Nutrition Module: 1. Food, Diet and Nutrition an Overview

Study Session 1  Food, Diet and Nutrition: an Overview

Introduction

In this study session, you will learn about some of the basics of nutrition. You will learn what is meant by food and diet as well as the meaning of nutrition and nutrients in general. What food does to our body and how the body uses nutrients is also explained. Estimates of the eligible population for nutritional care and support are provided, using calculations from the Ethiopian census data. Finally, the relationship between health, nutrition and development is described, linking them with the Millennium Development Goals. The overall purpose of this session is to teach you some of the basics about nutrition that you will be able to use in your work and will inform your learning throughout the whole of the Module.

Learning Outcomes for Study Session 1

When you have studied this session, you should be able to:

1.1  Define and use correctly all of the key words printed in bold. (SAQs 1.1 and 1.2)

1.2  Know how to estimate the number of children under two and under five years of age, as well as pregnant and lactating mothers in your community in one year. (SAQ 1.3)

1.3  Briefly describe the differences and relationships between food, diet and nutrients. (SAQs 1.1 and 1.2)

1.4  Understand how food nourishes the body. (SAQs 1.2 and 1.4)

1.5  Explain the relationship between nutrition and health, and nutrition and development. (SAQs 1.4 and 1.5)

1.1  Maternal and childhood undernutrition

The first Millennium Development Goal (MDG 1) calls for the eradication of extreme poverty and hunger, and its achievement is crucial for national progress and development. All the Millennium Development Goals are connected so failing to achieve this goal jeopardises the achievement of other MDGs, including goals to achieve universal primary education (MDG 2), reduce child mortality (MDG 4) and improve maternal health (MDG 5).

One of the indicators used to assess progress towards MDG 1 is the prevalence of children under five years old who are underweight, or whose weight is less than it should be for their age. To have adequate and regular weight gain, children need enough good-quality food to meet their nutritional requirements, they need to stay healthy and they need sufficient care from their families and communities.

To a great extent, achieving the MDG target on underweight in children depends on the effective implementation of large-scale nutrition and health programmes that will provide appropriate food, health and care for all children in a country. Your role as a Health Extension Practitioner is, therefore, key in attaining these goals.

1.1.1  The global burden of childhood and maternal undernutrition

Undernutrition contributes to more than 50% of all deaths in children under the age of five. It does this by impacting on children’s strength and making illness more dangerous. An undernourished child struggles to withstand an attack of pneumonia, diarrhoea or other illness — and illness often prevails. Undernutrition is caused by poor feeding and care, aggravated by illness. The children who survive may become locked in a cycle of recurring illness and slow growth, diminishing their physical health, irreversibly damaging their development and their cognitive abilities, and impairing their capacities as adults. If a child suffers from diarrhoea — due to a lack of clean water or adequate sanitation, or because of poor hygiene practices — it will drain nutrients from his or her body.

Chronic undernutrition (meaning low height for age, also known as stunting) in early childhood also results in diminished mental and physical development, which puts children at a disadvantage for the rest of their lives. They may perform poorly in school, and as adults they may be less productive, earn less and face a higher risk of disease than adults who were not undernourished as children. For girls, chronic undernutrition in early life, either before birth or during early childhood, can later lead to their babies being born with low birth weight, which can again lead to undernutrition as these babies grow older. Thus a vicious cycle of undernutrition repeats itself, generation after generation.

The global burden of stunting is far greater than the burden of underweight. Based on the latest available data, in the developing world, the number of children under five years old who are stunted is close to 200 million, while the number of children under five who are underweight is about 130 million.

Infants with low birth weight may never recover from their early disadvantage. Like other undernourished children, they may be susceptible to infectious disease and death, and as adults they may face a higher risk of chronic illness such as heart disease and diabetes. Thus the health of the child is inextricably linked to the health of the mother. In turn, the health of the mother is linked to the status a woman has in the society in which she lives. In many developing countries, the low status of women is considered to be one of the primary reasons for undernutrition across the life cycle.

