The EAT WELL Plate
Canada s food guide
Food pyramid
Importance of Nutrition Energy for body metabolism (nerve impulses, contraction of muscles, repair and replacement of cells Raw materials for building blocks of cells (proteins for muscles, calcium for bones, fats for cell membranes)
Essential Nutrients Macronutrients: nutrients taken in large amounts daily, provide energy: carbohydrates, proteins, fats Micronutrients: minerals, vitamins Water is essential for survival!
Macronutrients
Carbohydrates major sources of energy, quick energy source organic molecules: C, H, O Monosaccharide (C6H12O6 ) Disaccharide (C12H22O11 ) Polysaccharide
Monosaccharides- simple sugars fructose (in fruits, honey) galactose (in milk) glucose (in starch) all 3 forms have the same chemical formula C6H12O6 but in different arrangements dehydration synthesis or condensation removing a water molecule to combine 2 monosaccharide molecules forming a disaccharide
Disaccharides glucose + glucose maltose + water ** hydrolysis can break maltose easily into two glucose molecules
Disaccharides glucose + fructose sucrose + water *sucrose : common table sugar hydrolysis can break sucrose easily into glucose and fructose
Disaccharides glucose + galactose lactose + water *lactose: sugar in milk
Polysaccharides- Starch Stored in grains and vegetables
Polysaccharides- Glycogen made by animals excess glucose is converted to glycogen by hormone insulin and stored in the liver can be converted back by hormone glucagon when the blood sugar level is low
Polysaccharides- Cellulose In plant cell walls not digested in the human intestine, but provides roughage in the intestine for waste elimination
Fats Make up phospholipid bilayer in the cell membrane (contain phosphates, lipids, cholesterol) Surround and protect vital organs and joints, fats underneath skin insulate body Organic molecules: C, H, O with different ratios from carbohydrates
Fats - structure triglyceride = a 3-C glycerol molecule + 3 fatty acids (long chain of C s with an acid group at the end) Unsaturated fat
Saturated vs. Unsaturated Saturated fats: all the carbon branches are filled with hydrogen, solid at room temp. animal fat, butter, lard, hard margarines (saturated artificially) Unsaturated fats: not all carbon branches are filled with hydrogen, liquid at room temp. vegetable oil, nut oils, some fish oils, some margarines
Phospholipid Bilayer Cell Membrane Hydrophilic head (phosphate + nitrate + glycerol) and hydrophobic tail (2 fatty acids) Hydrophilic water loving Hydrophobic water fearing
Phospholipid bilayer
Cholesterol soft, waxy lipid in body cells, in arteries and veins, on cell membranes, insulate nerves, produce vitamin D, bile acids and hormones, rich in meat, shellfish, whole-milk products, eggyolks
Lipoprotein contains both proteins and lipids (phospholipids) on the outside transport fats (triglycerides) and cholesterol in waterbased bloodstream
Proteins Provide structure within the body, muscles, skin, nails, hair, organs, cells membrane protein channels, antibodies and enzymes Organic molecules, contain C, H, O, and N (text p. 15) Polypeptides are broken down to dipeptides and amino acids with the help of digestive enzymes
Proteins All proteins are built from a set of 20 amino acids 8 of them are not made in the body, so must be obtained from food, therefore called essential amino acids a complete protein= protein that is made up of the 8 essential amino acids (in meat, legume, milk, egg, cheese, whole grain)
Micronutrients Vitamins + Minerals
Vitamins Serve as coenzymes (make enzymes function), help tissue growth, defense against diseases Fat- soluble: K, E, D, A (eyes and skin) Water-soluble: B, C (antioxidant, resist disease), excess vitamins are removed in the urine K and B (body metabolism, antibody) are produced in the intestines Body can produce D when exposed to sunlight vitamins A, B1, B2, C, D, folic acid, niacin, E, K?
Minerals Inorganic, do not contain carbon Help in chemical reactions, help build bones and cartilages, hormones, Ca- bone formation, nervous signals P-bone formation, build cell membrane, nucleic acids, ATP K- nerve impulse Na- nerve impulse, osmotic balance Fe- hemoglobin synthesis (red blood cells) I- thyroid hormone Cl - water balance, Zn- enzyme synthesis, growth, Se tissue elasticity, Cu-hemoglobin synthesis