SESSION 2

PRACTICAL NUTRITION FOR FIELD WORKERS (1)

Objective

By the end of this session, field workers will appreciate the importance of adequate household food supplies as a basic condition for the nutritional well-being and health of all family members. They will:

• understand the meaning of the term "nutrition";
• know the differences in the composition of foods commonly eaten;
• know the differences in the nutritional requirements of different family members;
• understand the effects of inadequate food intake on nutritional status and health.

FIGURE 2.1
A family's nutritional well-being depends on access to a nutritious diet at all times

OVERVIEW

Most people eat because they feel hungry. Although the sensation of hunger tells them to eat, it does not tell them what to eat. Field workers promoting home gardening need to have a basic understanding of nutrition, in order to help household members grow and select a variety of foods, develop healthy eating habits and lead active and healthy lives.

Nutritional well-being requires access to enough nutritious and safe food to meet the dietary needs of all members of the household throughout the year. Food security and nutritional well-being mean more than just producing enough food. People must also have knowledge about nutrition, especially of what kinds of foods to eat and how to prepare them in the right quantities and combinations, and in a way that is safe and clean.

It is important for mothers to know about proper feeding practices and to have enough time for food preparation and frequent child feeding. In addition, access to sufficient clean water and a healthy environment mean less risk of infectious diseases. A healthy body is better able to utilize foods, because illness can interfere with nutrient absorption, especially such illnesses as diarrhoea, parasitic infections and measles.

This session defines the meaning of nutrition and identifies the main nutrients in commonly eaten foods. It discusses the role and importance of nutrients in different foods, the nutritional needs of different household members and what happens to the body if people do not follow a healthful diet, practise adequate personal and food hygiene or have access to adequate and safe drinking-water or health care.

ACTIVITIES

Before this training session, the trainer must convert all quantities given in Table 2.4, "Food quantities that meet daily energy and nutrient requirements of different household members", into locally appropriate household measures.

Discussion. The trainer states the objective of the session, and then, using the appropriate technical notes, initiates a discussion based on the following questions:

• What is nutrition about?
• What are the nutrients in foods and what are they for?
• Do the nutritional needs of different household members vary, and if so, how and why?
• What happens if the nutritional needs of different household members are not met?

Discussion of the value of different foods. Keeping in mind the home garden crops identified during the first household visit (Checklist 1) and other foods grown on the family farm, participants should discuss the importance of each crop and how it is used in meal preparation. They should then classify the foods by their key nutrient(s), for example, energy (carbohydrates and fat), protein, vitamins and minerals. After this discussion and classification, the participants should compare their knowledge of food nutrients with the information given in Table 2.5, "Home garden crops that are rich in key nutrients".

Discussion of dietary deficiencies. The trainer reproduces Table 2.1, "Symptoms of nutritional deficiencies", on the flip chart and invites the participants to discuss, based on their knowledge and experience, what happens to the body when a person does not get enough energy producing food, or when a specific nutrient is lacking or inadequate in the diet.

TABLE 2.1
Symptoms of nutritional deficiencies

The field workers then read Information Sheet 2, "Food and nutrition problems". Together they adjust their responses accordingly, and the trainer answers any questions that arise. The trainer then conducts a practical session on assessing child nutritional status using measures of mid-upper-arm circumference (MUAC). Prior to this session the trainer should invite several mothers with their children (aged one to five years) to be present. Participants practise taking mid-upper-arm-circumference measurements on the children using a MUAC strip or a simple tape measure.

Exercise. After having reviewed the signs and symptoms of malnutrition and micronutrient deficiencies, the trainer initiates a discussion of the causes of malnutrition and other nutritional deficiencies that are present in the community. The trainer facilitates this session and helps the participants build a causal model or problem tree (a diagram of the causes of malnutrition and how they are interrelated) that focuses on what they consider to be the causes of malnutrition and nutritional deficiencies in the communities they are familiar with (see Figure 2.2). Creating a causal model helps field workers better understand the interactions of the different factors that influence nutritional outcomes. It will also assist them later in adjusting Checklist 2 (which is found in Session 7) in preparation for the second field visit to include issues and questions on the local food and nutrition situation.

