Selenium exists in two forms: inorganic (selenate and selenite) and organic (selenomethionine and selenocysteine). Both forms can be good dietary sources of selenium.

Most selenium that is present in human tissues is in the form of selenomethionine where it can be incorporated non-specifically with the amino acid methionine in body proteins. Skeletal muscle is the major site of selenium storage, accounting for approximately 28% to 46% of the total selenium pool.

Effects

Because of seleniums’ effects on DNA repair, apoptosis, and the endocrine and immune systems as well as other mechanisms, including its antioxidant properties, selenium might play a role in the prevention of cancer. Selenium also supports the immune system by scavenging oxidative products that are produced during an immune response when invading viruses are attacked.

In addition, selenoproteins help prevent the oxidative modification of lipids, reducing inflammation and preventing platelets from aggregating. As a consequence, selenium could reduce the risk for cardiovascular diseases. Some studies have suggested that selenium may prevent the cognitive decline in elderly.

The European Food Safety Authority (EFSA) has acknowledged the following beneficial effects as a basis for health claims:
• Selenium contributes to normal thyroid function
• Selenium contributes to normal function of the immune system
• Selenium contributes to the protection of DNA, proteins and lipids from oxidative damage
• Selenium contributes to the maintenance of normal nails
• Selenium contributes to the maintenance of normal hair
• Selenium contributes to normal spermatogenesis

• Thiamine – B1
• Riboflavin – B2
• Niacin – B3
• Pantothenic acid – B5
• Pyridoxine – B6
• Biotin – B7
• Folate – B9
• Cobalamin – B12

Since most B-vitamins are combined in the same food sources (grains, meat and fish), they easily interact and support each other’s function. These vitamins mainly function as co-enzymes in a variety of metabolic and biochemical reactions. B vitamins are essential for:
• Maintaining the energy metabolism
• Cardiac function
• Proper growth and development
• Maintenance of cells and organs

Biotin – B7

Biotin has an important role in the enzymatic breakdown of macronutrients (fats, carbohydrates, and proteins) which is important for the energy metabolism. This vitamin B7 improves the synthesis of keratin and therefore it is important for the normal growth of hair and the health of the skin and nails.

EFSA has acknowledged the following beneficial effects as a basis for health claims:
• Biotin – B7 contributes to macronutrient metabolism
• Biotin – B7 contributes to normal energy-yielding metabolism
• Biotin – B7 contributes to normal psychological functions
• Biotin – B7 contributes to maintenance of normal skin and mucous membranes
• Biotin – B7 contributes to normal function of the nervous system

Vitamin C plays a key role in several bodily functions including:

Antioxidant – Protection

Vitamin C is well known for its antioxidant properties; it cooperates well with vitamin E and prevents alone and in combination with vitamin E against oxidative damage from free radicals. By limiting oxidative damage, vitamin C helps to reduce the risk for chronic diseases including hearth diseases. Some research has suggested that vitamin C may help treat cancer by fighting oxidative damage.

Normal structure of tissues

Sufficient daily intake of vitamin C improves repair of tissues such as bones, teeth, skin and blood vessels. This is because vitamin C contributes to the production of collagen which is primary for tissue repair.

Nervous system

Vitamin C supports the normal function of the nervous system. Its primary role is to support the production (biosynthesis) of noradrenaline. In addition, vitamin C is involved in the modulation of neurotransmitter receptors that are needed for normal psychological functions.

Immune system

Vitamin C plays an important role in the normal function of the immune system. It supports the immune defence primarily through scavenging free radicals. Free radicals are produced when immune cells attack invading bacteria and viruses. Large amounts of free radicals are also produced during extreme physical exercise and jeopardizes the immune system. Because vitamin C is such a strong antioxidant, it counteracts the harm of free radicals.

Blood iron levels

Vitamin C supports healthy iron levels. It prevents anaemia by improving the absorption of iron from plant-based foods.

Energy levels

Vitamin C is important for sufficient energy levels and reduces tiredness and fatigue. It is important for the production of energy formation in cells.

