nutrition & digestion
DESCRIPTION
Nutrition & Digestion. Lesson 1. Good nutrition enhances your quality of life & helps prevent disease. Nutrients: Substances in food that your body needs to grow, repair itself, and supply you with energy. The Importance of Nutrition. Nutrients in our food. Carbohydrates. Proteins. Fats. - PowerPoint PPT PresentationTRANSCRIPT
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Nutrition & DigestionLesson 1
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The Importance of Nutrition
Good nutrition enhances your quality of life & helps prevent disease.
Nutrients: Substances in food that your body needs to grow, repair itself, and supply you with energy.
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Nutrients in our food
Carbohydrates
Proteins Fats
MineralsVitamins Water
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CarbohydratesCarbohydrates are the sugars and starches found in food. They are the major source so energy for you body. They can be divided into two types.
Simple Carbohydrates (Sugars)
Complex Carbohydrates (Starches)
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Simple CarbohydratesSimple Carbs = sugars like sucrose used to sweeten many foods, or lactose in milk.
Simple carbohydrates are absorbed rapidly. This increases the chance of sugar converting to fat. Foods like cake, pastry, biscuits, chocolate to name a few contain lots of "empty" calories. Because our cells usually do not require that amount of energy at that time, the sugar must either be converted to glycogen ( sugar storage within cells ) or converted to fat.
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Complex CarbohydratesComplex Carbs: Starches found in whole grains. Foods like potatoes & beans. These carbs take longer to break down and absorb, this gives you more time to use the energy they provide through exercise. Complex carbs are usually found in foods that provide a variety of nutrients.
An indigestible complex carbohydrate that is found in parts of vegetables, fruits, & whole grains is called fiber. (Fiber helps move food through the digestive process)
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Glycemic Index
•The glycemic index or GI describes this differences in carbohydrates by ranking them according to their effect on our blood glucose levels. Studies are showing Choosing low GI carbs - the ones that produce only small fluctuations in our blood glucose and insulin levels - is the secret to long-term health reducing your risk of heart disease and diabetes and is the key to sustainable weight loss.
•High glycemic index foods generally make blood sugar levels higher. In addition, people who eat a lot of high glycemic index foods tend to have greater levels of body fat, as measured by the body mass index (BMI). High BMIs are linked to obesity, heart disease, and diabetes.
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Proteins Proteins: Nutrients that help build
and maintain body cells & tissue.
During major growth periods, such as infancy, & teen years, the body builds new cells & tissue from the amino acids in proteins.
A complete protein is a protein that contains all of the essential amino acids. All animal proteins are complete, including red meat, poultry, seafood, eggs, and dairy.How do vegetarians or those allergic to dairy
products get their complete proteins?
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Fats There are numerous types of fat.
Your body will store excess calories in fat cells. Some fats are found in plants (tropical oils) and animals and are known as dietary fat. Dietary fat can provide your body with energy. Fat is essential to your health because it supports a number of your body's functions. Some vitamins, for instance, must have fat to dissolve and nourish your body. Can you find similarities between fatty foods
and alcohol, drugs, or other risky behaviors?
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The Good(Unsaturated)
The Bad(Saturated)
The Ugly(Trans Fats)
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Unsaturated Fats This is a type of fat found
in a variety of foods and oils. Studies show that eating foods rich in unsaturated fats improves blood cholesterol levels, which can decrease your risk of heart disease. Research also shows that these types of fats may benefit insulin levels and blood sugar control, which can be especially helpful if you have type 2 diabetes.
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Saturated FatsThis is a type of fat that
comes mainly from animal sources of food. Saturated fat raises total blood cholesterol levels and low-density lipoprotein (LDL) cholesterol levels, which can increase your risk of cardiovascular disease as well as Type 2 Diabetes.
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Trans Fats This is a type of fat that occurs
naturally in some foods, especially foods from animals. But most trans fats are made during food processing through partial hydrogenation of unsaturated fats. This process creates fats that are easier to cook with and less likely to spoil than are naturally occurring oils. Not only do trans fats raise LDL (bad cholesterol) but they also strip the body of HDL (good cholesterol).
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Minerals Minerals: Substances that the
body cannot manufacture but that are needed for forming healthy bones & teeth, and regulating many vital body processes.
Water is the most vital mineral to the body. It helps in the following…
Carries wastes form your cells. Lubricates your joints. Absorbs nutrients Helps eliminate wastes Helps maintain normal Body Temp
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Minerals Continued…There are many
other important minerals such as….
CalciumPhosphorusMagnesium Iron
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VitaminsVitamins:
Compounds that help regulate many vital body processes, including digestion, absorption & metabolism.
