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113Nutrition and Health
Fig. 3.1: Classification of foods
114 Social Pharmacy
Recommended daily intake. RDA of different nutrients varies
according to the age, sex, and special conditions like pregnancy
and lactating mothers.
Classification of Nutrients
Nutrients are classified into two groups based on the amount
of nutrients needed daily. These are macronutrients, which
should be consumed in fairly large amounts, and micronutrients,
which are required in small amounts only.
A. Macronutrients
Macronutrients are those nutrients that the body needs in fairly
large amounts regularly for the supply of energy. They include
carbohydrates, fats, proteins, fiber, and water. Macronutrients
provide a lot of calories. Each gram of carbohydrate or protein
provides 4 calories while fat provides 9 calories for each gram.
Carbohydrates
Carbohydrates are referred to as energy-giving foods.
Carbohydrates are needed in large amounts by the body as
they constitute the body’s main source of energy. Carbo-
hydrates are needed for the proper functioning of the brain,
kidneys, central nervous system, and muscles.
Sources: Bread, wheat, maize, rice, potatoes, banana, sugar
cane, fruits. Vegetables and nuts contain lesser amounts of
carbohydrates.
Classification of Carbohydrates
Carbohydrates are classified based on the number of sugar units
into three groups:
1. Monosaccharides
2. Disaccharides
3. Polysaccharides
Our body can easily utilize monosaccharides and disaccha-
rides (simple carbohydrates), e.g. sugar. Polysaccharides
(complex carbohydrates) are broken down into simple sugars
before use by our body, e.g. starch and cellulose.
115Nutrition and Health
Proteins
Proteins are essential for the growth and maintenance of the
body and to improve immune functions. The body cannot store
excess protein. Protein requirement is expressed in terms of
grams/kg body weight. The daily body requirement of protein
for an adult is about 1 g/kg body weight.
Proteins help make essential hormones and enzymes, in
preserving lean muscle mass and supplying energy in times
when carbohydrates are not available.
Sources: Meats, eggs, chicken, beans, ground nuts, lentils,
kidney beans, fish, milk and milk products.
Fats and Oils
Fats and oils are rich sources of energy. Fats can also make
meals more tasty and satisfying.
Sources: Meat, chicken, butter, milk products, cream, cooking
oil, cheese, fish and ground nuts.
Classification of Fats
Fats are classified into two classes—saturated and unsaturated.
Saturated fats are usually solid at cool temperatures. Excess
consumption of saturated fat can cause heart and blood vessel
problems.
Unsaturated fats are usually liquid at room temperature,
for example, sesame oil, sunflower oil, maize oil, ground nut
oil, and breast milk.
Micronutrients
Micronutrients are nutrients, which the body needs in only
small amounts regularly. These include minerals and vitamins.
Vitamins
Vitamins are complex substances that do not supply energy
directly but they do regulate many processes that produce
energy. Vitamins are divided into two groups:
i. Fat-soluble vitamins, e.g. vitamin A, D, E, and K.
ii. Water-soluble vitamins, e.g. vitamins B, and C.
116 Social Pharmacy
Our body can store fat-soluble vitamins in body fat only
while water-soluble vitamins are not stored in our body in
significant amounts.
Fat-soluble Vitamins
Vitamin A (Retinol)
Sources: Liver, fish oil, meat, carrot, spinach, papaya, mango,
tomato, dairy products and eggs. Foods fortified with vitamin A
include margarine, vanaspati, and milk.
Functions: It works as an antioxidant and may reduce the
risk for certain types of cancers, cataracts, atherosclerosis, and
other diseases. It is necessary for the normal growth of bone
and skin. It improves vision. It protects us from infections by
keeping skin and tissues in our mouth, stomach, intestines; and
respiratory, genital, and urinary tracts healthy.
