1. 1 2 Food components and their significance
in the body (Very Basic Nutrition). 1 2

2. 1

3. 2

4. Facilitated diffusion: water soluble vitamins utilize carrier to
Digestion, Absorption, Transport
a) Digestion: via enzymes action, responsible for digestion or breakdown of food molecules into absorbable units or pieces.
b) Absorption:
Occurs when digested nutrients enter bloodstream through the capillaries of the small intestine. Nutrients must pass through absorptive (mucosal) cells of the digestive system, in one of three ways:
Simple diffusion: small lipids and water.
Facilitated diffusion: water soluble vitamins utilize carrier to
Transport them into mucosal cells
Active transport: glucose and amino acids are absorbed with
The cost of energy input

5. c) Transport
The vascular (blood or circulatory) system delivers nutrients
And oxygen to all of the body’s cells
(more complex than this). Go to:
(not free)

6. Free
Once absorbed from the small intestine, all nutrients require transport to cells in need of their support. Additionally, molecules manufactured in other cells sometimes require delivery to other organ systems. Blood is the conduit and blood vessels are the highway that support nutrient and molecule transport to all cells.
Water-soluble molecules, such as some vitamins, minerals, sugars, and many proteins, move independently in blood.
Fat-soluble vitamins, triglycerides, cholesterol, and other lipids are packaged into lipoproteins that allow for transport in the watery milieu of blood.

7. What is “Food” and what is “Nutrition”?
Food : any edible material that supports growth, repair and maintenance of the body.
Food also protects the body from infections and diseases.
Nutrition : the process by which body utilizes food for growth and maintenance and healthy living.
Food “functions” in the body through the nutrients it contains.
Functional food?

8. What are nutrients?
Nutrients : substances found in food. These are: Carbohydrate, Fat/Oil, Protein, Vitamins & Minerals ·  Since Water is indispensable for life, it is considered both as a food and as a nutrient.
Dietary Fibre and some Phytochemicals of plant foods, although not nutrients as such, are needed for good health.
HOT questions:
Bacteria: are they nutrients? Enzymes; are they nutrients?

9. HOT

10. What food does in the body does through the nutrients it contains (you are what you eat?)
The body utilizes these nutrients to grow and keep healthy and strong. All nutrients needed by the body are available through food.
No food by itself (except for breastmilk which is adequate for babies up to six months of age) has all the nutrients needed for full growth and health. Food therefore must be balanced.
We therefore need a variety of foods to get all the nutrients the body needs.

11. Each nutrient has its own function/role in the body.
Specific nutrients do their best work in the body when present with other nutrients.
Nutrients are therefore mutually supportive.
e.g.

12. Macronutrients and Micronutrients
The nutrients can be divided into two major groups – “Macronutrients” and “Micronutrients”.  
Macronutrients are those that are needed in large quantities (tens or hundreds of grams) every day. These are: Carbohydrates, protein and fats/oils.  
Micronutrients are those that are needed in minute quantities (micrograms or at best milligrams). These are vitamins, minerals and trace elements.

13. Carbohydrates
Main function is energy production in the body.   Largest source of energy: percent of the total energy intake in different countries. Neither extreme is good. The ideal contribution is ~ 60 percent.  
One gram of carbohydrate provides 4 Kcal.   Grains (rice, wheat, maize), roots and tubers (potato, sweet potato, guam, banana) and legumes (pulses, nuts) are rich sources of carbohydrates.
See Nutritional overview of CHO:

14. Nuritional overview of carbohydrate

15. Carbohydrates are present in two forms:  
a) Simple carbohydrates: glucose, fructose, sugar (sucrose)
b) Compound carbohydrates: starch in plants and glycogen in animals (liver and muscles) Compound carbohydrates are polymers of glucose.
Done this!

16. Digestion,
absorption

17. During well-fed conditions, body glucose is stored in liver and muscles as glycogen, a compound carbohydrate.
Glycogen is therefore the animal counterpart of plant starch.   During starvation (or fasting), glycogen of liver and muscle is broken into glucose to provide energy.  
Glucose is the only metabolic fuel for the brain under normal conditions.   Carbohydrates taken in excess of energy requirements are directly converted into fat and deposited in the body.

18. Protein  
Protein : the building material for all body parts, such as muscle, brain, blood, skin, hair, nails, bones and body fluids. It is essential for growth, repair of worn-out tissues, replacement of used-up blood and resistance against infections.  
Protein comes from both animal and plant foods. Meat, fish, egg, and milk and milk products are rich sources of animal protein.   Pulses, nuts and beans are rich sources of plant protein.  
Cereals are low in protein (e.g. rice: 6 – 8%, wheat: 12 – 14%), but because of their large quantities in the diet, they meet a major portion of total dietary protein requirement.

19. Animal proteins are of high quality (“first-class” proteins) because of their more complete and balanced composition of amino acids.  
Plant proteins are of lower quality (“second-class” proteins) because they are incomplete in one or more of the essential amino acids.  
Combination of two or more plant foods can mutually supplement each other’s deficiency and therefore give rise to high quality protein.

20. The protein from beans and legumes are of better quality than the protein from rice and wheat products. These foods are considered less expensive meat substitutes and are often called the ‘poor man’s meat’.  
Potato is poor in protein (<3%), but this protein is of high quality!

21. Amino acids, which can be manufactured in the body are called “non-essential”, while others must be provided pre-formed by food are the essential amino acids.

22. Small intestine,
Pancreas, liver,
gallbladder
Large intestine
(colon)
Stomach
Mouth

23. Which is harder to digest?
Why?
So what?

24. Although the main function of protein is to build and maintain the body, it also gives energy. One gram of protein gives 4 Kcal.
(this is a definitely wrong representation ! Why I did this?)

25. Fats
A triglyceride may be a FAT or OIL, depending on the predominant type of fatty acids it contains: saturated, monounsaturated and polyunsaturated.
When predominant fatty acids are saturated and monounsaturated, then it is solid at room temperature and is termed as FAT.

26. Fats/Oils Fats/oils are concentrated sources of energy needed by the body.
The term “fat” is commonly used to refer to a family of compounds called “lipids” which are water-insoluble.
They include triglycerides, phospholipids and sterols such as cholesterol.
Triglycerides predominate both in the food and in the body. 1 gram of fat provides 9 kcal, i.e. more than double the energy given by carbohydrate or protein per unit weight.

27. Usually, triglycerides of land animal sources are FATs
Usually, triglycerides of land animal sources are FATs. Examples are fats of beef, mutton, goat and chicken skin.
Saturated fatty acids are cholesterologenic, i.e. they increase blood cholesterol level.
Aquatic animals like the fish, especially the marine fish, have good preponderance of polyunsaturated fatty acids and their fat is actually OIL.

28. Oils
When polyunsaturated fatty acids predominate, then it is liquid at room temperature and is termed as OIL.
Usually, triglycerides of plant sources are OILs. Examples are vegetable oils - mustard oil, soybean oil, sunflower oil, corn oil and other cooking oils.
However, coconut and palm oil contain large proportions of saturated and monounsaturated fatty acids.
Omega 3 fatty acids: see video shared by your friends!

29. Small intestine,
Pancreas, liver,
gallbladder
Large intestine
(colon)
Stomach
Mouth

30. Fat provides the building materials for some body parts, such as brain, nerves and hormones.
It also facilitates absorption, transport and storage of fat-soluble vitamins A, D, E and K. Fat is therefore an essential nutrient.
Like all other nutrients, fat is beneficial if consumed in the right amount and if it is the right type.

31. Nutrition and health