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Major mineralTrace mineral Calcium (Ca)Iron (Fe) Phosphorus (P)Zinc (Zn) Chlorine (Cl)Copper (Cu) Sodium (Na)Manganese (Mn) Potassium (K)Fluorine (F) Magnesium (Mg)Cobalt (Co) Iodine (I)Selenium (Se) Chromium (Cr)

 Iron is an important mineral  Deficiency in iron is the most common mineral deficiency in humans  Iron is present in haemoglobin in the blood, myoglobin in the muscles, enzyme systems in the body cells, and is also stored in the liver, spleen and bone marrow

FunctionsEffects of deficiency SourcesRDA (mg/day) Iron is necessary for the formation of haemoglobin, which carries oxygen around the body Its forms part of myoglobin which carries oxygen to the muscles It is an important part of enzyme systems that use oxygen to release energy from food Iron deficiency causes haemoglobin levels to fall, which means that there is not enough oxygen going to the body tissues It can lead to: 1.Tiredness 2.Paleness 3.Breathlessness 4.Anaemia Anaemia is a common condition in Ireland especially women Meat Meat products Chicken Cereals Eggs Pulses Green Vegetables Fish Children 10 Adolescents Adults: Males 10, f females 14 Pregnant or lactating women 15

 Definition & Cause: Anaemia is a disease caused by a shortage of haemoglobin, as a result of insufficient iron in the diet, or an inability to absorb iron  It is more common in females due to menstruation  Symptoms: Tiredness, dizziness, headaches, paleness, shortness of breath & loss of appetite

Haem ironNon-haem iron This is ferrous iron Its chemical symbol is Fe²+ It is soluble & easily absorbed Sources of haem iron include meat, meat products, chicken This is a ferric iron Its chemical symbol is Fe²+ It cannot be absorbed in the body & must be changed into ferrous iron to be absorbed Sources of non-haem iron include cereals, eggs, pulses, green vegetables, fish

Factors aiding iron absorption  Eating haem iron (because it is more easily absorbed than non-haem iron)  Eating non-haem and haem iron together increases non-haem iron absorption  Vitamin C is a reducing agent, as it changes ferric iron (Fe³+) to the more easily absorbable ferrous iron (Fe²+)  Hydrochloric acid in the stomach aids absorption by changing non-haem iron to haem iron

Factors hindering iron absorption  Phytic acid, in cereals and legumes, binds to iron, decreasing its absorption  A dietary fibre intake above 35g per day has a tendency to bind iron, decreasing its absorption  Oxalic acid, which is found in some fruit and vegetables (rhubarb & spinach), combines with iron, inhibiting its absorption  Tannins in tea, coffee & cocoa decrease iron absorption.

 99% of calcium in the human body is present in human bones  It is also found in the blood, muscles and nerves FunctionsEffects of DeficiencySourcesRDA mg/day Calcium plays a major role in the formation & development of bones & teeth Calcium is important in blood clotting Calcium is necessary for muscle contractions, normal functioning of nerves & membrane permeability Calcium is required to regulate metabolism in the cells Rickets Osteomalacia in adults Osteoporosis in the elderly Tooth decay Poor blood clotting Failure of the muscles to relax (muscular spasms) Dairy products, e.g. Milk, cheese, eggs Dark green vegetables e.g. Spinach, cabbage Canned fish, e.g. Salmon Fortified Flour Hard water Children 800 Adolescents 1200 Adults 800 Pregnant/ lactating women 1200

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Approx. 20% of Calcium intake is absorbed in the small intestine where it is bound to a specific carrier protein Factors aiding calcium absorption  Vitamin D which stimulates calcium binding protein & increases absorption  Parathormone is a hormone that controls the level of calcium in the blood (It is produced by the parathyroid gland)  Amino acids combine with the calcium salts, which are absorbed easily  Phosphorus combines with calcium to form calcium phosphate  An acid environment helps calcium absorption (eating vitamin C with calcium rich foods)

Factors hindering calcium absorption  Phytic acid, present in cereals and grains binds to calcium, preventing its absorption  Oxalic acid, present in rhubarb & spinach, binds to the calcium, preventing its absorption  Fibre binds to calcium, preventing its absorption  Excess saturated fat forms insoluble soaps with calcium, preventing its absorption  Overconsumption of soft drinks  An incorrect calcium/phosphorus ratio  Levels of oestrogen in postmenopausal women play a major role in the absorption of calcium  Tannins in tea

Zinc Function Reinforces the immune system Protects against infection Needed for:  The metabolism of carbohydrate and protein  The production of male sperm and female ova  The formation of bone tissue and healing wounds Sources Zinc from animal foods, such as meat, liver, eggs, poultry and milk, is more readily absorbed than zinc from plant foods Seafood, wheat germs, nuts, pulses, bread

Zinc Effects of deficiency Deficiency is found in those whose diet is high in refined cereals, and whose intake of animal protein is low. Deficiency can cause:  Skin problems  General tiredness  Hair loss  Prolonged healing of wounds RDA Zinc is not stored in the body so a daily intake is required  4 – 7 mg for children  7 – 9 mg for adolescents  7 – 10 mg for adults

Iodine Function Very important as it is a part of the thyroid hormone thyroxine, which is essential for normal growth and physical and mental development Also involved in maintaining metabolic rate Sources Fish, meat, milk, table salt Effects of deficiency Deficiency is rare in the Western world but it may cause:  Goitre  Cretinism  Increased incidence of miscarriage and still births RDA 150 g for adults, 90 g for children

Potassium Function Vital for the correct functioning of the heart muscles and nerves Helps protein metabolism Sources Found in nearly all foods including green veg, wholemeal products, pork, fruit (especially bananas), fruit juices, dairy products and grains Effects of deficiency Deficiency is rare but it may cause:  Diarrhoea, excessive sweating, fatique, bloating, insomnia RDA As potassium is stored in the fluids of the body cells, it is excreted, therefore a daily intake is essential  3 g for children, 3.5 g for adults

Sodium Function Needed to regulate body fluids Needed for energy release Needed for proper functioning of nerves and muscle contraction Sources Smoked fish, soy sauce, ham, bacon, olives, processed foods and table salt Effects of deficiency As sodium is found in small amounts in many foods and is particularly high in processed foods, most people have a higher sodium intake than they need. High sodium intake has been linked to high blood pressure and strokes RDA RDA met by a high intake of processed foods

VitaminRelationship with Minerals 1.Vitamin D 2.Vitamin K 3.Vitamin C 4.Vitamin B 6, B 12, Folic Acid Works in the absorption of calcium & phosphorus Works with calcium in clotting blood Works in the absorption of iron & calcium Works with iron in the formation of red blood cells

Water (H2O) Water is essential for life Two-thirds of our body is made up of water Water is the main component of blood, lymph and digestive secretions, as well as all other liquid parts of the body It is made up of hydrogen and oxygen molecules in the ratio 2:1

Water Properties Colourless, odourless and tasteless liquid Boils at 100°C and freezes at 0°C Neutral PH of 7 Excellent solvent capable of dissolving a number of substances Exists in three states: solid (ice), liquid (water), and gas (steam) Able to absorb heat and maintain it Sources Tap/ bottled water Beverages such as tea and coffee Fruit and vegetables All foods contain a certain amount of water

Water Functions Transporting nutrients, oxygen, enzymes and hormones around the body Removal of waste products from the body, e.g. from the kidneys Quenches thirst Contains the minerals calcium and fluorine Controls body temperature through perspiration Significant in the hydrolysis of nutrients during digestion Essential element of all body fluids and tissues RDA Between 2 and 3 litres per day