Nutrition
The work of Life Consumers need complex carbon compounds for energy building blocks To release energy, oxidize glucose: C6H12O6 + 6O2 ==> 6CO2 + 6H2O 686 Cal released per mole of glucose.
The work of Life What do living things do with chemical energy? 1. Mechanical work muscular contraction 2. Transport work maintain appropriate concentrations of chemicals within cells 3. Biosynthesis build large biomolecules
Metabolism Metabolism is the totality of chemical reactions in living matter. Two directions: anabolic: building up complex biomolecules catabolic: breaking down complex molecules, releasing energy
It Takes Energy To Survive For every Kg of body weight 1.0 Calorie is required every hour.
Measuring Metabolic rate A calorie is the amount of energy required to raise 1 g of water by 1 deg C. When we talk about food values we refer to them as Calories (notice the C). Which are actually kilocalories, thus 1,000 calories = 1 kilocalorie
Measuring Metabolic rate There for, 1 Calorie is the amount of energy required to raise 1 kg of water by 1 deg C.
Measuring Metabolic rate Food is also measured in joules (J) 1 calorie = 4.2 J
Daily Recommended Dose Men Women Safe Weight loss 2,300 2,000 Maintain weight 2,500 2,200 Active or gain 2,700 2,400
Like fuel for a car, the energy we need has to be blended. The blend that we require is as follows: 57% Carbohydrates (sugar, sweets, bread, cakes) 30% Fats (dairy products, oil) 13% Protein (eggs, milk, meat, poultry, fish)
1g Fat = 9 calories 1g Carbohydrates = 4 calories 1g Protein = 4 calories
Calories The General Guide to Calories provides a general reference for calories when you look at a Nutrition Facts label. This guide is based on a 2,000 Calorie diet. Eating too many Calories per day is linked to overweight and obesity
Nutrients
Carbohydrates Make up 5% of the body mass Body s main fuel source Cells release the energy by oxidising glucose Mostly from starch, not sugar
Carbohydrates Unprocessed carbohydrates Starch Cellulose Processed carbohydrates Sugar Flour
Carbohydrates Dieticians generally recommend is 300g of carbohydrates.
Lipids Make up 10% of our body mass Form an essential part of cell structure Long term energy storage Insulation Protection
Are fats bad for you? NO they help carry and store vitamins A,D,E, and K
Saturated Fats Saturated fats and trans fats are often called "bad fats" because they raise cholesterol and increase a person's risk for developing heart disease. Both saturated and trans fats are solid at room temperature
Unsaturated Fats These are fats that are liquid at room temperature. Unsaturated fats are often called "good fats" because they don't raise cholesterol levels as saturated
Cholesterol Lipids also contain cholesterol From eggs and meat Too much cholesterol can be linked to heart disease
Lipids Dieticians generally recommend that no more than 65 grams come from fat.
Proteins Make up 18% of body mass Animal products All cells contain protein Growth and repair Enzymes
Proteins Dieticians generally recommend a maximum intake of 70 g per day Protein-deficiency disease called kwashiorkor are common in poorer countries.
Minerals Cellular functions Body structure Haemoglobin
Minerals Mineral deficiency diseases Rickets poor bone development Anaemia can t make haemoglobin
Minerals Calcium Phosphorus Sodium Chlorine Magnesium Iron -teeth and bones - teeth, bones and DNA - body fluids - body fluids - bones and cells - haemoglobin
Vitamins Organic substances required in minute amounts to maintain health Help with the process of cell respiration, making chemicals in the retina, sticks cells lining together, helps bones absorb calcium and phosphate
Vitamins A - eye & epithelia - susceptibility to disease - poor night vision B - cell respiration - low energy C - skin, immune system - scurvy, poor wound healing, immunity D - bones, regulation - rickets (poor bones)
Vitamins Vitamins A and D are fat soluble, ingested in fat and oil Vitamin C is water soluble and present in other materials