Deficiency: Night blindness, xerophthalmia, dry scaly skin;
and poor growth. The deficiency of vitamin A may lead to night
blindness, xerophthalmia, dry skin, corneal scarring, corneal
ulcer, corneal xerosis, conjunctival xerosis, sterility, Bitot’s
spots, keratomalacia, growth impairment, and keratinization.
Daily requirement: From age 14 onward, the RDA is 1000 g
retinol activity equivalents (RAE) of vitamin A for males, and
800 g RAE for females. During pregnancy, the recommen-
dation is 770 g per day while during breastfeeding feeding
recommended daily RAE is 1200 g.
Vitamin D (Calciferol)
It is also known as the Sunshine Vitamin. Vitamin D
2
(calciferol)
and vitamin D
3
(cholecalciferol) are nutritionally important
forms of vitamin D.
Sources: Skin can make vitamin D on exposure to sunlight.
Other sources of vitamin D are egg yolk and fish liver oils,
milk, and butter. Cheese, some fish (like sardines and salmon),
fortified breakfast cereals, and margarine also contain small
amounts of vitamin D.
Functions: It promotes the absorption of two minerals, viz.
calcium and phosphorus from the gastrointestinal tract and
117Nutrition and Health
helps in the formation of bones and teeth. It helps to deposit
these minerals in bones and teeth, making them stronger and
healthier. Additional vitamin D must be available through the
diet in places where solar radiation is insufficient.
i. It is helpful in the treatment of psoriasis.
ii. It has an immunomodulatory function.
iii. It prevents coronary artery diseases.
iv. It is useful in some types of cancers.
Deficiency: Vitamin D deficiency is responsible for rickets in
growing children and osteomalacia in adults. Both diseases are
common in India.
Daily requirement: The daily requirements of vitamin D are
2.5 g (100 IU) for adults, 5 g (200 IU) for infants and children,
and 10 g (400 IU) during pregnancy and lactation. An
International Unit (IU) is the amount of a substance that has a
certain biological effect. One IU is the biological equivalent of
0.025 g cholecalciferol or ergocalciferol.
Vitamin E (Tocopherol)
It occurs as alpha (), beta (), gamma (), and delta ()
tocopherols.
Sources: The richest sources of vitamin E are vegetable oils
(sunflower oil, soybean oil, peanut oil, wheatgerm oil) seed
oils and wheat germ oil, green leafy vegetables, and fats of
vegetable origin.
Functions: It works as a good antioxidant and helps to reduce
the risk of many health problems, such as some types of cancer.
It prevents coronary artery diseases and is helpful in
myocardial infarctions. It prevents hemolysis. It is essential for
normal functioning of reproductive organs.
Deficiency: Reproductive failure, mild hemolytic anemia,
retinopathy, neuropathy, myopathy.
Daily requirement: The RDA for males is 10 mg/day and for
females is 8 mg/day. Depending on their age children need
less vitamin E. During pregnancy, women need 15 mg daily;
during breastfeeding, the recommendation goes up to 19 mg
daily.
118 Social Pharmacy
Vitamin K
Sources: Green leafy vegetables such as spinach and broccoli,
milk, meat, eggs, cereal, fruits, and other vegetables provide
smaller amounts.
Functions: Vitamin K helps in blood clotting. It helps to make
proteins that cause blood to form a clot, when there is bleeding.
It also promotes the formation of some other body proteins for
our blood, bones, and kidneys. Vitamin K is synthesized by
bacteria in the large intestine.
Deficiency: Hypoprothrombinemia, hemorrhagic manifes-
tations, red sports and rashes all over the body.
Daily requirement: 120 g/day for men and 90 g/day for
women. The recommendations remain the same during
pregnancy or breastfeeding.
Table 3.1: Major food sources and their functions.
Nutrient Major food sources Function
Vitamin A Liver, egg yolk, meat, cod Preserves integrity of epi-
or shark liver oil, dark thelial cells; formation of
green/deep yellow vege- rhodopsin for vision in
tables and fruits dim light; wound healing,
growth, antioxidant, and
normal immune function.
