NUTRIENTS

© Food – a fact of life 2009

NUTRIENTS


a. Macronutrients

b. Micronutrients

Extension


MacronutrientsThe macronutrients are: - Nutrients that can be used by the body as

a fuel source

• carbohydrate;

• protein;

• fat


Functions of Carbohydrate

Carbohydrates are the primary source of the body’s energy.

GLUCOSEThe most significant monosaccharide; found in nature

GLYCOGENThe storage form of glucose in the body; it is stored in the liver and muscles.


Categories:

• SIMPLE CARBOHYDRATE

S

Sugars, including monosaccharide

and disaccharides.

• COMPLEX CARBOHYDRATE

Long chains of many sugars, including

starches and fibers


-Originally called saccharides meaning _____?-Contain carbon, hydrogen, and oxygen.

-Synthesized in plants through the process of photosynthesis.

CARBOHYDRATES


Classifications of Carbohydrate

A. Monosaccharides are the simplest form of carbohydrate molecules.

1. GLUCOSE – physiologic sugar, blood sugar or dextrose sugar.

2. FRUCTOSE – levulose or fruit sugar


3. GALACTOSE – formed during the hydrolysis of lactose

B. Disaccharides - are pairs of monosaccharides linked together.

1. SUCROSE – cane sugar, beet sugar or table sugar.

2. MALTOSE – malt sugar

3. LACTOSE – milk sugar


C. POLYSACCHARIDES – complex carbohydrates stored in animal tissues which is readily converted to glucose.

COMPLEX CARBOHYDRATES


1. STARCHES – storage form of carbohydrates in plants. (hundreds to thousands)Straight form – amyloseBranched form – amylopectin

2. FIBERS – structural parts of plants, indigestible part of food.Viscous fiber/soluble fiber (oatmeal, peas, legumes)Non-viscous/ insoluble fiber(barley, celeries, broccoli)


3. CELLULOSE– composed of many glucose units.

4. HEMICELLULOSE – indigestible polysaccharide found in agar, pectin's, woody fibers, leaves and stem.


Functions of Carbohydrate:

main source and cheapest form of energy

for the body.

main source and cheapest form of energy

for the body.

Protein SparerProtein Sparer

Regulator of Fat Metabolism

Regulator of Fat Metabolism


Sole energy source for the Brain and

nerve tissues

Sole energy source for the Brain and

nerve tissues

Regulator of intestinal peristalsis

Regulator of intestinal peristalsis


Excessive consumption of carbohydrate

CARBOHYDRATE MALNUTRITION

Increased body weight

When too much carbohydrate is consumed and not used for energy over an extended period of time, it is stored as fat. Building up too much fat will increase body weight.


Increase Dental Caries/ CavitiesIt is important that teeth are brushed thrice a day and foods high in sugar should be eaten with main meals, rather than in between snacks to prevent dental caries.

PLAQUE-Deposit of bacteria, protein and polysaccharide during a period of 12 to 24 hours with the absence of brushing.


Diabetes-a disorder which the body does not metabolize carbohydrates properly.It results from inadequate and inefficient insulin.

ADHD (Attention Deficit Hyperactivity

Disorder)

- A developmental disorder of children


Lack of carbohydrate

weight loss

lethargy


HYPOGLYCEMIA-is a term used to describe an abnormally low blood glucose level.

Lactose Intolerance-is a problem for certain people who have a deficiency of the enzyme lactase.


FOOD SOURCES:

sugars

Cereal grains and products

Root crops


PROTEINS

- Protein is needed for growth, development and repair of the body.

- Proteins have the elements carbon, hydrogen,& oxygen, however, it is the nitrogen content of protein that distinguishes it from the other organic compounds.


AMINO ACIDS – building blocks of proteins

CLASSIFICATIONS OF AMINO ACIDS:

1.INDISPENSABLE AMINO ACIDS – cannot be synthesized in the body at a rate sufficient to meet growth and maintenance requirements

2. DISPENSABLE AMINO ACIDS – amino acids that can be synthesized in the body.

3. CONDITIONALLY INDISPENSABLE – amino acids that become indispensable or essential under special circumstances or conditions.


