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By the end of this session you’ll be able to :
 Define nutrition, nutrition science
 Recognize the relation between nutrition & health.
 Understand the types of Classification of nutrients
 deal with the Food Guide Pyramid
Nutrition: the process by which a living organism assimilates food and
uses it for growth and maintenance of tissues Nutrients- components of
food:
 Provide energy
 Provide structural materials
 Provide regulatory agents that support cell growth,
maintenance, and repair of tissues
 May reduce the risk of certain diseases
Nutrition science: the science of food, the nutrients and the substances
there in, their action, interaction, and balance in relation to health and
disease, and the process by which the organism ingests, absorbs, transport,
utilizes, and excretes food substances”---- The Council on Food and
Nutrition of the American Medical Association
Actions in the body include:
 Ingestion
 Digestion
 Absorption
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 Transport
 Metabolism
 Excretion
Nutritional Goals:
 Quality intake: that allows you to function at your best and promotes
health. Intake that provides adequate levels of each nutrient
 Quantity of intake: that promotes a healthy body weight.
Diet and Health:
Diet - the foods one consumes
 The quality of your daily diet affects the risk of chronic diseases.
Meaning…..The food choices you make daily have a cumulative
impact on your health
 Nutrition plays a central role in all life functions
 Animals often spend a large amount of time and energy obtaining
food and feeding, but we humans do not
 Nowadays we can choose between nutritious/non-nutritious
foods
 Food choice makes a big difference to our health and the risk of:
deficiency – under nutrition ,excess – over nutrition
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 Our food choices are determined by:
- habits usually established in childhood
- personal likes and dislikes
- cost of food
- convenience of shopping and preparing
- education about what is nutritious and healthy
Chronic health issues associated with diet include:
 Cardiovascular disease
 Hypertension
 Obesity
 Type II Diabetes
 Osteoporosis
What’s Considered Food?
 Foods contain nutrients and are derived from plant or animal
sources
 Nutrients are used by the body to provide energy and to support
growth, maintenance and repair of body tissues
~ 40 nutrients identified at this time
Classifying Nutrients
I) (according to its types) There are 6 Classes of Nutrients:
1. Carbohydrates
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2. Lipids (fats)
3. Proteins
4. Vitamins
5. Minerals
6. Water
Body composition
II)
Essential or nonessential
Essential nutrients : nutrients the body either cannot make or cannot
make enough of to meet its needs. These nutrients must be obtained from
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foods (ingested in some manner Examples: Vitamins, Calcium, iron, and
other minerals, some of the amino acids.
The Six Criteria for Nutrient Essentiality:
The nutrient….
 is essential for one or more of the (8) functions of life
 is not synthesized or synthesized adequately in the body
 has a function that is either biochemical or structural
 if deficient, a recognizable loss of function or structure results
 if deficient the loss of function or structure is proportional to
degree and duration of depletion
 if deficient the loss of function is, in the short term, reversible by
the specific nutrient
Essential Nutrients and Life Functions:
Life Functions
Key Essential Nutrients
Movement
Calcium
and
vitamin
D
–
bones,
Protein and potassium - muscles
Respiration
Vitamin B – metabolism, iron – oxygen
transport,
Iodine – thyroid hormone and metabolic rate
Sensitivity
B vitamins - central and peripheral nerves
Iron and iodine - intellectual development
Nutrition
Zinc and iron - appetite
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Excretion
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Water, sodium and potassium - urine excretion
Reproduction
Iron and B vitamins – fertility and pregnancy outcome
Growth
Energy, protein, iron, zinc, vitamin A – infant growth
Defence
Protein, vitamin A and zinc - immune function
Nonessential nutrients: body can make from other nutrients ingested
—  Examples: Cholesterol Some amino acids.
—
III)
Classifying Nutrients by Composition:
Organic nutrients -
contain carbon: Carbohydrates ,Lipids, Proteins,
Vitamins
Inorganic nutrients - do not contain carbon,: Minerals, Water
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IV) Quantity Needed:
Macronutrients: need in relatively large amounts :Carbohydrates, lipids,
proteins
Micronutrients: need in relatively small amounts :All other nutrients
V)Energy-yielding nutrients :
Carbohydrates, Fats (lipids),Proteins
Food guide pyramid
In 1992, the USDA (United States Department of Agriculture) adopted
the nutritional guide that was created at Tufts University. It is in the shape
of a pyramid, to help people remember what food to eat. The pyramid
looks like this:
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This pyramid shows different food groups, and the servings you should
have of each. For example, you should have 6 to 11 servings a day of foods
in the Bread, Cereal, Rice & Pasta Group. We notice that the bottom of the
pyramid, the biggest part, is the Bread, Cereal, Rice & Pasta Group. This
pyramid shows that that is where you should get the most servings per day.
The top part, the Fats, Oils & Sweets Group is the smallest. That shows that
you shouldn't have too much fat or oil in your diet.
In April 2005, the USDA replaced the original pyramid with another
pyramid by turning it on its side and making the sections vertical instead of
horizontal. Looking at this pyramid, there are different colored parts of the
pyramid, but each one gets smaller as it goes toward the top. The part
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toward the top is for the less healthy foods in the category, and the part at
the bottom is for the healthier foods..
For example, you might put whole milk at the top of the Milk group, and
non-fat milk at the bottom; or you could put whole grains at the bottom of
the Grains group and refined grains at the top. The parts of the pyramid
also show how important they are by the width of the band. The small
yellow one that has no name on the bottom contains fats and oils. The
unsaturated oils, like peanut, canola, or olive, would be at the bottom.
Butter would be at the top. The person climbing the steps on the left side of
the pyramid symbolizes the importance of exercise.
Faculty members at the Harvard School of Public Health made an
alternate pyramid, which they called the Healthy Eating Pyramid.
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Notice this pyramid has a section on the bottom called Daily Exercise
and Weight Control. It is built this way to show that daily exercise and
weight control are the foundation for good health.
Faculty members at the Harvard School of Public Health made an
alternate pyramid, which they called the Healthy Eating Pyramid.Notice
this pyramid has a section on the bottom called Daily Exercise and
Weight Control. It is built this way to show that daily exercise and weight
control are the foundation for good health. The nutrition advice in the
Dietary Guidelines for Americans is changed every five years.
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