Vitamin D Egg yolk, milk, liver, fatty Bone formation; promotes
fish, sunlight the absorption of calcium
and phosphorus in the
intestine, immunomodu-
latory function, and
prevents coronary artery
diseases
Vitamin E Vegetable oils; liver; egg Antioxidant, coenzyme,
yolk; butter; green leafy neuromuscular function,
vegetables; whole-grain prevents coronary artery
bread, cereals, and other diseases, helpful in myo-
fortified or enriched grain cardial infarctions, pre-
products vents hemolysis
Vitamin K Infant formula, vegetable Catalyzes prothrombin
oils, green leafy vegetables, synthesis required in the
pork, eggs, intestinal synthesis of other blood
bacteria clotting factors
119Nutrition and Health
Water-soluble Vitamins
Vitamin B
1
(Thiamine)
Sources: Cereals, legumes, pulses, nuts, yeasts, whole-grain,
pork, meat, eggs, liver, kidney, nuts, fish. It is also present in
small amounts in milk, cheese, and vegetables.
Functions:
i. It is involved in nerve impulse transmission.
ii. It is also essential for repair and growth of tissues.
Deficiency: Beriberi.
Daily requirement: The RDA for thiamine is tied to our energy
needs: 1.2 mg daily for males aged 14 through adulthood. For
females, the recommendation is 1 mg daily from ages 14–18
and 1.1 mg daily from age 19 onwards. During pregnancy and
breastfeeding, the recommended amount may increase up to
1.4 mg daily.
Vitamin B
2
(Riboflavin)
Sources: Milk and other dairy products, liver, kidney, and heart,
eggs, green leafy vegetables, and nuts. The riboflavin content
of pulses and cereals can be increased by germination.
Functions:
i. It helps to produce energy in all cells of our body.
ii. It helps in the conversion of tryptophan amino acid in
our food into niacin.
iii. It helps in RBC production.
Deficiency: Cheilosis, angular stomatitis, glossitis, seborrheic
dermatitis, scrotal deformities, eye disorders (including
cataracts), and a sore, red tongue.
Daily requirement: Like thiamine, the RDA for riboflavin is
tied to our energy needs. Adult men need 1.3 mg daily while
adult women need 1.1 mg daily. During pregnancy, the
recommendation is 1.4 mg while during breastfeeding the
amount goes up to 1.6 mg daily.
Vitamin B
3
(Niacin)
It is also known as nicotinic acid. Niacin is readily converted
to niacinamide (nicotinamide) in the human body.
120 Social Pharmacy
Sources: Poultry, fish, meat, liver, kidney, cereals yeast, beef,
nuts, butter, whole grains, and legumes are typically good
sources of niacin. Niacin is also added to many enriched and
fortified grain products.
Functions: It reduces hyperlipidemia since it reduces LDL
cholesterol (bad cholesterol) and increases HDL cholesterol
(good cholesterol).
1. It is essential for the metabolism of carbohydrates, fat, and
protein.
2. It is required for the normal functioning of the skin,
intestinal, and nervous systems.
3. It helps the enzymes to function normally in the body.
Deficiency: Pellagra, fatigue, anorexia, weakness, mild
gastrointestinal disturbance, anxiety, irritability and
depression, dermatitis.
Daily requirement: Niacin recommendations are expressed
as niacin equivalents (NE). The advice for adult males is 16 mg
NE/day, and for adult females, 14 mg NE/day. During
pregnancy, 18 mg NE/day is advised while during breast
feeding, 17 mg NE/day is recommended.
Vitamin B
6
It refers to three pyridines: Pyridoxine, pyridoxal, and
pyridoxamine. In animal products, vitamin B
6
is found largely
as pyridoxal and pyridoxamine. In plants the main form of
vitamin B
6
is pyridoxine.
Sources: Chicken, fish, pork, rice, liver, and kidney are the
best sources of vitamin B
6
. Green vegetables, whole grains,
soybeans, peanuts, bananas, bran of cereals, and legumes also
supply reasonable amounts of vitamin B
6
.
