THE NUTRIENTS

CARBOHYDRATES

• an organic compound that contains the

elements carbon, hydrogen and oxygen

arranged as monosaccharides or multiples of

monosaccharides

Classification of Carbohydrates:

I. Monosaccharides – has one sugar unitCarbohydrate Source

•Glucose ( grape sugar dextrose or corn sugar)

Grapes, corn, honey, fruitsdigestive end product of sugars and starches

•Fructose (fruit sugar) honey, ripe fruitsdigestive end product of sucrose

•Galactose not found free in naturedigestive end product of milk

II. Disaccharides – has 2 sugar units

Carbohydrate Source

•Sucrose ( table sugar or cane

sugar)

most common table sugar,

molasses, sugarcane, fruits

•Lactose (milk sugar) Milk and milk products

•Maltose (malt sugar) Malted products, cereal

III. Polysaccharides – more than 10 saccharide units

Carbohydrate SourceA. Digestible• Starch Cereal grains, rice, wheat, tubers

Unripe fruits and vegetables, legumes• Dextrins Toasted bread• Glycogen (animal starch) Liver, oyster, muscle meatB. Partially Digestible• Inulin Tubers, onion and garlic• Mannosans legumes

C. Indigestible• Cellulose Skins of fruits, covering of nuts and

legumes, stems and mature leaves• Hemi-cellulose a. Agar-agar seaweeds b. Pectins Slightly unripe fruits

Polysaccharides

* Dietary Fiber

– indigestible part of food

- also called roughage

- 20 to 30 grams of fiber per day is recommended

Functions of Dietary Fiber

Provides bulk

Acts as a broom in our digestive tract to prevent

constipation

Aids in normal elimination of waste

Reduces incidence of colon cancer

Reduces blood cholesterol level

Functions of Carbohydrates in the Body

• Chief source of energy – provides 4kcal/gram• Cheap and main energy food• Protein sparer• Regulator of fat metabolism• Sole energy source for the brain and nerve

tissues• Storage form of energy as glycogen• Regulator of peristalsis and provider of bulk

Food Sources of Carbohydrates:

• Sugars, fruits and milk

• Cereal grains and products ( rice, corn, oat,

breads and other baked goods, noodles or

pasta)

• Root crops, vegetables and legumes

Molasses Malted barley

CARBOHYDRATES

PROTEIN

• An organic compound that contains the

elements carbon, hydrogen, oxygen and

nitrogen arranged into amino acids linked in a

chain by peptide bonds

Amino Acids

• Building blocks of protein

• Contains hydrogen atom, an amino group,

acid group and a distinctive side group

• There are about 20 different amino acids.

• Can be broken down by means of hydrolysis

Classification of Amino Acids • Essential amino acids – amino acids that the body

cannot synthesize in amounts sufficient to meet

physiological needs

• “indispensable”• TV TILL PM (tryptophan, valine, threonine, isoleucine, leucine, lysine,

phenylalanine, methionine)

• Note: histidine & arginine are considered essential

for infants

• Semi-essential amino acid– reduces the need for

a particular essential amino acid or partially

spares it

• Non-essential amino acid – amino acids that the

body can synthesize

– Ex. Alanine, arginine, asparagine,aspartic acid,

cysteine, glutamic acid, glutamine, glycine, tyrosine

etc.

Classification of Protein

According to Amino Acid Content

• Complete protein – contains all essential

amino acids in amount sufficient for growth

and life maintenance

Ex. Egg and animal proteins

• Partially complete – can maintain life but do

not support growth

ex. Wheat and legumes

• Incomplete protein – cannot support life or

growth

ex. Corn and most plant proteins

FUNCTIONS of PROTEINS:

• As building materials – for growth and maintenance

ex. Skin, muscles (actin & myosin), hair (keratin),

tendons & bone matrix (collagen)

• As enzymes – facilitates chemical reactions in the

body ex. Digestive enzymes

• As hormones – regulates body processes

• As antibodies – inactivates foreign invaders thus

protecting our body against infection

• As regulators of fluid balance – maintains the fluid

volume and the composition of the body fluids

• As acid-base regulators – maintains acid-base

balance in the blood and body fluid

• As transporters – transports substances such

as lipids, vitamins, minerals, oxygen around

the body

• As source of energy – provides some fuel for

the body’s needs

– Each gram of protein yields 4 calories

PROTEIN-ENERGY MALNUTRITION

Marasmus - occurrence increases prior to age 1

Body weight may be reduced to less than 80% of the normal weight for that height

extensive tissue and muscle wasting

dry skin, loose skin folds, beading of the ribs

Irritable and voraciously hungry

Kwashiorkor - occurrence increases after 18 months

failure to gain weight

stunted linear growth

generalized edema

protuberant (swollen) abdomen

diarrhea, skin desquamation (peeling) and

vitiligo

reddish pigmentation of hair

decreased muscle mass

lethargy, apathy, and irritability

LIPIDS

• Organic compounds that are insoluble in water but

soluble in fat solvents and are utilizable by man

• Contains the elements carbon, hydrogen and

oxygen in glyceride linkage

• Yields 3 fatty acids and a molecule of glycerol

upon hydrolysis

LIPIDS

• Solid lipid is called FAT while its liquid form is

termed OIL

Classification of Fatty Acids

I. Degree of Saturation or Unsaturation

• Saturated fatty acid (SAFA) – commonly

found in coconut oil, palm oil, chocolate,

butter and animal fat

• Monounsaturated fatty acids (MUFA) – with

one double bond between 2 carbons – found in olive oil, avocado, almonds, peanuts and margarine

• Polyunsaturated fatty acids (PUFA) – with 2

or more double bonds– found in corn oil, soybean oil and fish oils

II. Essentiality

• Essential fatty acids» Arachidonic acid

» Linolenic acid (omega-6)

» Linoleic acid (omega-3)

• Non-essential fatty acids

*Trans-Fatty Acid - also called “trans-fats”- made from hydrogenation of PUFA -> changes liquid oils to solid fats

*Hydrogenated Fats- turns polyunsaturated vegetable oils into saturated fats

Functions of Fats• Source of energy

- provides 9 calories per gram

• Provide structural function

- insulation: prevents hypothermia

- protective pad & gives support to organs

- integral parts of cells and tissues

Functions of Fats

• Acts as regulator of body processes- spares protein, thiamin & niacin- supplies EFAs

- carrier of fat-soluble vitamins

• Performs other special functions- has high satiety value- contributes to flavor and palatability