Chapter 5 Nutrition and Your Health. Why Do you Eat? Nutrients- substances in food that your body...

Chapter 5

Nutrition and Your Health

Why Do you Eat?

Nutrients- substances in food that your body needs to function properly to grow, to repair itself, and to supply you with energy.

Hunger- is a natural drive that protects you from starvation.

Appetite is a desire, rather than a need, to eat.

Nutrition- is the process by which the body takes in and uses food.

Shaping your Appetite

Your environment: Your food choices reflect the culture you live in, ethnic

background and religious beliefs. Your family and friends greatly influence the choices that

you make regarding food decisions and preferences. Food ads are everywhere in the media. Advertising is created to make you aware of certain foods

and, perhaps, to sell you on their benefits. Cost, convenience, and food safety can be a huge

determining factor in food choices. All relating to time and money.

Shaping your Appetite

Your emotions: Emotions are another factor that affects eating

habits. Eating when bored Feeling stressed, frustrated, or depressed Not eating when you are upset or bored

Vitamins Vitamins- are compounds that help regulate many vital body

processes, including digestion, absorption, and metabolism of the other nutrients.

Of the 13 vitamins that play a key role in good nutrition, only 1; Vitamin D is produced in the body.

Others are derived from food Water- Soluble

Water soluble vitamins dissolve in water and thus pass easily into the bloodstream.

Excreted through urine Not stored in body, so you must replenish frequently.

Fat-Soluble Absorbed and transported by fat Stored in fatty tissue, liver and kidneys Excess build up can be damaging

Minerals

Minerals- inorganic substances that the body cannot manufacture but that act as catalysts, regulating many vital body processes.

Body requires different amount of various minerals

Trace minerals- tiny amounts

Water

Water- carries nutrients and carries waste away from cells, mainly through plasma.

Lubricates your joints Cools the body Body uses 10 cups or 2.4L of water per day DRINK 6-8 glasses per day

Carbohydrates

The starches and sugars found in food Body’s preferred source of energy Recommended intake is between 45-65%

total caloric energy Simple carbohydrates– or sugars Complex carbohydrates– or starches

Carbohydrates

Simple Carbohydrates Naturally present in food Burned quickly in body,

not a good source of energy

Fruit- fructose Milk- lactose Grains- maltose Sugar- sucrose

Complex Carbohydrates Rice, grains, seeds, nuts,

and legumes Second in energy source 4 calories of energy/

gram of carbohydrate Body converts to glucose

Carbohydrates

Glucose- simple sugar and chief fuel of the body.

If glucose is not used as energy right away, it is stored as glycogen.

Glycogen- starch-like substance that converts back to glucose when needed.

Can be stored as fat if consumed and not used by the body.

Fiber

Most Americans need to increase their fiber intake. Recommended 14 grams/1000 calories Form of a carbohydrate Fruits and vegetables with edible skins and seeds,

whole-grain foods Helps with digestion, feeling of fullness, lower in fat

and calories, reduces the risk of cancer and heart disease, and lowers blood cholesterol.

Protein

Nutrients that help build and maintain body tissues.

All body cells contain proteins. Excess protein is stored as fat. Final source of energy for the body. Protein is made from amino acids

Body can make 11 of the 20 amino acids needed to make protein; 9 must come from food and are known as essential amino acids

Roles of Protein

Builds new body tissues Replaces damaged or worn out body tissuses Aids in the production of enzymes,

hormones, and antibodies.

Fats

Body needs some fat to function healthfully Most concentrated form of energy Intake of saturated fats should be decreased Trans fats should be 1% of energy intake Omega-3 fatty acids are important—eat 2

servings of fish weekly Total fat intake should be 25-35% of calorie

intake.

Fats

Saturated fats Found in animal products

and some oils Can lead to an increased

risk of heart disease

Unsaturated fats Found in vegetable oils,

olive oil, corn oil, etc. Can reduce the risk of

heart disease Hydrogenation- can

make products more saturated

Role of Fats in the Body

Fats carry fat-soluble vitamins to the blood (A, D, E, K)

Teenage girls should limit their fat intake to 66 grams a day and cut their fat intake to no more then 30% of the daily caloric intake.

Cholesterol

Fatlike substance produced in the liver of animals and only found in foods of animal origin.

Production of sex hormones Production of Vitamin D Is a major risk factor for circulatory diseases

Energy Used in the Body

Simple sugar carbohydrates Complex carbohydrates Fat Protein

What you should be eating?

Choose plenty of grains, veggies, and fruits

Excellent source of complex carbohydrates Source of fiber Low in fats and calories Decrease risk of heart disease, obesity, and

cancers Recommend 20-35 grams


Choose an Eating Style Low in Fat, Saturated Fat, and Cholesterol

Makes up about 35% of calories in an average diet

Increase risk of increased cholesterol and heart disease

Limit egg yolks, organ meats like liver


Choose an Eating Style Moderate in Sugars

Watch the size and frequency of foods with added sugars

Be aware of added sugar Learn to identify added sugars by name Water, not syrup Eat sweets as a part of a meal, not as in

between snacks

What you should be eating? Choose an Eating Style Moderate in Salt and

Sodium One of the body’s essential minerals Transports nutrients to and from cell 2, 400mg or less sodium a day 10% naturally present in foods; 75% from processed

foods Risk of high blood pressure Become sodium literate Season food with spices other then salt Taste before you salt

