Nutrition: Macromolecules Macromolecules are broken down by enzymes Enzymes are the proteins responsible for breaking down molecules in your body.
Nutrition In general, enzymes are named according to the chemical they break-down followed by an –ase ending. protease proteins carbohydrase carbohydrates lipase lipids Nutrition: Macromolecules
Nutrition The majority of enzymes are active in the small intestines . Release of these enzymes is controlled by hormones . Nutrition: Macromolecules
Nutrition Nutrition: Carbohydrates Carbohydrates are the body's main source of energy . Can be single molecules called monosaccharides . or chains of molecules called polysaccharides .
Nutrition Nutrition: Carbohydrates Excess carbohydrates are stored by the body as glycogen and (if too many) body fat . Complex carbohydrates (very large polysaccharides) are the healthiest and give a "full" for feeling longer. Glycogen. Each dot is a sugar molecule.
Nutrition Nutrition: Proteins - The average human is 3% nitrogen by mass, and most of this is N is found in protein . - Most abundant in animal products . - Also found in grains , legumes , and nuts .
Nutrition Nutrition: Fats Fats are made of fatty acids and glycerol groups . Fatty acids have several chemical bonds between hydrogen and carbon atoms, making them rich in energy. 1g fat = 9 Calories 1g carb = 4 Calories 1g protein = 4 Calories 1g alcohol = 7 Calories
Nutrition Nutrition: Fats Fatty acids and glycerol can form the following combinations: Triglyceride: 3 fatty acids + 1 glycerol Diglyceride: 2 fatty acids + 1 glycerol Monoglyceride: 1 fatty acid + 1 glycerol
Nutrition Nutrition: Fats There are saturated fats and unsaturated fats : Saturated fats: -All fatty acids have single bonds -Usually solid at room temperature Unsaturated fats: -Fatty acids have some double bonds -Usually liquid at room temperature
Nutrition Nutrition: Fats There are saturated fats and unsaturated fats : Saturated fats: -All fatty acids have single bonds -Usually solid at room temperature
Nutrition Nutrition: Fats There are saturated fats and unsaturated fats : Unsaturated fats: -Fatty acids have some double bonds -Usually liquid at room temperature
Nutrition Nutrition: Fats Some fatty acids are essential : Essential fatty acids: -Essential fatty acids are ones that our bodies need but can not make -Must be eaten, are associated with good heath and prevention of heart disease
Nutrition Nutrition: Cholesterol Cholesterol: -Essential to cell membranes , steroids , nerve insulation , fat digestion ( bile ), and produces vitamin D -Body manufactures ~2/3 of cholesterol required; ~1/3 of cholesterol acquired through the diet
Nutrition Nutrition: Cholesterol Cholesterol: -Cholesterol CANNOT dissolve in water, so it must be transported in the blood in packages known as lipoprotein -lipoproteins are complexes of lipids , cholesterol , and proteins .
Nutrition Nutrition: Cholesterol Cholesterol: HDL = high density lipoprotein (more protein, less cholesterol) LDL = low density lipoprotein (less protein, more cholesterol)
High levels of LDL are associated with a higher risk of heart disease
HDL helps reduce bad cholesterol in the blood.
HDL = “ good ” cholesterol
LDL = “ bad ” cholesterol
Nutrition Nutrition: Vitamins Vitamins are organic compounds which the body needs in small amounts . • essential for enzyme activity / cellular function • consumed through diet or produced though beneficial bacteria
Nutrition Nutrition: Vitamins 2 types: 1) water soluble – vitamin Bs and C, folic acid • easily removed from the body • easily removed during cooking 2) fat soluble – vitamin A, D, E, K • not easily removed from body do not need to consume regularly
Nutrition Nutrition: Minerals Minerals are inorganic compounds (non-carbon- containing) which the body needs in small amounts . • essential for enzyme activity / cellular function • consumed through diet • Ex. calcium , phosphorus , potassium , iron , zinc
Nutrition Nutrition: Minerals If you are getting enough minerals through your diet, should you still take multivitamins / multiminerals ? No! Some minerals prevent other minerals from being absorbed optimally
Nutrition Nutrition: Fibre Fibre is cellulose, a polysaccharide from plants. We do not have enzymes to digest cellulose. Cellulose passes through our digestive system intact , but sticks to water and cholesterol along the way.
Nutrition Nutrition: Fibre Choose 100% whole wheat products. Vegetables and fruit have some fibre as well. We should all consume ~30g of fibre a day.