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Assignment Step 1: Students will visit the My Pyramid web site at
www.choosemyplate.gov Step 2: Click the interactive tools link on the left side of the
page. Step 3: Click Daily Food Plan under interactive tools. Step 4: Enter personal information in the spaces provided. Step 5: Now that you have your Daily Food Plan you can click
“Click Here to view and print a PFD” link on the right side of the screen.
Step 6: Print 2 copies of the page, one for you and one for the teacher.
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Digestive ProcessThe human digestive system is a complex series of organs
and glands that process food. In order to use the food we eat, our body has to break the food down into smaller molecules that it can process; it also has to excrete waste. Click on the topics below to learn more about digestion..
Digestion: DefinitionDigestion Anatomy (parts)
Digestion Process
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Digestion The process of breaking down food in the stomach and intestines into substances that can be used by the body.
•The process of breaking down food into substances that can be used by the body.
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Anatomy of the Digestive System
•Mouth•Esophagus•Stomach•Liver/Pancreas/Gall Bladder•Small Intestine•Large Intestine•Rectum
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Digestive ProcessesStep 1 (Mouth): Food that enters the mouth is mechanically broken down by the chewing process and chemically broken down by enzymes in saliva.
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Digestive ProcessesStep 2 (Esophagus): After being chewed and swallowed, the food enters the esophagus. The esophagus is a long tube that runs from the mouth to the stomach. It uses rhythmic, wave-like muscle movements (called peristalsis) to force food from the throat into the stomach.
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Digestive ProcessesStep 3:(The Stomach) The stomach is a muscular organ that secretes acid and enzymes to break down foods.. The stomach muscles contract periodically, churning food to enhance digestion. The pyloric sphincter is a muscular valve that opens to allow food to pass from the stomach to the small intestine.
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Digestive ProcessesStep 4: (Small Intestine) The small intestine is a 20 foot long tube where foods pass through to be broken down even further. It’s also the area where nutrients are absorbed from the foods we eat.
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Digestive ProcessesStep 5: (Liver, Pancreas, Gall bladder) While food travels through the small intestine bile produced by the liver and stored in the gallbladder continue, to break down food with the help of enzymes released by the pancreas
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Digestive ProcessesStep 6: (Large Intestine) After food passes through the small intestine it enters the large intestine. This large tube portion of the digestive system is most responsible for absorption of water from the indigestible residue of food. Indigestible food finally reaches the lower portion of the large intestine called and colon and then passed out of the body through the rectum.
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MetabolismMetabolism is the rate at which your body uses energy, or, burns calories. Your resting metabolism measures the number of calories required to keep your body functioning.
Someone with a high metabolic rate is able to burn calories more efficiently than someone with a slower metabolic rate. The less efficient your body is at burning calories the more you will store as fat.
There are many heredity & environmental factors that effect your metabolism.
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CaloriesCalories are ENERGY that fuel our bodies; much like gasoline fuels our cars. The number of calories in food is a measure of how much potential energy that food possesses.
Most adult bodies needs at least 1000 to 1400 calories a day to have enough energy to fuel key organs like the brain, heart, and lungs. This minimum number of calories is called your resting metabolic rate (RMR) and it varies greatly depending on age, sex, weight, and muscle mass. In order to have enough energy to live your day and be active you need more energy than what's required from your resting metabolic rate (RMR). This extra energy typically amounts to about 400 to 600 additional calories per day which is the energy you need to move versus just lying still all day.
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CaloriesNutrients that Provide Energy: Fats, Proteins and Carbohydrates all provide energy to our body and have caloric measurement.
Carbohydrates: 1 gram = 4 calories Fats: 1 gram = 9 calories Protein: 1 gram = 4 calories
In order to maintain body weight, the calories we eat need to correlate with the calories we burn. When you burn more than you eat, you will loose weight. When you consume more calories than you burn, you will gain weight. Calories that are not burned are turned into body fat and stored. 3,500 extra calories consumed = 1 pound of body fat. If you burn 3,500 more calories than you eat, your body will convert 1 pound of stored fat into energy.
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What influences your food choice?It’s important to understand the difference
between your physical need for food and your desire for food.
Hunger: An unlearned, natural physical drive that protects you from starvation.
Appetite: A desire to eat. (Not a need)
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What causes you to eat?Emotional needs
sometimes cause us to eat, like when we
are stressed or depressed.
Environmental factors like your family &
peers.
Convenience and cost also plays a role in
what you eat. (Eating less healthy food
because it’s fast and doesn’t cost a lot.)
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Guidelines for Healthy Eating
Lesson 3
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Age Sedentary Active
Females14-18 1,800 2,40019-30 2,000 2,40031-50 1,800 2,20051+ 1,600 2,200
Males14-18 2,200 3,20019-30 2,400 3,00031-50 2,200 3,00051+ 2,000 2,800
Daily Calorie Intake Range
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Understanding Food LabelsBeing able to
read and understand
food labels is an important
step in understanding
what your putting into your body.