Functions:
i. It helps our body to make non-essential amino acids, or
protein components, chemicals including insulin,
hemoglobin, and antibodies that fight infection.
ii. It is important in protein metabolism.
Deficiency: Vitamin B
6
deficiency causes dermatitis, peri-
pheral neuritis, retarded growth, loss of hair, premature
121Nutrition and Health
graying of hair, convulsions, depression, nausea, or greasy and
flaky skin.
Daily requirement: The RDA of vitamin B
6
is 1.3 mg daily for
adult males as well as females through age 50 years. After age
50, the RDA increases to 1.7 mg daily for males and 1.5 mg for
females. The amount increases to 1.9 mg daily during
pregnancy and 2.0 mg daily during breastfeeding.
Vitamin B
5
(Pantothenic acid)
Pantothenic acid, also called vitamin B
5
, is the combination of
pantoic acid and -alanine. As a dietary supplement ingredient,
it is commonly found as calcium pantothenate.
Sources: Meat, poultry, fish, whole-grain cereals, and legumes
are among the better sources. Milk, vegetables, and fruits also
contain varying amounts.
Functions:
i. It helps our body cells to produce energy.
ii. It helps to metabolize proteins, and carbohydrates from
food.
iii. It is also involved in the metabolism of lipids and the
synthesis of steroids.
Deficiency: Abdominal pain, soreness, nausea, personality
changes, insomnia, impaired adrenal function, weakness,
cramps in the legs, paresthesia of the hands and feet, and
impaired antibody production.
Daily requirement: The adequate intake (AI) for pantothenic
acid is 5 mg daily for ages 14–18 and adults. The AI increases
to 6 and 7 mg, respectively during pregnancy and breast-
feeding.
Vitamin B
7
(Biotin)
Sources: Egg yolk, fish, milk, yeast bread, nuts, honey, liver,
meat, and cereals are among the best sources. Biotin is
important for the health of our hair, skin, and nails.
Functions:
i. It helps our body to produce energy in cells.
ii. It helps in the metabolism of proteins, fats, and carbo-
hydrates.
122 Social Pharmacy
Deficiency: Poor growth, loss of muscular control, loss of
appetite, hair fall, weakness.
Daily requirement: The adequate intake (AI) for biotin is
30 g daily for adult males and females, including during preg-
nancy. The AI increases to 35 g daily during breastfeeding.
Vitamin B
9
(Folic acid)
Folic acid occurs either as a free or bound folate form and is
often used in combination with other B vitamins.
Sources: Fresh green leafy vegetables, cauliflower, orange
juice, lentils, dried beans, spinach, broccoli, peanuts, avocados,
liver, kidney and yeast. It is also synthesized by intestinal
bacteria.
Functions: It helps to:
i. make new body cells,
ii. form hemoglobin in red blood cells,
iii. protect against heart disease,
iv. lower the risk of delivering a baby with neural tube
defects such as spina bifida,
v. control plasma homocysteine levels, which is asso-
ciated with increased risk of cardiovascular disease,
and
vi. increases appetite.
Deficiency: Megaloblastic anemia, growth impairment neural
tube defects such as spina bida (the neural tube in an embryo
becomes the spinal cord and brain), anencephaly in pregnant
women, and infertility or even sterility.
Daily requirement: For folate, the RDA for males from age 14
through adulthood is 400 g daily. Women capable of becoming
pregnant (14 to 50 years) should get 400 g of folic acid daily
from fortified foods, vitamin supplements, or a combination
of the two, in addition to the folate found naturally in certain
foods. Pregnancy increases the recommended amount to
600 g daily and during breastfeeding, 500 g is advised.
Vitamin B
12
(Cyanocobalamin)
Cyanocobalamin or vitamin B
12
is a water-soluble vitamin
synthesized exclusively by microorganisms.