1.1.2  Childhood and maternal malnutrition in Ethiopia

Malnutrition is one of the main health problems facing many women and children in Ethiopia. Ethiopia has the second highest rate of malnutrition in Sub-Saharan Africa (SSA). Ethiopia faces the four major forms of malnutrition: acute and chronic malnutrition, iron deficiency anaemia (IDA), vitamin A deficiency (VAD), and iodine deficiency disorder (IDD). The 2005 Ethiopian Demographic and Health Survey (DHS) highlights the different levels of deficiencies in different age groups (see Table 1.1).

Vitamin A deficiency is the most common cause of preventable blindness. The 2005 national IDD survey showed a goitre (enlargement of the thyroid gland in the front of the neck) of over 35%; both of these are considered emergency proportions by WHO standards. There is a marked decrease in the number of Ethiopian households that consume iodised salt compared with a decade ago, leading to increased iodine deficiency disorder.

The prevalence of low birth weight (LBW) in Ethiopia (14%) is one of the highest in the world. One major contributing factor for LBW is the poor nutritional status of women both before and during pregnancy, made even worse by inadequate weight gain during pregnancy.

The consequences of malnutrition for Ethiopia if no action is taken are enormous. The greatest functional consequences of malnutrition for children are increased risk of illness, and death; and for those who survive, mental impairment and reduced capacity to produce and contribute to the economy of the country. These consequences of malnutrition are often not fully appreciated because they are hidden. Based on a national study, malnutrition contributes to an estimated 270,000 deaths of under-five children each year; and VAD contributes to 80,000 children’s lives lost every year. As malnutrition and VAD weaken the immune system of children, they will be susceptible to common childhood infections and more liable to suffer from serious complications.

Beyond the individual human suffering, malnutrition reduces mental development and, thus, will mean slower learning throughout life. About 685,000 babies are born to mothers with IDD and are likely to suffer from some degree of reduced mental capacity. Malnutrition also reduces work productivity, as stunted, less educated and mentally impaired adults are less productive. It has been estimated that the annual value of the loss in productivity that can be attributed to child stunting is 2.92 billion ETB (Ethiopian Birr). Moreover, iodine deficiency, which results in irreversible impairment of intellectual capacities, has been estimated to cost the Ethiopian economy 1.35 billion ETB per year. The productivity losses due to malnutrition in Ethiopia over the next ten years will be 144 billion ETB.

When aggregated, the effects on illness, education and productivity have an enormous impact on the economic growth and poverty reduction effort of the country. Given the benefits of reducing the burden of malnutrition in Ethiopia, the government efforts to address malnutrition in a comprehensive approach can be easily justified.

The most critical time for preventing malnutrition is during pregnancy and the first two years of a child’s life. You will look at how you can plan nutritional support for mothers and babies in your community in the next section.

1.2  Planning nutritional care and support in your community

When you are planning nutritional care and support in your community, the first step is to calculate the number of children under five, and the number of pregnant and lactating women who might need nutritional care and support in one year. According to the 2007 population statistics of Ethiopia, the number of children under two years is calculated as 8% of the total population, while the number of children under five years of age is 14.6%. The Ethiopian population statistics also indicate that the number of pregnant women is 4% of the general population. This percentage is used to estimate the number of pregnant and lactating mothers in a given community. The percentages will vary to some extent between communities, but they can be used to estimate numbers with reasonable accuracy. Look at Box 1.1 which illustrates how to calculate the number of children under the age of 2 years in a kebele.

Box 1.1  Calculating the number eligible for nutritional care and support in a kebele

The percentage of children under the age of two years in a kebele of 5,000 people is calculated as follows:

1.3  Food, diet and nutrition

What we eat and drink to help keep us alive and well, to help us grow, develop, work and play is called food. Food is anything edible. It includes all foods and drinks acceptable for that particular society, culture or religion.

Food gives us a feeling of comfort and satisfaction. Eating certain foods establishes our identity. What we eat and how we eat makes up our food habit. Most of our food habits are learned in the home from our parents. As we grow up, our experience and learning help us to change some of these food habits. You are learning about food and nutrition in order to be able to teach and help mothers to change their food habits for the better.

