Hellenic Vitamins & Trace elements Food Vitamin B1 (Thiamine) Authority Directorate of Nutritional Policy and Research February 2008

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1 Hellenic Vitamins & Trace elements Food Vitamin B1 (Thiamine) Authority Directorate of Nutritional Policy and Research February 2008 IN GENERAL Thiamine is a water soluble vitamin. Thiamine was the first vitamin identified, in 1926 by Jansen & Donath, who had been working with rice bran extract for a treatment of the beriberi disease. INTAKE Thiamine is found in a wide variety of animal and vegetable products, but in relatively low concentration levels (lower than 0.5mg /100g of food). Significant sources of thiamine are lean pork meat, legumes and the germ of cereal. FUNCTIONS Thiamine is mainly involved in the following normal functions of the body: Promotion of glucose deconstruction along with vitamins of the B complex resulting in production of energy and Contribution to the health of muscle and nervous tissues. Thiamine is relatively easily absorbed, but absorption decreases considerably when thiamine is taken in orally in quantities exceeding 5mg. It is worth mentioning that its metabolism is especially sensitive to excess alcohol consumption since its absorption is decreased and its excretion is increased. A balanced and varied diet is capable of covering the usual needs of the human body in thiamine. Thiamine intake needs vary according to population group (e.g. children, people with health problems, pregnant women, breastfeeding women).

2 Hellenic Vitamins & Trace elements Food Beta carotene (Pro vitamin A) Authority Directorate of Nutritional Policy and Research February 2008 One of the most important carotenoids is beta carotene, namely a fat soluble vitamin which isa pro vitamin of vitamin A (6μg of beta carotene equal 1 μg of vitamin A). The food groups which constitute the main sources of beta carotene are yellow and orange vegetables (such as carrots), oranges, tomatoes, leafy green vegetables (such as spinach, chicory, broccoli, cabbage) and yellow fruit (such as mangos, melons and apricots). Beta carotene is absorbed by the human body in ways that vary according to the time of year. Moreover, the content of beta carotene in foods is affected by the influence of light as well as temperature. FUNCTIONS The concentrations of vitamin A which are produced in the body by beta carotene are stored in the liver and, when appropriately activated, are released in the plasma. Absorption of beta carotene, which varies from 10% to 90%, depends on many factors. Absorption is linear for intakes up to mg, but it is considerably decreased for larger quantities. A balanced and varied diet is capable of covering the usual needs of the human body in beta carotene. Beta carotene intake needs vary according to population group.

3 Hellenic Food Authority Directorate of Nutritional Policy and Research February 2008 Carbohydrates What are they? Carbohydrates are composed of sugars. Based on the number of sugars composing their molecule they are classified into: 1 Simple carbohydrates (monosaccharides and disaccharides) and 2 Complex carbohydrates (oligosaccharides and polysaccharides). Carbohydrates Oligosaccharides (1 sugar (3 9 molecule) sugar molecules) Simple Complex Monosaccharides Maltodextrines Glucose Fructose Polysaccharides (10 or more sugar molecules) Starch Disaccharides (2 sugar molecules) Sucrose (sugar) Cellulose Lactose Pectin Maltose Sugar sources Fruit, vegetables & honey are good sources of glucose and fructose. Milk contains lactose. Maltodextrins are to be found in barley, while foods rich in starch are bread, pasta, rice, potatoes and legumes.

4 Hellenic Minerals Food Authority Directorate of Nutritional Policy and Research February 2008 Minerals are chemical elements which are necessary for normal functions of the body. They are divided in macro trace elements, which are necessary in relatively large quantities, and in trace elements, that are necessary in slight quantities. Where they can be found Meat Cereal Fish Milk & dairy products Vegetables Salt Fruit Dried nuts

5 Hellenic Proteins Food Authority Directorate of Nutritional Policy and Research February 2008 What are they? Proteins are large organic molecules which are composed of amino acids, appropriately bound to each other. Amino acids are the basic components of proteins. 20 different amino acids, which are composed by most plants, can be found in nature. In mammals, amino acids are classified into: 1 essential ones, which cannot be synthesised by the body during metabolism and consequently must be taken in through food and 2 non essential ones, which are produced internally in the body through metabolism of other proteins. High biological value proteins are the ones whose molecule is basically composed of essential amino acids Low biological value proteins on the other hand are the ones whose molecule has a low rate of essential amino acids Protein Sources For high biological value protein intake, choose: meat, poultry, fish, eggs, milk, cheese and yogurt. Vegetables, greens, cereal are sources of low biological value proteins.