EFSA has acknowledged the following beneficial effects as a basis for health claims:

• Vitamin C contributes to the protection of cell constituents from oxidative damage
• Vitamin C contributes to normal collagen formation and the normal function of bones, teeth, cartilage, gums, skin and blood vessels
• Vitamin C contributes to the normal function of the nervous system
• Vitamin C increases non-haem iron absorption
• Vitamin C contributes to a normal function of the immune system
• Vitamin C contributes to maintain the normal function of the immune system during and after intense physical exercise
• Vitamin C contributes to normal energy-yielding metabolism
• Vitamin C can contribute to the reduction of tiredness and fatigue
• Vitamin C contributes to normal psychological functions
• Vitamin C contributes to the regeneration of the reduced form of vitamin E

Vitamin E is a generic term covering all tocopherols and tocotrienols which qualitatively exhibit the same biological activity as α−tocopherol. Therefore, vitamin E refers to α-, β-, γ- and δ-tocopherols, plus α-, β-, γ- and δ-tocotrienols.

Antioxidant

Vitamin E is long recognised as the body´s major lipid soluble antioxidant, and thus is fundamental in maintaining the integrity and functionality of the cellular membranes of all cells of the human body. As an antioxidant, vitamin E acts within cell membranes, constructed from unsaturated fatty acids and protects the cell membranes from oxidation. In doing so, the vitamin is oxidised itself and must be ‘recycled’ back to its active form, typically by vitamin C.

Due to its role as an antioxidant, vitamin E may play a key role in the protection against conditions associated with increased oxidative stress, such as cardiovascular disease, diabetes, disorders involving chronic inflammation, cancer, and neurologic disorders.

Other effects

In addition to its antioxidant function, research demonstrated specific roles of vitamin E in signal transduction, gene expression, and regulation of cellular functions, including immune response. There is substantial evidence that vitamin E has a role in the prevention of atherosclerosis by inhibiting low density lipoprotein (LDL) oxidation and anti-inflammatory actions.
EFSA has acknowledged the following beneficial effects as a basis for health claim:
• Vitamin E contributes to the protection of cell constituents from oxidative damage

Zinc is an essential mineral that is naturally present in some foods. Zinc is involved in numerous aspects of the cellular metabolism. It is required for the catalytic activity of approximately 100 enzymes and it plays a role in immune function, protein synthesis, wound healing, DNA synthesis, and cell division. Zinc also supports normal growth and development during pregnancy, childhood, and adolescence and is required for proper sense of taste and smell. In addition, it also helps to normal cognitive functioning, vision and fertility. A daily intake of zinc is required to maintain a steady state because the body has no specialized zinc storage system.

Immune system

Zinc is involved in the regulation and maintenance of the normal activity of special immune cells. Some studies have demonstrated a relationship between zinc intake and reduction in the length and severity of a cold.

Wound healing

Because of its immune regulating mechanism, zinc is also critical in wound healing and the various stages of tissue reconstruction. When the skin is ruptured, the inflammatory process is activated and special immune cells are directed to the wound. There they remove bacteria from the wound. Wound healing also consists of growth of new tissue, and zinc is thought to have a beneficial role in new cell formation.

Bone health

Zinc also has a role in normal bone maintenance. Zinc is contained in crystals that form a bone matrix and is required to stimulate bone formation and inhibit bone decomposition. It is probable that zinc, in combination with calcium, might protect against the risk for osteoporosis.

Vision

Researchers have suggested that both zinc and antioxidants delay the progression of age-related macular degeneration and vision loss, possibly by preventing cellular damage in the retina.

The European Food Safety Authority (EFSA) has acknowledged the following beneficial effects as a basis for health claims:
• Zinc contributes to normal function of the immune system
• Zinc contributes to normal DNA synthesis and cell division
• Zinc contributes to the protection of cell constituents from oxidative damage
• Zinc contributes to maintenance of normal bone
• Zinc contributes to normal cognitive function
• Zinc contributes to normal fertility and reproduction
• Zinc contributes to normal metabolism of fatty acids
• Zinc contributes to normal acid-base metabolism
• Zinc contributes to normal metabolism of vitamin A
• Zinc contributes to maintenance of normal vision
• Zinc contributes to normal carbohydrate metabolism
• Zinc contributes to normal macronutrient metabolism
• Zinc contributes to normal protein synthesis
• Zinc contributes to the maintenance of normal hair
• Zinc contributes to the maintenance of normal nails
• Zinc contributes to the maintenance of normal skin
• Zinc contributes to the maintenance of normal testosterone levels in the blood
• Zinc has a role in the process of cell division