S IX N UTRIENTS LGHS Nutrition and Food Science Unit 1: Food for Life Revised August 2015.
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Transcript of S IX N UTRIENTS LGHS Nutrition and Food Science Unit 1: Food for Life Revised August 2015.
WORDS TO KNOW!NUTRITION - is the science that
studies how body makes use of food.
DIET - is everything you eat and drink.
NUTRIENTS - are the substances in food.
ESSENTIAL NUTRIENT
a nutrient required for normal body functioning that either cannot be synthesized by the body at all, or cannot be synthesized in amounts adequate for good health (e.g. niacin, choline), and thus must be obtained from a dietary source
THE PROCESS OF SATISFYING HUNGER
1. You need energy2. You feel hungry3. You eat to get rid of hunger4. You feel satisfied5. You need more energy6. The cycle repeats again
WHAT FOOD DOES FOR YOU?It provides energy for daily activity
It gives you raw material
Eating is an enjoyable activity
CARBOHYDRATESCarbohydrates are the primary source of energy.
Sources of Carbohydrates: - Whole wheat breads - Rice - Pasta - Potatoes
TYPES OF CARBOHYDRATES Simple Carbohydrates - Glucose,
fructose, dextrose and sucrose are carbohydrates in their simplest form, sugars.
Found naturally in fruits, milk and vegetable like peas.
Refined sugars that come from sugar beets and sugarcane are used in processed foods, sweeteners and as table sugar.
TYPES OF CARBOHYDRATES CONT. Starches – more complex
carbohydrates
Found in rice, potatoes, vegetables, breads and cereals.
Essential to your health and very important in your diet because they provide needed nutrients.
TYPES OF CARBOHYDRATES CONT. Fiber – complex carbohydrates that form the
tough cell walls in plant cells. Humans can’t digest fiber but it’s important
to our diet because it helps keep food moving through the digestive tract.
Helps the intestines in good working order. Found in…
All plants supply some fiber Whole grains Fruit Vegetables
GLYCOGEN Glycogen is what the one pound of
carbohydrates that is stored in the liver is called.
Used when the body needs quick energy.
All other excess carbohydrates are converted to fat and stored as fatty tissue.
PROTEINo Protein is essential for body growth and
repair of body cells.
o Every tissue is made of some form of protein.
o Enzymes, antibodies and hormones are all proteins.
o Without a regular supply of new protein we couldn’t grow new cells, our wounds wouldn’t heal and our worn-out cell wouldn’t be replaced.
PROTEIN CONT. o If the body doesn’t get enough calories
from carbohydrates and fats then protein can be used for an energy source.
o Excess protein is changed to fat and stored in the body.
Sources of Protein:- Meat, Eggs, Fish, Nuts, Beans, Poultry,
Dairy Products and some grains, nuts, seeds, and legumes.
FATSo Fats are the nutrient that supplies the
MOST energy. More than twice as much as carbohydrates.
o They carry four important vitamins A,
D, E and K. o They supply some fatty acids that are
absolutely necessary for good health.
FATSo Fat stored in body helps to insulate,
cushion and protect us.
Sources of Fat: Butter, Oils, Salad Dressings, Cheese, Eggs, Meat, Whole Milk, Ice cream, Poultry, Fish, Nuts, seeds, Avocados, Olives, sauces, bakery foods, fried foods and even some candies contain fat.
VITAMINSo Vitamins help regulate body functions.
o 1913 vitamins were discovered and the following were identified as the major vitamins.
o A, B (8 different B vitamins), C, D, D
and K. others such as niacin don’t have names.
VITAMINS Vitamins are in foods in small amounts
but without the small amounts our cells couldn’t do their jobs.
Vitamins help to form material that holds cells together, for helping bones and teeth to use calcium, for helping the body use energy, and for many other critical life-support activities.
MINERALSo Minerals are very diverse and have tasks like
building strong bones or maintaining the right amount water in cells.
o Major Minerals Needed: Calcium, magnesium, phosphorous, sodium, chlorine and potassium.
o Other minerals are needed in small amounts
they are called trace mineralso Iron, iodine, fluoride and zinc
WATERo Most important nutrient.
o Carries nutrients to cells and takes waste away.
o Makes up two-thirds of the body.
o It is part of every cell.
WATERo Helps to regulate the bodies
temperature.
o Every food has some water in it.
o Humans can live several weeks without food but only a few days without water.
MACRONUTRIENTSnutrients that provide calories or energy. Macro means big so these are nutrients needed in large amounts. Three macronutrients required by humans:
Carbohydrates (sugar) lipids (fats) Proteins
Macronutrients provides energy in the form of calories.
MICRONUTRIENTSDietary components(vitamins and minerals) only required by the body in small amounts. Vital to development, disease prevention, and wellbeing.
Micronutrients are not produced in the body and must be come from the diet
BIOAVAILABILITY
The proportion of a nutrient that is absorbed from the diet and used for normal body functions.
Bioavailability of macronutrients is usually very high, more than 90%. (Carbohydrates, proteins and fat)
Micronutrients (vitamins, minerals and bioactive phytochemicals ((flavonoids, cartenoids) can vary widely in the extent they are absorbed.