6 Hellenic Vitamins & Trace elements Food Retinol (Vitamin A) Authority Directorate of Nutritional Policy and Research February 2008 IN GENERAL Vitamin A, also known as retinol, is a fat soluble vitamin which constitutes an essential nutrient for most mammals. Its daily intake is not necessary, as it is stored in the body for future use. It is resilient to light and environmental temperatures. Significant sources of vitamin A are the liver, cod liver oil, egg yolk, fatty fish and dairy products. Vitamin A is expressed in retinol equivalents (RE), where 1 RE equals 1μg of retinol. A balanced and varied diet is capable of covering the usual needs of the human body in Vitamin A. Vitamin A needs vary according to population group (e.g. pregnant women, people with health problems). Pregnant women are advised to refrain from consuming liver, since it contains large quantities of vitamin A and its overconsumption may lead to exceedance of the Tolerable Upper Intake Level.

7 Hellenic Food Authority Directorate of Nutritional Policy and Research February 2008 Vitamins & Trace elements Vitamin B12 Vitamin B12 is a water soluble vitamin that belongs to the B complex and daily intake of which is necessary. Vitamin B12 is composed of microorganisms that enter the food chain through products of animal origin. So, significant sources for its intake are dairy products, fish, red meat and eggs. People consuming large quantities of food such as liver and sardines receive large quantities of vitaminb12. A balanced and varied diet is capable of covering the usual needs of the human body in vitamin B12.

8 Hellenic Vitamins & Trace elements Food Riboflavin (Vitamin B2) Authority Directorate of Nutritional Policy and Research February 2008 IN GENERAL Riboflavin is a water soluble vitamin that belongs to the B complex and daily intake of which is necessary. As it is destroyed under the influence of ultraviolet radiation (UV), food which contains riboflavin must be kept away from direct exposure to sunlight. Riboflavin is found in most foods, in all plant and animal cells, but few of those are notable sources of it. Liver is a very good source of riboflavin, as it contains more than 2mg/100g. Other significant sources are milk, egg white, fish eggs and leafy green vegetables (such as spinach, chicory, broccoli and cabbage). A balanced and varied diet is capable of covering the usual needs of the human body in Riboflavin.

9 Hellenic Food Authority Directorate of Nutritional Policy and Research February 2008 Vitamins & Trace elements Vitamin B12 Vitamin C is a water soluble vitamin that belongs to the B complex and daily intake of which is necessary. Sources of vitamin C are citrus fruit, kiwi, soft fruit (such as strawberries, berries, raspberries), leafy green vegetables (such as spinach, chicory, broccoli, cabbage), green peppers and animal organs, such as liver or kidneys. During the cooking of food a portion of vitamin C contained in it is lost as a result of its solution in water and its oxidation. A balanced and varied diet is capable of covering the usual needs of the human body in vitamin C. Vitamin C intake needs vary according to population group (e.g. pregnant women, children, people with health problems, breastfeeding women). Vitamin C absorption decreases when it is received in large quantities. Consequently, intake of more than 1g/day does not contribute to vitamin C increase in the body, while it poses an increased risk for manifestation of gastroenteric disorders.

10 Hellenic Food Authority Directorate of Nutritional Policy and Research February 2008 Vitamins & Trace elements Vitamin B12 Vitamin D belongs to fat soluble vitamins. Its daily intake is not necessary, as the amount of vitamin not used by the human body is stored for future use. Few foods contain vitamin D. Natural sources of vitamin D are: Fatty fish (such as salmon), liver, cod liver oil, egg yolk, milk and some types of cereal. A balanced and varied diet is capable of covering the usual needs of the human body in vitamin D. Vitamin D intake needs vary according to population group (e.g. newborn children, the elderly). People who cover their skin often, the elderly, people living in areas with few hours of sunshine compose a smaller quantity of vitamin D.

11 Hellenic Food Authority Directorate of Nutritional Policy and Research February 2008 Vitamins & Trace elements Vitamin B12 Vitamin E is a fat soluble vitamin. Precursor compounds of vitamin E are tocopherols, the most significant of which is α tocopherol. The primary sources of vitamin E are vegetable oils, cereal and dried nuts, while it is also found in smaller quantities in fruit, vegetable and meat (mainly in the fatty parts). A balanced and varied diet is capable of covering the usual needs of the human body in vitamin E. Vitamin E intake needs vary according to population group (e.g. children, people with health problems). The Tolerable Upper Intake Level for Vitamin E is 300mg/day.