FIGURE 2.2
Causal model of malnutrition

MATERIALS REQUIRED

• flip chart
• Checklist 1
• Information Sheet 2, "Food and nutrition problems"
• cards of varying colours and shapes (round, oval, square) for visualizing the causes of malnutrition
• Table 2.1, "Symptoms of nutritional deficiencies", Table 2.2 "Nutritional values of raw and processed foods commonly consumed", Table 2.3 "Daily requirement of energy, protein, fat, vitamins A and C and iron for different sex and age groups",
  Table 2.4, "Food quantities that meet daily energy and nutrient requirements of different household members", and Table 2.5, "Home garden crops that are rich in key nutrients"
• MUAC strip or tape measure

TECHNICAL NOTES

Nutrition is about food and how it is used in the body

Nutrition is an area of knowledge and practice concerned with food and how it is used in the body. This includes how food is produced, collected, bought, processed, sold, prepared, shared and eaten, as well as how food is digested, absorbed and used by the body, and how it finally influences well-being.

If eaten in the right amounts and combinations, food provides all the nutrients the body needs for proper growth, functioning and mental development, and to keep people healthy.

Food is made up of a combination of nutrients

Food is made up of nutrients such as carbohydrates, proteins, fats, vitamins and minerals. Vitamins and minerals are called micronutrients. They are needed in much smaller amounts than protein, fat and carbohydrates but are essential for good nutrition. A healthful diet is one that supplies adequate amounts of all these nutrients.

All foods from plants and animals contain a mixture of nutrients. Each food, however, has a different amount of each nutrient. Except for breastmilk in the first six months of life, no single food provides all the required nutrients.

To achieve a balanced diet and stay healthy, people must eat a variety of foods each day. For example, staple foods such as cassava, yams, taro (cocoyams), sweet potatoes and plantains are good sources of carbohydrates, but contain relatively little protein. Cereals, including maize, sorghum, millet and rice, in addition to being rich in carbohydrates, also contain significant amounts of protein and B vitamins. Legumes such as cowpeas, pigeon peas, soybeans, beans, groundnuts, bambara groundnuts and horsebeans are rich sources of protein and iron, while soybeans and groundnuts are also good sources of fat. Roots and tubers, legume seeds and cereals are relatively poor sources of vitamins A and C, while fruits and vegetables, including cassava, cowpea, bean and sweet potato leaves, contain significant amounts of vitamins and minerals.

To balance their diets, people must complement staple foods with legumes or foods from animal sources that are rich in protein and oil or fat; vegetables such as pumpkin leaves or amaranth; and orange- and yellow-coloured fruits and vegetables such as mangoes, papayas and pumpkin, which are extremely rich in vitamin A. Information Sheet 3, "Recipes for nutritious dishes", provides a family mixed meal guide, which gives suggestions for the alternative types of food mixtures that constitute a nutritionally adequate meal.

The nutrient content of food changes with the degrees of freshness of the food and the methods of processing, preserving and preparing it. For instance, if the outer skin of cereal grain is removed during milling, most of the cereal's minerals and vitamins are lost, and the vitamin C content of vegetables diminishes if the vegetables are overcooked. Table 2.2 provides the nutritional values of some of the garden and field crops commonly grown in different parts of Africa, including processed foods such as sugar, oils and maize flour. Appendix 2 provides a detailed table of the nutritional value of most of the foods consumed in Africa.

Nutrients are needed to keep the body active and healthy

Most farmers know from experience that crops need certain nutrients in order to grow well. Plants get these nutrients from the soil or from fertilizer. In a similar way, people require certain types and quantities of nutrients from their diets, from the time a baby is conceived in the mother's womb and throughout life.

Each type of nutrient serves particular functions: carbohydrates and fats are the main sources of food energy. About 50 percent of the carbohydrates and fats in the body are "burned", or broken down, to produce the energy the body needs to perform different physical activities; the rest is used by the body for growth and general maintenance and in the renewal of its tissues.

