Introduction
Welcome to the Unit of Micro nutrients. In this course we shall discuss the
micronutrients; vitamins and minerals. Their classifications, composition, functions, food
sources, recommended dietary allowances (RDA), bioavailability, effect of processing,
nutrition imbalances and impact.
Course Objectives
Upon completion of this course, you will be able to do the following:
1.Provide an overview of the vitamins and minerals relevant to human health.
2.Discuss the scientific rationale for defining nutritional requirements in healthy
individuals and populations, with reference to specific conditions such as pregnancy,
lactation, and older age.
3.Present current evidence for the role of key nutrients in the prevention of chronic
diseases.
4. Discuss major nutrition-related diseases in a global context.
1. INTRODUCTION TO MICRONUTRIENTS
Micro nutrients are nutrientsrequired by humans and other organisms throughout life
in small quantities to orchestrate a range of physiological functions.They are also
referred to as protective foods.They are called micronutrients because they are
needed only in minute amounts, these substances are the “magic wands” that
enable the body to produce enzymes, hormones and other substances essential
for proper growth and development. As tiny as the amounts are, however, the
consequences of their absence are severe. Iodine, vitamin A and iron are most
important in global public health terms; their lack represents a major threat to the health
and development of populations the world over, particularly children and pregnant
women in low-income countries. Micro nutrients comprise of vitamins and minerals.
The important vitamins of public health importance are vitamin A, the B vitamins,
C, D, and E while important minerals include iron, zinc and iodine and calcium.
, 1.1 VITAMINS
The vitamins are organic, essential nutrients required in tiny amounts to perform
specific functions that promote growth, reproduction, or the maintenance of
health and life.
Vita- life
Amine- containing nitrogen (the first vitamins discovered contained nitrogen)
A vitamin is an organic compound required by an organism as a vital nutrient in limited
amounts. An organic chemical compound (or related set of compounds) is called a
vitamin when it cannot be synthesized in sufficient quantities by an organism, and must
be obtained from the diet. Thus, the term is conditional both on the circumstances and
on the particular organism. For example, ascorbic acid (vitamin C) is a vitamin for
humans, but not for most other animals. Supplementation is important for the treatment
of certain health problems but there is little evidence of benefit when used by those who
are otherwise healthy.
Vitamins are found in varying quantities in different foods. Most foods contain a
variety of vitamins, but no one food contains all of them in sufficient quantities to
satisfy human requirements. Absence or relative deficiency of vitamins in the diet
can lead to a characteristic deficiency state and disease. These deficiencies can
be avoided by consuming a wide variety of foods in adequate amounts
Many act as co-enzymes or a prosthetic group of enzymes responsible for
promoting essential chemical reactions. They are often called “accessory food
factors” in view of the fact that they do not supply calories nor contribute appreciably to
body mass. Animals fed on pure mixtures of carbohydrates, fat, protein, water and
minerals fail to grow properly and thrive because, as it is now known, they lack vitamins.
Vitamins vary widely in chemical structure and in their body functions. Some are
relatively simple, while others are quite complex. With a few exceptions the body cannot
synthesize vitamins; they must be supplied in the diet or in addition to the diet. Certain
vitamins (K, thiamine, folacin and B 12) to some extent may be formed by
Welcome to the Unit of Micro nutrients. In this course we shall discuss the
micronutrients; vitamins and minerals. Their classifications, composition, functions, food
sources, recommended dietary allowances (RDA), bioavailability, effect of processing,
nutrition imbalances and impact.
Course Objectives
Upon completion of this course, you will be able to do the following:
1.Provide an overview of the vitamins and minerals relevant to human health.
2.Discuss the scientific rationale for defining nutritional requirements in healthy
individuals and populations, with reference to specific conditions such as pregnancy,
lactation, and older age.
3.Present current evidence for the role of key nutrients in the prevention of chronic
diseases.
4. Discuss major nutrition-related diseases in a global context.
1. INTRODUCTION TO MICRONUTRIENTS
Micro nutrients are nutrientsrequired by humans and other organisms throughout life
in small quantities to orchestrate a range of physiological functions.They are also
referred to as protective foods.They are called micronutrients because they are
needed only in minute amounts, these substances are the “magic wands” that
enable the body to produce enzymes, hormones and other substances essential
for proper growth and development. As tiny as the amounts are, however, the
consequences of their absence are severe. Iodine, vitamin A and iron are most
important in global public health terms; their lack represents a major threat to the health
and development of populations the world over, particularly children and pregnant
women in low-income countries. Micro nutrients comprise of vitamins and minerals.
The important vitamins of public health importance are vitamin A, the B vitamins,
C, D, and E while important minerals include iron, zinc and iodine and calcium.
, 1.1 VITAMINS
The vitamins are organic, essential nutrients required in tiny amounts to perform
specific functions that promote growth, reproduction, or the maintenance of
health and life.
Vita- life
Amine- containing nitrogen (the first vitamins discovered contained nitrogen)
A vitamin is an organic compound required by an organism as a vital nutrient in limited
amounts. An organic chemical compound (or related set of compounds) is called a
vitamin when it cannot be synthesized in sufficient quantities by an organism, and must
be obtained from the diet. Thus, the term is conditional both on the circumstances and
on the particular organism. For example, ascorbic acid (vitamin C) is a vitamin for
humans, but not for most other animals. Supplementation is important for the treatment
of certain health problems but there is little evidence of benefit when used by those who
are otherwise healthy.
Vitamins are found in varying quantities in different foods. Most foods contain a
variety of vitamins, but no one food contains all of them in sufficient quantities to
satisfy human requirements. Absence or relative deficiency of vitamins in the diet
can lead to a characteristic deficiency state and disease. These deficiencies can
be avoided by consuming a wide variety of foods in adequate amounts
Many act as co-enzymes or a prosthetic group of enzymes responsible for
promoting essential chemical reactions. They are often called “accessory food
factors” in view of the fact that they do not supply calories nor contribute appreciably to
body mass. Animals fed on pure mixtures of carbohydrates, fat, protein, water and
minerals fail to grow properly and thrive because, as it is now known, they lack vitamins.
Vitamins vary widely in chemical structure and in their body functions. Some are
relatively simple, while others are quite complex. With a few exceptions the body cannot
synthesize vitamins; they must be supplied in the diet or in addition to the diet. Certain
vitamins (K, thiamine, folacin and B 12) to some extent may be formed by
