turn highly yellow. Vitamin B2 is destroyed by light, heating, and alcohol.

Vitamin B3 is water-soluble and because it does not get stored in the body we depend on regular intake of the nutrient. Niacin is a common term for nicotinic acid and nicotinamide. The body's metabolism is able to synthesise part of its required niacin from vitamin B6 and tryptophan, an amino acid which is primarily found in meat. Vitamin B3 is destroyed by heating.

Functions and importance for

• Energy metabolism (turnover of carbohydrate, fat, and protein)
• Energy levels
• Vasodilation
• Circulation and cholesterol balance
• Nervous system
• Mental balance
• Skin and mucous membranes
• Reduction of fatigue and exhaustion

Pantothenic acid originates from the Greek word pantos, which means everywhere. As the word suggests, this vitamins is found in both plants and animals. Vitamin B5 is water-soluble and because it does not get stored in the body we depend on regular intake of the nutrient. Vitamin B5 is destroyed by heating and freezing.

Functions and importance for

• Energy turnover
• Building block of enzymes that are used to burn carbohydrate, fat, and protein
• Nervous system. Involved in the synthesis of signaling substances (neurotransmitters)
• Mental balance
• Digestion. Involved in the production of bile acid
• Involved in the synthesis of cholesterol and vitamin D
• Involved in the synthesis and metabolism of steroid hormones such as sex hormones and corticosteroids
• Reduction of fatigue and exhaustion

Vitamin B6, also known as pyridoxine, is converted to the active forms, pyridoxal phosphate and pyridoxamine phosphate. Vitamin B6 is water-soluble and because it does not get stored in the body we depend on regular intake of the nutrient. Vitamin B6 is destroyed by heating and light.

Functions and importance for

• Energy turnover, especially the metabolism of protein and glycogen (sugar stored in the liver and muscles)
• Energy levels
• Blood levels of the amino acid homocysteine
• Nervous system
• Mental balance
• Formation of red blood cells that carry oxygen to all parts of the body
• Immune system
• Regulation of hormonal activity
• Reduction of fatigue and exhaustion
• Antioxidant that neutralises free radicals

There are various forms of biotin and they all belong to the family of B vitamins. Biotin is synthesised from bacteria (including gut bacteria) and mold and yeast fungus, algae, and certain plants. Biotin is water-soluble and because it does not get stored in the body we depend on regular intake/production of the nutrient. Biotin is removed when boiled in water.