Nutrition is the study of nutrients in food, how the body uses them, and the relationship between diet, health, and disease. Nutritionists use ideas from molecular biology, biochemistry, and genetics to understand how nutrients affect the human body.

1. NUTRITION
PREPARED BY;
MISS RABIA KHAN BABER

2. TOPICS DISCUSSED IN PPT
What is nutrition
Classes of nutrients
What is calorie
Caloric requirement of human body
Balanced diet

3. NUTRITION
Nutrition is the study of nutrients in food, how the body uses them,
and the relationship between diet, health, and disease.
Nutritionists use ideas from molecular biology, biochemistry, and
genetics to understand how nutrients affect the human body.
Nutrition also focuses on how people can use dietary choices to
reduce the risk of disease, what happens if a person has too much or
too little of a nutrient, and how allergies work.
Nutrients provide nourishment. Proteins, carbohydrates, fat, vitamins,
minerals, fiber, and water are all nutrients. If people do not have the
right balance of nutrients in their diet, their risk of developing certain
health conditions increases.

4. CLASSES OF NUTRIENTS
There are two major
classes of nutrients
which include
Macronutrients
*Carbohydrates
*Fats
*Proteins
Micronutrients
*Vitamins
*Minerals

5. TYPES OF CALORIE
There are two types of calorie:
A small calorie (cal) is the amount of energy required to raise the
temperature of 1 gram (g) of water by 1º
A large calorie (kcal) is the amount of energy required to raise 1
kilogram of water by 1º C. It is also known as a kilocalorie.

6. CALORIES AND HEALTH
The human body needs calories to survive. Without energy, the cells in
the body would die, the heart and lungs would stop, and the organs
would not be able to carry out the basic processes needed for living.
People absorb this energy from food and drink.
If people consumed only the number of calories needed every day, they
would probably have healthy lives. Calorie consumption that is too low
or too high will eventually lead to health problems.

7. CALORIE REQUIREMENT ACCORDING TO
AGE, GENDER AND PHYSICALACTIVITY
The United States government
states that the average man needs
2,700 kcal per day and the average
woman needs 2,200 kcal per day.

8. IMPORTANCE OF
NUTRIENTS

9. NUTRIENTS
Macronutrients are required by the body in relatively large amounts;
micronutrients are needed in minute amounts.
Lack of nutrients can result in undernutrition, which can lead to
deficiency syndromes

10. MACRONUTRIENTS
Macronutrients constitute the bulk of the diet and supply energy and
many essential nutrients. Carbohydrates, proteins (including essential
amino acids), fats and water are macronutrients. Carbohydrates, fats,
and proteins are interchangeable as sources of energy; fats yield 9
kcal/g, proteins and carbohydrates yield 4 kcal/g.

11. CARBOHYDRATES
Dietary carbohydrates are broken down into glucose and other
monosaccharides. Carbohydrates increase blood glucose levels,
supplying energy.
Simple carbohydrates are composed of small molecules, generally
monosaccharides or disaccharides, which increase blood glucose
levels rapidly.
Complex carbohydrates are composed of larger molecules, which are
broken down into monosaccharides. Complex carbohydrates increase
blood glucose levels more slowly but for a longer time.

13. PROTEINS
Dietary proteins are broken down into peptides and amino acids.
Proteins are required for tissue maintenance, replacement, function,
and growth. However, if the body is not getting enough calories from
dietary sources or tissue stores, protein may be used for energy.
As the body uses dietary protein for tissue production, there is a net
gain of protein. During catabolic states (eg, starvation, infections,
burns), more protein may be used than is absorbed, resulting in a net
loss of protein.
Of the 20 amino acids, 9 are essential amino acids (EAAs), they
cannot be synthesized and must be obtained from the diet.

14. FATS
Fats are broken down into fatty acids and glycerol. Fats are required
for tissue growth and hormone production.
Basic structure of cell membrane
Build cell membranes
Carry fat soluble vitamins

15. DAILY PERCENTAGE OF
MACRONUTRIENTS
FATS
10-15%
PROTEINS
20-30%
CARBOHYDRATES
50-60%

16. FIBER
Fiber occurs in various forms (eg, cellulose, hemicellulose, pectin,
gums). It increases gastrointestinal motility, prevents constipation. Fiber
is thought to accelerate the elimination of cancer-causing substances
produced by bacteria in the large intestine

17. MICRONUTRIENTS
Vitamins and minerals required in minute amounts (trace minerals) are
micronutrients.

18. WATER
Water is considered a macronutrient because it is required in amounts of
1 mL/kcal (0.24 mL/kJ) of energy expended, or about 2500 mL/day.
Needs vary with fever, physical activity, and changes in climate and
humidity.

19. OTHER DIETARY SUBSTANCES
The daily human diet typically contains as many as 1000 chemicals. Of
these, only 300 are nutrients, only some of which are essential.
However, many non nutrients in foods are useful. For example, food
additives (eg, preservatives, emulsifiers, antioxidants, stabilizers)
improve the production and stability of foods. Trace components (eg,
spices, flavors, odors, colors, phytochemicals, many other natural
products) improve appearance and taste.

20. NUTRIENTS AND THEIR QUANTITY/DAY
NUTRIENT QUANTITY PER DAY
Energy 8,700 kilojoules
Protein 50 grams
Fat 70 grams
Carbohydrates 310 grams
Sodium (salt) 2.3 grams
Dietary Fiber 30 grams

21. BALANCED DIET

22. BALANCED DIET
A balanced diet includes foods from four groups and fulfills
all of a person’s nutritional needs. Eating a balanced diet helps
people maintain good health and reduce their risk of disease

23. WHY DO WE NEED A BALANCED DIET
A balanced diet is one that fulfills all of a person’s nutritional needs.
Humans need a certain amount of calories and nutrients to stay healthy.
A balanced diet provides all the nutrients a person requires, without
going over the recommended daily calorie intake.
By eating a balanced diet, people can get the nutrients and calories
they need and avoid eating junk food, or food without nutritional
value.

24. BASIC 4 FOOD GROUPS
A healthful, balanced diet includes foods from these four groups:
1. Green leafy vegetables and fruits group
2. Cereal group ; Bread, rice, wheat, barley
3. Meat group ; Meat, fish, egg, pulses, nuts, etc
4. Milk group ; All dairy products

25. HOW TO PLAN A BALANCED DIET
1. Age, sex and caloric requirement
2. Selection of nutrients from basic food groups
3. Economic status from Basic Food Groups
4. High-cost and low-cost diet

27. NUTRIENTS AND THEIR FUNCTION