– Všetko čo študent potrebuje
Sobota, 27. novembra 2021
Dátum pridania: 18.04.2003 Oznámkuj: 12345
Autor referátu: mimmi
Jazyk: Angličtina Počet slov: 4 515
Referát vhodný pre: Stredná odborná škola Počet A4: 16.6
Priemerná známka: 2.96 Rýchle čítanie: 27m 40s
Pomalé čítanie: 41m 30s

Vitamins are organic substances, which the human body need perforce, but it is not able to produce them itself. So they get into the organism like food, either like ready vitamins or like so-called provitamins, which became efficient not until the metabolism. Vitamins do not provide the organism neither energy, they are nor building material for tissues, even though they are irreplaceable for life and health. Vitamins take part in full scale of chemical processes in a lot of systems of human organism. Most of them partake (like the part of enzymes – accelerators of biochemical reactions in cells) on important processes of metabolism, they are essential for keeping the normal bodily functions and for processes leading to the building up of new tissues. The human takes in and needs only small amounts of vitamins. The need of most of them we express in thousandth (mg) or millionth (µg) of grams. It is important to ensure their input, in order not to lead to the formation of diseased utterance of their deficiency. The reduced input of vitamins adversely affects the function of organism, its tenability, physical efficiency or psychical abilities (concentration, learning…). The commended daily input of eatables is often individually different. It depends on the sex, age, physical and psychical overcastting. The larger need have hardworking people, pregnant or nursling women (the part of vitamins is by the circulation or maternal milk needed for the foetus or infant), children and teenagers (quick growth), ill people, reconvalescents and older people.

Today, the quality of our diet by the merit of changes and progress in well-balanced nutrition is mostly on sufficient level. Even though, the difference between today and past: nowadays there are almost no pure forms of total deficiency of certain vitamin – avitaminosis, but it leads only to partial reduction of amount of vitamin in body – hypovitaminosis. Mostly there are taken in reduced form vitamins, which are found in vegetables (mainly vitamin C and vitamins of group B). The frequent reason of deficiency of these vitamins is the lack of fresh fruit, vegetables and whole grain products. Lots of vitamins could be also lost during their modification in production, unsuitable storage and by not sparing kitchen pacing.
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