Fat is a particularly concentrated source of energy and contains twice as many kilocalories³ as carbohydrates and proteins. Fats, in addition to providing energy, are also needed for the absorption and use of some vitamins, especially vitamin A. Proteins are needed to build and maintain muscle, blood, skin, bones and other tissues - they are the primary building blocks of the body. Protein is especially important for children, and pregnant and lactating women.

Vitamins and minerals help the body work properly and stay healthy. They contribute to tissue repair, and ensure children's healthy growth, mental development and protection from infection.

Inadequate dietary intake in young children slows down or stops growth, weakens the body and impedes intellectual development. Children of school age who do not get enough nutritious food are unable to concentrate and do not learn as well as well-nourished children.

TABLE 2.2
Nutritional values of raw and processed foods commonly consumed (100 g edible portions)

An inadequate diet can affect older children and adults of the household as well. Many households have limited labour available for work on farmland. A poor diet results in reduced work capacity and illness. Illness means visits to the health centre, which means lost working time and lost money. These losses can be reduced or prevented if everyone in the household eats enough healthful food, drinks clean water and practises good hygiene.

Inadequate dietary intake can also have far-reaching effects on the socio-economic development of a country. This is a situation that no country can afford. Actions are needed, therefore, that address the causes of inadequate dietary intake and improve the nutritional status and health of children and adults. For more information on specific food and nutritional problems, see Information Sheet 2, "Food and nutrition problems".

The amount of nutrients needed varies for each person and at different stages of life

The amount of energy and nutrients people require from their diets in order to stay healthy and active varies with age, sex, pregnancy and lactation, level of activity and state of health.

The most critical stage of human development is from conception to about three years of age, a period when physical growth occurs most rapidly. It is crucial, therefore, that small children and pregnant and lactating women in particular receive the right amount of nutritious food in order to ensure proper growth, brain development and resistance to infection of the foetus and young child.

Food given to children in the first year of life must have sufficient energy and nutrients to support rapid growth and development. A child under one year of age, for example, requires almost twice the amount of energy per kilogram of body weight as a teenager or adult. For example, a child less than one year needs 110 kcal/kg body weight per day; a child less than five years: 95 kcal/kg body weight per day; a 12-year-old male: 64 kcal/kg body weight per day; and a 16-year-old male: 44 kcal/kg body weight per day.

When breastmilk becomes inadequate to support healthy, normal growth, at about six months of age, children must be given foods that are nutrient dense (i.e. with high concentration of nutrients relative to the volume measure). This is particularly important because children at this age have extremely small stomachs and can take in only limited quantities of food at a time. Frequent feeding (four to five times a day) with foods, in addition to breastmilk, is therefore important to ensure that children get sufficient energy and nutrients to grow normally and stay healthy. Mothers should continue breastfeeding on demand until children are 18 months to two years of age.

Pregnant women need additional food of good quality to meet the nutrient needs of a growing foetus (baby in the womb). Lactating mothers require additional energy and nutrients to produce enough milk for a small child.

Table 2.3 shows the different nutritional requirements for a six-person household (father, mother and four children). The nutritional requirements of a woman of child-bearing age, a pregnant woman and a lactating woman have been included to provide a comparison of requirements among these three different physical states. The table mentions some of the vitamins and minerals essential for health and development, but there are many others that are important and must be provided in a daily diet.

Note: In Africa the dietary intake of fat or oils is often low (i.e. less than 10 percent) because refined oils and animal foods that are sources of fat are expensive. Everyone needs to eat some fat, however, because everyone, especially children, requires essential fatty acids. Also fat makes food less bulky and helps the body in its absorption of some vitamins, especially vitamin A. As a general rule, about 15 to 35 percent of kilocalories should be obtained from fat. Foods that are rich in fat include groundnuts and oil crops, such as sesame and sunflower seeds. Both coconut and red palm oil are excellent sources of essential fatty acids. Special efforts are needed to assist household to increase the production of oil- or fat-containing crops so as to increase their supply and enhance access at household level.