Diet is the sequence and balance of meals in a day. It is concerned with the eating patterns of individuals or a group. Some people may eat twice in a day (breakfast and dinner); others may eat four times (breakfast, lunch, snack and dinner); still others may seem to be chewing all day long.

Nutrition is the interaction between food and the body. It is about the nutrients contained in food, and their action, interaction and balance in relation to health and disease. It is the process by which people can ingest, digest, absorb, transport, utilise and excrete food substances. In addition, nutrition is concerned with social, cultural and physiological implications of food and eating. In general, the science of nutrition is the science of showing how food nourishes the body.

A nutrient is an active chemical component in food that plays a specific structural or functional role in the body’s activity. Sugars, starches and fibre are often grouped together as they are all carbohydrates. Vitamins and minerals are needed in very small amounts and they are called micronutrients.

Almost all foods are a mixture of nutrients. They contain different amounts of sugar, starch, fibre, fat, protein, minerals, vitamins and water. Table 1.2 shows you the different nutrients, their food groups and examples of food sources found in Ethiopia.

Table 1.2  Types of nutrients and their food sources. (Photos: Dr Basiro Davey)

Nutrient	Food group	Examples of foods
Sugar Starch Fibre	Carbohydrates
Fats Oils	Fats
Proteins	Proteins
Vitamins Minerals	Micronutrients
Water	Water

1.3.1  How food keeps us healthy

Food is needed for energy and nutrients to exist, it provides energy for work, and warmth for the body. Everybody also needs food to build, maintain and repair their body. It is also required for control of body processes and for protection against disease and infections. By performing these functions, food helps us to keep healthy, warm, well-nourished, free of infections and alive.

By helping us to understand how food and nutrients work, the science of nutrition plays a fundamental role in the promotion of health, in the prevention of illness and in the restoration of health following illness or injury. Your work as a Health Extension Practitioner can be instrumental in preventing problems related to nutrition.

1.3.2  What does food do for our body?

As you just read, food contains chemical substances called nutrients and these are found in varying amounts and combinations in different foods. Nutrients are the part of food which the body uses to:

• build tissues
• produce energy
• keep healthy.

Enough food containing the necessary nutrients should be eaten every day (such as carbohydrates, proteins, water, vitamins and minerals). It is likely that you will get enough of the other nutrients (for example dietary fibre) that your body needs by doing this. No one food supplies all the nutrients the body needs. No one nutrient is more important than the others. Each nutrient does specific jobs. The nutrients work together to keep us healthy.

It is important to include fibre (roughage) in the diet because it makes the bowels work properly and provides bulk to make us feel full. Fresh fruits and vegetables, peas and beans, whole wheat flour and unrefined maize or sorghum flour give us fibre.

In the next two sections, you will learn why and how the body uses nutrients to build the body and produce energy.

1.4  The importance of nutrients

The nutrients we get from the food we eat will affect the size and shape of our body. The use of nutrients to build tissues and supply energy at various stages of our life is explained here.

1.4.1  Using nutrients to build tissue

The human body consists of different types of nutrients. For example, a person who weighs 50 kg consists of 31 kilograms of water, 9 kg of protein, 7 kg of fat and 3 kg of minerals. Therefore, besides water, the most important building nutrient is protein. Fat is also important to build cells and energy stores. Some minerals are important, for example calcium, which is necessary to build bones and teeth, and iron which helps to build haemoglobin in the blood. Table 1.3 shows the percentages of each of the nutrients in the body.

1.4.2  Using nutrients to build the body

For growth: A child starts to grow as a single cell inside its mother. The cell absorbs nutrients; it grows and divides into two cells. The cell uses nutrients as building materials for the new cell and other nutrients for energy to do the work of building. Each cell then absorbs more nutrients to grow larger and divide again. The cells continue to absorb nutrients and to grow and divide until there are millions of cells which form different tissues such as skin, muscle and bone. The child’s body also makes fluids such as blood, which nourishes and protects the cells.