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CholesterolCholesterol is a waxy
fatty substance that circulates in blood.
Your body uses small amounts of it to manufacture cell
membranes & bile, which helps to digest
fats.
Excess blood cholesterol is deposited
in arteries, including the arteries of the
heart. This increases the risk of heart
disease.
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Food & Healthy LivingLesson 4
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Food PoisoningFood Poisoning can result from eating food
contaminated with pathogens (disease causing organisms), or poisonous chemicals.
Many times the contamination can’t be seen, smelled, or tasted.
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Causes & Symptoms of Food Poisoning
According to the CDC (centers for disease control) bacteria & viruses cause most common food poisonings.
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Minimizing the risk of Food Poisoning
Most cases of food poisoning takes place in the home. (Kitchen surfaces, serving dishes, & eating utensils)
To help keep food safe to eat, follow 4 steps:
Clean, Separate, Cook, Chill.
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4 Steps to keeping food safe
Clean: Always wash hands througlh before preparing or
handling food. Also, wash fruits & vegetables before
eating them.
Separate: Always separate raw meat, seafood, &
poultry from other items in your shopping cart, or
counter top.
Cook: Use a thermometer to make sure foods are fully cooked. Proper heat will kill
harmful bacteria.
Chill: Cold foods should be kept at below 40 degrees,
and frozen foods at or below 0 degrees.
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Maintaining a Healthy Weight
Lesson 1
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Body ImageWhen you look at yourself in
the mirror are you happy with what you see?
The way you see your body is called body image.
Body image is influenced by many factors, including media
images, friends, & family.
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Body Mass IndexBody Mass
Index: Allow you to assess your body size in relation to your height &
weight.
This is a general
measurement, and not
accurate for all body types
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Maintaining a Healthy WeightLesson 1
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Healthy Ways to Manage Weight
Know what your appropriate weight should be
Set realistic goals
Put your plan in writing
Evaluate your progress
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Healthy weight-loss strategies
Eat foods in moderation. Eat all the foods you love, just in smaller portions and not so often.
Eat a variety of foods
Drink plenty of water
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Fad Diets & Eating DisordersA number of weight-loss strategies
not only fail to produce long term results but also can cause serious health problems.
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Fad DietsLiquid Diet: A person replaces all of their food intake with a special liquid formula. (Many liquid diets do not provide the body with the fiber, calories &
nutrients it needs)
Diet Pills: Many diet pills suppress appetite. They may cause drowsiness, anxiety, a racing heart, or other serous
side effects.
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Weight CyclingSome diet plans may seem to help
you lose weight quickly, but the weight loss is usually from water, not body fat.
Weight Cycling: The repeated pattern of loss & regain of body weight.
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Eating Disorders
Sometimes a person’s concerns about their weight can get out of control. Becoming obsessed with thinness can lead to an eating disorder.
Eating disorder: An extreme, harmful eating behavior that can cause serious illness or even death.
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Anorexia NervosaAnorexia Nervosa: Disorder in which the fear of becoming obese results in severe weight loss from self-imposed starvation.
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Bulimia NervosaBulimia Nervosa: Disorder in which some form of purging or clearing of the digestive tract follows cycles of overeating.
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Binge EatingBinge Eating:
Disorder characterized by consuming large amounts of food
at one time.
Is this Moderation?
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Nutrition for Individual Needs
Lesson 2
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VegetarianismVegetarian
: Person who eats mostly or only plant
foods.
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Dietary Supplements
Dietary Supplement: A non-food form of one or more nutrients.
Dietary supplements are fine to take, however eating a healthy variety of foods will supply you with all the nutrients your body needs.
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Nutrition During Pregnancy
A developing fetus depends on its
mother for all its needs, so it’s important for
pregnant women to eat healthy & avoid harmful substances.
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FolateFolate: Helps
prevent spinal
defects in the fetus.
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Iron: Iron helps build & renew hemoglobin (the oxygen carrying compound in blood cells.
Iron
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Calcium: Helps build bones & teeth of the developing fetus & replaces any calcium taken from the mother’s bone.
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Digestion At its simplest, the digestive system it is a tube running from mouth to
anus. This tube is like an assembly line, or more properly, a disassembly line. Its chief goal is to break down huge macromolecules (proteins, fats and starch), which cannot be absorbed intact, into smaller molecules (amino acids, fatty acids and glucose) that can be absorbed across the wall of the tube, and into the circulatory system for dissemination around your body.
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Digestive Processes In many ways, the digestive system
can be thought of as a well-run factory in which a large number of complex tasks are performed. The three fundamental processes that take place are:
Secretion: Delivery of enzymes, mucus, ions and the like into the lumen, and hormones into blood.
Absorption: Transport of water, ions and nutrients from the lumen, across the epithelium and into blood.
Motility: Contractions of smooth muscle in the wall of the tube that crush, mix and propel its contents.