TABLE 2.3
Daily requirement of energy, protein, fat, vitamins A and C, and iron for different sex and age groups

Note: 1 g protein or 1 g carbohydrates = 4 kcal; 1 g fat = 9 kcal; 1 g alcohol = 7 kcal.
Fat requirements were calculated to provide 25% of average energy requirements.
^* The assumption is that breastmilk satisfies this child's fat-intake requirements.
^** Data refer to male children.
^a The requirements are based on a low iron availability diet (i.e. 5% of iron absorbed).
^b Bioavailability of iron during this period varies greatly.
^c It is recommended that iron supplements be given to all pregnant women because of the difficulties in correctly evaluating iron status in pregnancy.
Sources: James, W.P.T. and Schofield, E.C. (1990). Human energy requirements: a manual for planners and nutritionists. Published for FAO by Oxford University Press, Oxford.
FAO/WHO/UNU (1985). Protein and energy requirements. WHO, Geneva, 1985.
FAO/WHO (1988). Expert Consultation Report on the Requirements for Vitamin A, Iron, Folate and Vitamin B₁₂.
FAO (2000). Preliminary Report. Joint FAO/WHO Expert Consultation on Human Vitamin and Mineral Requirements.

Daily household food requirements expressed in household measures

Since the participants may not have access to scales, the daily food requirements make more sense if expressed in terms of food quantities, using local household measures. Table 2.4 gives an example of the approximate food quantities (in grams) needed to construct a basic low-cost diet that meets the energy and nutrient needs of different household members. Only a few food items have been used to keep the diagram simple; however, people should eat a variety of foods, including fruits, every day. Trainers should convert these quantities into the local measures (e.g. cups, spoons, mudus, olodo or tiers)⁴ that are commonly used in a given home or at the local market.

TABLE 2.4
Food quantities that meet daily energy and nutrient requirements of different household members

^* In a cereal-based diet, about one-third of the required fat comes from cereals and the rest from other foods, whereas in a root-and-tuber-based diet, virtually all the fats come from relishes or snacks.

Based on information provided in Table 2.4, a household comprising a father, mother (lactating) and four children aged 2, 5, 12 and 14 years would require about 2.3 kg maize flour, 1.1 kg low-fat legumes, such as beans, and about 0.7 kg green leafy vegetables. During meal preparation, oil is often added, when available, to relishes or sauces to make them tasty. The quantities of oil vary depending on what the family can afford, but at least 200 g (1 cup) per day for cereal-based diets and 300 g (1.5 cups) per day for root-and-tuber-based diets are needed to meet nutritional needs, enhance the foods' taste and palatability (i.e. make eating more pleasurable), and make swallowing easier. Pounded groundnuts, melon seeds and sesame seeds are often used as alternatives and added to vegetable relishes or soups, making these dishes tastier. Energy-rich snacks for children complement main meals and add energy to the diet. Fruits, which are rarely eaten as part of a meal, should be included, especially if the diet lacks micronutrients.

Depending on the usual meal frequency, the recommended quantities can be spread out over two or three meals per day for adults. Because of their small stomach size, children under five years of age need more meals and should be given snacks between the main family meals. These snacks can be in the form of leftovers from the main meals. For more information on preparing nutritious and tasty family meals, and for recommendations for infant and child feeding, see Session 3 and Information Sheets 4 and 5.

Table 2.5 provides a guide to home garden foods that are rich in energy as well as in some key nutrients that are frequently lacking in rural diets but are essential for good health. It also provides information about which foods can be used as substitutes for others and which foods can be used to enrich dishes and meals.

A practical approach to healthful eating is to ensure the consumption of a variety of foods, focusing on the staple foods, as well as those that are ingredients for relishes, West African soups or stews. The relish, soup or stew often provide additional energy (from beans, peas, groundnuts and oil), additional protein (from beans, peas, groundnuts, meat and fish) and essential micronutrients (from vegetables, fruits, meat and fish). Using the family mixed meal guide provided in Information Sheet 3, together with the food quantities given in Table 2.4, it is possible to plan family meals that are nutritious, tasty and in keeping with local eating patterns and customs.

TABLE 2.5
Home garden crops that are rich in key nutrients

· Absorption of iron in these foods is increased by combining them with vitamin- C- rich foods, for example, by eating an orange or guava at the end of a meal.

⁴ Household measures used in some parts of West Africa.