Chapter 10: Food For Life 10.1: Assessing Nutrients Page 198 Science 14 and 10-4 with Mrs. M

This week Today 10.1 and 10.2 Tuesday 10.3 digestive system Wednesday 10.4 Thursday Review – Food log due (One day log) Friday Test

10.1: Assessing Nutrients How do diet and lifestyle affect circulatory and digestive systems?

Food influences body functions You need nutrition in order to live

Nutrition Nutrition is a branch of science that studies foods and how the body uses them Nutrients are substances found in foods The nourishment and energy help the body to maintain its cells, tissues, and organs, and to support growth and development

Malnutrition Malnutrition occurs when essential nutrients are missing from a diet. It can occur when people eat too little. It can also occur if people eat enough volume but make poor food choices and are therefore missing important nutrients

Malnutrition Malnourished people often suffer from high levels of sickness and disability They also have shorter life spans Those who lack an adequate supply of food may die from starvation Children who lack proper nutrients may not grow properly and may suffer from brain damage

What nutrients do we need? Carbohydrates Proteins Fats Vitamins Minerals Water

What nutrients do we need? Carbohydrates: in the form of sugars and starches are the primary source of energy for your body

What nutrients do we need? Proteins: build body tissue, regulate chemical activity, and supply energy

Nutrients Fats: are stored in the body for use as an energy source when carbohydrates are in short supply

Nutrients Vitamins: are organized according to whether they can be absorbed in fat or water Minerals: help carry out life functions. Minerals include calcium, phosphorus, magnesium, iron, and iodine Water: is essential for life because it is used in every life function. The water you take in through food and drink needs to balance the water that is eliminated from your body.

Canada’s Food Guide

Food Pyramid

10.2 Analyzing Diets Diet: the amount and type of food you eat Mixed diet: eating a wide variety of foods Canada’s Food Guide classifies food into four different groups

How much food do you need? The amount of food you need depends on: – Your age – Your body size – Your activity level – Your gender

Five guidelines Eat a variety of foods Eat a lot of whole grain cereals, breads, fruits, and vegetables Choose low fat dairy products, lean meats, and foods prepared with little or no fat Participate in regular physical activity Limit the intake of salt, sugar, alcohol, and caffeine

Food Labels Advertising Preparation directions Nutrition information – Ingredients – Percentage of Recommended Daily Intake

Different types of diets Vegetarian Vegan Raw food Paleolithic Fads

Cleanses To give your body a break and deal with excess toxins May feel more fatigued during a cleanse

Lab Liver friendly foods

Liver-friendly foods Apples Grapefruit Broccoli

Apples Stimulate saliva to prevent tooth decay Detox liver Fibre – Controls weight – Avoid hemorrhoids – Prevent gallstones – Reduce cholesterol for a healthier heart

Grapefruit Detoxify liver Strengthen immune system Reduce risk of kidney stones Boost metabolism Fight gum disease Prevent cancer Reduce stress Antioxidant Vitamin C

Broccoli Detoxify liver by stimulating it with a toxin Reduce osteoarthritis Reduce cancer risk

10.3 Digestive System: Mining the Nutrients Page 207 Mechanical Digestion: teeth and stomach break food into small pieces Chemical Digestion: chemicals known as enzymes break down food particles Absorption: molecule-sized products move into blood stream

Digestive System Food = chemical energy Body uses nutrients for energy, growth, and repair Different nutrients are digested in different areas

Location of Digestion carbs: saliva, small intestine proteins: stomach fats: small intestine water and chemicals: absorbed from stomach and in large intestine More on nutrition in Chapter 10 carbohydrates (sugars and starches) proteins fats vitamins minerals water Nutrients

Digestive System Mouth – mechanical digestion and saliva Esophagus – Transport by peristalsis Stomach – Stomach acid for protein digestion Small Intestine – With help from the pancreas, bile duct and gall bladder – Absorption of nutrients by microvilli Large Intestine – Final absorption of nutrients and water

Digestion: Mouth Teeth for mechanical digestion Saliva for chemical digestion of starches (carbohydrates)

Mouth Chewing: mechanical digestion Saliva contains amylase, an enzyme that breaks down carbohydrates Creates a bolus to be swallowed Digestive System

Esophagus Transport Peristalsis Digestive System

Stomach Sphincters Gastric juice containing enzymes and acid Hydrochloric acid (HCl) is very strong acid Digestive System

Digestion: Stomach Moves and mixes contents for mechanical digestion Mixes food with gastric juices (stomach acid) to form a pasty fluid Enzymes digest proteins to amino acids

Small Intestine Duodenum where stomach acid is neutralized Digest carbs, proteins, and fats Digestive System

Digestion: Small Intestine Enzymes for chemical digestion only Absorption of nutrients by microvilli

Small intestine Carbohydrates: enzymes further break down carbohydrates into sugars. These sugars are in a form that can be absorbed as the liver and pancreas neutralize the gastric juices Protein: enzymes split the proteins into simpler components (amino acids) into the bloodstream Fat: the liver produces bile which breaks fat into smaller particles. Enzymes from the pancreas can digest these smaller particles. Then fats can be absorbed

Large Intestine Absorption of water, vitamins, minerals Storage then elimination/excretion of waste Feces are mostly dead bacteria and undigested food, like fiber Digestive System

Digestive System Summary: Mouth – mechanical digestion and saliva Esophagus – Transport by peristalsis Stomach – Stomach acid for protein digestion Small Intestine – With help from the pancreas, bile duct and gall bladder – Absorption of nutrients by microvilli Large Intestine – Final absorption of nutrients and water

10.4 The Role of Diet What role does diet play in your life?

Evaluate Your Choices Do you think you eat a healthy diet? Is your diet balanced? Do you skip meals?

Choosing too many fats Your body has to work harder to digest fats Excess fats in your digestive system may cause you to feel uncomfortable or to throw up High fat diets can cause fatigue and lack of energy Cholesterol from fatty foods blocks arteries Over time, fats cause weight gain

Atherosclerosis Bad cholesterol LDL Good cholesterol HDL Plaque that blocks the arteries Bad for health Can cause stroke and heart attack

Saturated fats Saturated fats are BAD Trans-fats are sometimes bad Unsaturated fats are GOOD

What is healthier? Burger, fries, milkshake Spaghetti, salad, glass of milk

This or That Trivia

White Meat or Dark Meat

French fries or Fried Potatoes

Fruit Punch or Cranberry Juice

Fruit Cup or Fresh Fruit?

Butter or Margarine?

Debatable! … Just reduce your intake of any butter or margarine