Reading a nutrition label Nutrition labels indicate the nutrients and calorie content of foods Find good sources Compare Choose Label Contains:

Serving size Servings per container Calories per serving and calories per serving of fat Grams of total fat, sat. fat, total carbs, fiber, sugar, protein, and

mg of cholesterol and sodium per serving % of Daily Value (DV) the product supplies of the above nutrients

Nutrition Label

Reading a food label

Reading a nutrition label

Ingredients are listed by weight in descending order Food Additives- substances added to food

intentionally to produce a desired effect. Add nutrients lengthen storage life Give flavor and color Maintain texture Help in the aging process i.e cheese

Enriched foods- food in which nutrients were lost in processing and have been added back

Fortification- the addition of nutrients that were not naturally present

Food Label Claims

Healthy- low in fat and saturated fat; limited amounts of cholesterol and sodium

Light- calories reduced by at least 1/3 or fat or sodium by ½

Less- contains 25% less of a nutrient or calories than another comparable product

Free- contains no amount of small amount fat, cholesterol, sodium, etc.

Fresh- raw, unprocessed, no preservatives, never frozen or heated

Natural- meat and poultry

Product Dating

Expiration Date- last date to use the product Freshness Date- last date food thought to be

fresh Pack Date- date in which the product was

packaged Sell Date- also known as the pull date; when

the last day the product should be sold

Dietary guidelines and Food Pyramid

RDA- Recommended Dietary Allowances. This is the amount of nutrients that will prevent deficiencies and excesses in most healthy people.

Specific nutritional needs for different people Age Gender Physical condition Body size Activity level


Balance the amount of energy in food with the amount of energy your body uses.

Be aware that controlling body fat is more important to health than controlling body weight.

The New Food Pyramid

www.choosemyplate.gov

Digestive System

Digestion- the mechanical and chemical breakdown of foods for use of the body’s cells.

Absorption- the passage of digested food from the digestive tract to the circulatory system.

Elimination- the expulsion of undigested food or body waste.

Structures of the Digestive System

Oral Cavity: The mouth and teeth

Mastication- the process of chewing The salivary glands Produces saliva that aids in the secretion of

enzymes to start the digestion of carbohydrates. The tongue

Aids in the process of swallowing; forcing the food into the pharynx

Uvula protects the nasal passages Epiglottis protects the trachea or windpipe


The Esophagus Extends from the pharynx to the stomach Peristalsis- a series of involuntary muscle contractions Sphincter muscle prior to stomach

The Stomach Hollow organ contained within 3 muscle wall Breaks down food Acts as storage Controls rate at which food enters the small intestine


The Small Intestine Major part of digestion

and absorption occur here

Can be up to 20 feet long!

Has 3 parts; duodenum, jejunum, and ileum

The Large Intestine Can be 5 feet long! Movement is slow Absorb water and

eliminate undigested food


The Liver The second largest organ in body Body’s chemical factory Excretes bile; important in the breakdown of fat

The Gallbladder Located under liver Pear- shaped organ Stores bile

The Pancreas Produces hormone insulin

Food Sensitivity An allergy is the body’s reaction to an irritating substance or

toxin. An allergic reaction can be caused by an insect bite, or from food.

Food allergy- the body’s immune system overreacts to substances in some foods The allergens are usually proteins The body produces antibodies as a defense against these

substances Most common allergies: nuts, eggs, wheat, and soy Food additives that help in preserving foods

Symptoms include: rash, hives, or itching of the skin, vomiting, diarrhea, or abdominal pain

Food Intolerance- is a negative reaction to food or an ingredient in food that is not related to the body’s immune system or food poisoning.

Protecting yourself from food-borne illness Food borne Illnesses- food poisoning is often a

result of a contaminant Bacteria Parasite Virus

Cannot see, smell or taste Causes and Symptoms of Food borne Illnesses

Animals can harbor disease organisms in their tissues. Pasteurized- treated by a process of heating to destroy or

slow the growth of pathogens. Food may be contaminated with bacteria spread from a

person or animal.

Food-Borne Illness Salmonella

There are 2000 different species of salmonella 5 million cases in the United States occur every year Most common food borne illness Rate of infection highest in babies and young children Incubation period varies between 12-36 hours

Transmission: Ingestion of food or water contaminated by the organism

Common foods include: Inadequately cooked poultry, raw sausage, lightly cooked foods containing egg or egg product, unpasteurized milk or dairy.

Symptoms: sudden onset headache, abdominal pain, nausea, and sometimes vomiting

Food-borne Illness

Staphylococcus Aureus (S. Aureus)

Food Intoxication Short incubation 2-4 hours Short duration Rarely fatal Transmission: Ingestion of

food containing toxin Symptoms: abrupt, violent

onset, nausea, vomiting, diarrhea

Clostridium Perfringens (C. Perfringens)

Food Intoxication Mild, short duration Incubation 6-24 hours Transmission: Ingestion of

food containing organism Symptoms: mild cramps,

diarrhea

Food-borne Illness

Escherichia Coli (E. Coli) Transmission: Ingestion of

food or water contaminated with the organism

Symptoms: diarrhea; stools may contain blood or pus

Clostridium Botulinum (Botulism)

Life- threatening illness; affects nervous system; incubation 12-36 hours

Transmission: ingestion of food containing toxin

Symptoms: dizziness, difficulty swallowing, double vision, nausea, vomiting, diarrhea, descending paralysis