For pregnancy: During pregnancy, a woman needs body building nutrients to:

• provide the baby and placenta with nutrients to grow
• increase the size of her uterus and breasts
• make more blood and stores of fat that can be mobilised during lactation, and other nutrients.

To secrete fluids: The body has to keep making fluids such as saliva, digestive juices, tears and breastmilk because they are continually used up.

To replace cells: Most cells live only a short time. The body must build new cells to replace those that die. The need to replace cells continues throughout life. Skin is a good example. The outside layer of the skin is already dead. All the time new cells are growing under the dead cells to replace them. When you wash and dry yourself, you remove the dead cells.

If you wear shoes for a long time you get holes in the soles. But if you walk without shoes, you do not get holes in your feet, because new skin cells grow under the old cells to replace them.

To repair tissues: After injury or illness, the body makes new cells to repair the damaged tissues.

1.4.3  Using nutrients to produce energy

When you turn on the engine of a car, the petrol combines with oxygen and ‘burns’ to make energy. The energy makes the car move, and it also makes the engine warm. Similarly, the body ‘burns’ nutrients to make energy. Sometime people are surprised to learn that nutrients are ‘burning’ inside their bodies. Nutrients do really burn – but in a different way from a fire so that there is no fire or smoke.

Starch, sugar and fat are made of the elements carbon, hydrogen and oxygen. When they ‘burn’ in the cells, they combine with oxygen from the air that we breathe in. They release energy, and they change into carbon dioxide and water, which we breathe out. Table 1.4 shows the different ways our body uses energy.

Table 1.5 below provides you with a summary of the way our body uses nutrients.

1.5  Food and nutrition: cultural and religious taboos

Within all communities there are often stories and a rich heritage of beliefs and customs around the subject of food. Sometimes, however, these cultural features become the cause of problems. Within Ethiopian society some problems have been identified including:

• Pregnancy — women do not receive enough care; the work burden of the mothers is not alleviated.
• Breastfeeding — colostrum discarded; the newborn is forced to swallow butter.
• Infancy/childhood — children eat last; the quality of their food is poor.
• Women — gender bias; women eat last and only have the leftovers.

1.6  Nutrition, health and development

You have probably heard the saying ‘You are what you eat’. The health of your body depends on what you feed it on, just as a healthy plant or anything else will grow better in rich soil and good conditions. As you have learnt in this study session, everybody needs a variety of foods which contain enough different nutrients to keep them alive and healthy. This means that nutrition is a foundation for health and development. Better nutrition means stronger immune systems, less illness and better health for people of all ages. Healthy children learn better and grow better. Healthy people are stronger, more productive, and better able to break cycles of poverty and realise their full potential. The relationship between nutrition, health and development is best described using the MDGs.

In this study session you have learnt about the magnitude of nutritional problems in Ethiopia. In addition, you have gained some knowledge about the basics of nutrition that you will use in your work. The summary below will enable you to remember the main points.

Summary of Study Session 1

In Study Session 1, you have learned that:

1. Ethiopia is affected by a high level of undernutrition (acute and chronic malnutrition).
2. Vitamin and mineral deficiencies (vitamin A, iodine and iron) affect a huge proportion of children and mothers. The health and economic consequences are immense for the country.
3. The body uses different nutrients for different reasons, such as an energy source, to build cells, make fluids and protect against infection.
4. It is necessary to calculate the number of children under two or under five and pregnant mothers in your kebele who might need nutritional care and support.
5. There are community customs and traditional beliefs that impact on feeding habits and may not always promote best nutritional outcomes, particularly for women and children.
6. Good nutrition has positive outcomes for the health and development of the population. Health Extension Practitioners have an important role to play in providing information about nutrition to families in their communities.

Self-Assessment Questions (SAQs) for Study Session 1

Now that you have completed this study session, you can assess how well you have achieved its Learning Outcomes by answering the questions below. Write your answers in your Study Diary and discuss them with your Tutor at the next Study Support Meeting. You can check your answers with the Notes on the Self-Assessment Questions at the end of this Module.