1) Nutrition involves macromolecules like proteins, carbohydrates, and fats that provide energy, as well as vitamins, minerals, fibre, and water. 2) Enzymes break down macromolecules and are named according to their targets, like protease for proteins. Most enzymes act in the small intestines under hormonal control. 3) The liver stores and releases glucose and fat, produces bile to break down fat, and helps detoxify the body. Too much alcohol can lead to cirrhosis of the liver.

1. Nutrition

3. Nutrition: Macromolecules Macromolecules are broken down by enzymes Enzymes are the proteins responsible for breaking down molecules in your body.

4. Nutrition In general, enzymes are named according to the chemical they act upon followed by an –ase ending. protease  proteins carbohydrase  carbohydrates lipase  lipids Nutrition: Macromolecules

5. Nutrition The majority of enzymes are active in the small intestines . Release of these enzymes is controlled by hormones . Nutrition: Macromolecules

6. Nutrition Nutrition: Liver The LIVER : • stores and releases excess glucose (glycogen and fats) • produce bile salts from cholesterol to break down fat globules to droplets in small intestines  easier for lipases to break down and lacteal absorption

7. Nutrition Nutrition: Liver The LIVER … • major organ for detoxification • a variety of enzymes that recognize uncommon molecules • recycling of old molecules

8. Nutrition Nutrition: Liver Too much alcohol consumption or infection (i.e. Hepatitis A, B, and C) can lead to cirrhosis

9. 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

10. 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

11. 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

12. 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

13. Nutrition Nutrition: Fibre Fibre is cellulose We do not have enzymes to digest cellulose. Cellulose passes through our digestive system intact , but sticks to water and cholesterol along the way.

14. 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.

15. 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

16. 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

17. 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

18. Nutrition Nutrition: Fats There are saturated fats and unsaturated fats : Saturated fats: -All fatty acids have single bonds -Usually solid at room temperature

19. Nutrition Nutrition: Fats There are saturated fats and unsaturated fats : Unsaturated fats: -Fatty acids have some double bonds -Usually liquid at room temperature

20. 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

21. 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

22. Nutrition Nutrition: Cholesterol Cholesterol: HDL = high density lipoprotein (more protein, less cholesterol) LDL = low density lipoprotein (less protein, more cholesterol)

24. Nutrition Nutrition: Regulating Sugars Regulating blood sugar: Insulin allows sugar to enter cells -lowers blood sugar levels after a meal Glucagon releases sugar from cells -raises blood sugar levels when energy is required (between meals)

25. Nutrition Nutrition: Regulating Sugars Regulating blood sugar: The liver stores sugar as glycogen -glycogen can easily be converted back to glucose by glucagon when blood sugar levels are too low -glycogen reserves can be converted to fat to be stored in cells

26. Nutrition Nutrition: Regulating Sugars Type II diabetes: Chronic high levels of blood sugar can lead to the overproduction of insulin . Over time, the cells develop insulin resistance (they stop responding to insulin). Sugar is left in the bloodstream, which causes damage to other tissues.