1.SIMPLE PROTEINS – yield only one amino acid upon hydrolysis.

2. COMPOUND OR CONJUGATED PROTEINS – simple proteins combined with a non- protein group.

A. ACCORDING TO CHEMICAL STRUCTURE OR PROPERTY


3. DERIVED PROTEINS – substances resulting from the decomposition of simple & conjugated proteins by the action of heat and other physical forces.

B. ACCORDING TO SHAPE OR PHYSICAL FORM

1. FIBROUS PROTEINS


2. GLOBULA

R PROTEINS

C. ACCORDING TO AMINO ACID CONTENT

1. COMPLETE PROTEINS – contains all the essential amino acids in proportions capable of maintaining life and supporting a normal growth rate

1. COMPLETE PROTEINS – contains all the essential amino acids in proportions capable of maintaining life and supporting a normal growth rate

2. PARTIALLY COMPLETE PROTEINS – can maintain life but cannot support a normal rate of growth

2. PARTIALLY COMPLETE PROTEINS – can maintain life but cannot support a normal rate of growth


3. INCOMPLETE PROTEINS – proteins that cannot support life and growth.

3. INCOMPLETE PROTEINS – proteins that cannot support life and growth.

FUNCTIONS OF PROTEINS

1. As building materials

2. As source of energy


3. Regulator of body processes


Protein deficiency

Protein deficiency is rare, but there is a condition called PEM – protein energy malnutrition. This can be seen in infants with stunted growth or thin arms and legs, and large distended abdomens.

Marasmus - this condition mainly affects infants causing them to become thin and weak. The body adapts to the shortage of energy and nutrients. All energy stores are depleted as it is used to supply vital organs.

Kwashiorkor - this condition is known to be the body’s adaption to shortage of energy and nutrients.


Kwashiorkor


Marasmus


FOOD SOURCES:

High biological value (HBV) proteins include:meat, fish, eggs, cheese, and milk.


Low biological value (LBV) proteins include:cereals, some nuts and vegetables.


The body’s needs for protein

Babies and children have a high need for proteinbecause they are growing.

Adolescents need protein for their rapid growth spurt.

Pregnant women need more protein than other adults because of the growing baby.

Nursing mothers also need more protein for lactation.


FATS

Lipids – refer to fats, oils and fat-like substances.

Fatty Acids – building blocks of lipids

Triglycerides – storage form of fat in the body.


CLASSIFICATIONS OF FATTY ACIDS:

1.SATURATED FATTY ACIDS – abundant in animal fat and plant oils like coconut oil and palm oil.

2.UNSATURATED FATTY ACIDS a. Monounsaturated fatty acid

(MUFA)

b. Polyunsaturated fatty acid (PUFA)


Sources of saturated and unsaturated fats

• Saturated fatMeat, coconut oil, palm oil, cakes and biscuits, lard.

• Unsaturated fat* Mono unsaturated fatRapeseed oil, avocado and olive oil.

* Polyunsaturated fatOily fish, sunflower oil and pine nuts.


CLASSIFICATIONS OF LIPIDS

1. SIMPLE LIPIDS - yield only fatty acids during hydrolysis

2. COMPOUND LIPIDS – fatty acids combined with CHO & nitrogenous groups.

3. DERIVED LIPIDS – formed by hydrolysis or enzymatic breakdown of simple and compound lipids


FUNCTIONS OF FATS

1. Source of energy and storage form of

energy2. Insulation and

Padding

3. Provide satiety value

4. Contribute to palatability of food

5. Spares protein


FAT MALNUTRITION

Overweightedness/ Obesity

Overweightedness/ Obesity

Heart DiseaseHeart

Disease


FOOD SOURCES

ANIMAL FATS

VEGETABLE FATS


VISIBLE FATS

INVISIBLE FATS

NUTRIENTS

Food

fact of life

food sources

proteins protein

essential amino acids

indispensable amino

complete proteins

globular proteins

fibrous proteins