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Infant and Young Child Feeding: Model Chapter for Textbooks for Medical Students and Allied Health Professionals. Geneva: World Health Organization; 2009.

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Infant and Young Child Feeding: Model Chapter for Textbooks for Medical Students and Allied Health Professionals.

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SESSION 3Complementary feeding

3.1. Guiding Principles for Complementary Feeding

After 6 months of age, it becomes increasingly difficult for breastfed infants to meet their nutrient needs from human milk alone. Furthermore most infants are developmentally ready for other foods at about 6 months. In settings where environmental sanitation is very poor, waiting until even later than 6 months to introduce complementary foods might reduce exposure to food-borne diseases. However, because infants are beginning to actively explore their environment at this age, they will be exposed to microbial contaminants through soil and objects even if they are not given complementary foods. Thus, 6 months is the recommended appropriate age at which to introduce complementary foods (1).

During the period of complementary feeding, children are at high risk of undernutrition (2). Complementary foods are often of inadequate nutritional quality, or they are given too early or too late, in too small amounts, or not frequently enough. Premature cessation or low frequency of breastfeeding also contributes to insufficient nutrient and energy intake in infants beyond 6 months of age.

The Guiding principles for complementary feeding of the breastfed child, summarized in Box 1, set standards for developing locally appropriate feeding recommendations (3). They provide guidance on desired feeding behaviours as well as on the amount, consistency, frequency, energy density and nutrient content of foods. The Guiding principles are explained in more detail in the paragraphs below.

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Box 1

Guiding principles for complementary feeding of the breastfed child. Practise exclusive breastfeeding from birth to 6 months of age, and introduce complementary foods at 6 months of age (180 days) while continuing to breastfeed. Continue frequent, on-demand (more...)

GUIDING PRINCIPLE 1. Practise exclusive breastfeeding from birth to 6 months of age and introduce complementary foods at 6 months of age (180 days) while continuing to breastfeed

Exclusive breastfeeding for 6 months confers several benefits to the infant and the mother. Chief among these is the protective effect against gastrointestinal infections, which is observed not only in developing but also in industrialized countries. According to the WHO growth standards, children who are exclusively breastfed have a more rapid growth in the first 6 months of life than other infants (4).

By the age of 6 months, a baby has usually at least doubled his or her birth weight, and is becoming more active. Exclusive breastfeeding is no longer sufficient to meet all energy and nutrient needs by itself, and complementary foods should be introduced to make up the difference. At about 6 months of age, an infant is also developmentally ready for other foods (5). The digestive system is mature enough to digest the starch, protein and fat in a non-milk diet. Very young infants push foods out with their tongue, but by between 6 and 9 months infants can receive and hold semi-solid food in their mouths more easily.

GUIDING PRINCIPLE 2. Continue frequent on-demand breastfeeding until 2 years of age or beyond

Breastfeeding should continue with complementary feeding up to 2 years of age or beyond, and it should be on demand, as often as the child wants.

Breast milk can provide one half or more of a child's energy needs between 6 and 12 months of age, and one third of energy needs and other high quality nutrients between 12 and 24 months (6). Breast milk continues to provide higher quality nutrients than complementary foods, and also protective factors. Breast milk is a critical source of energy and nutrients during illness (7), and reduces mortality among children who are malnourished (8, 9). In addition, as discussed in Session 1, breastfeeding reduces the risk of a number of acute and chronic diseases. Children tend to breastfeed less often when complementary foods are introduced, so breastfeeding needs to be actively encouraged to sustain breast-milk intake.

GUIDING PRINCIPLE 3. Practise responsive feeding applying the principles of psychosocial care

Optimal complementary feeding depends not only on what is fed but also on how, when, where and by whom a child is fed (10,11). Behavioural studies have revealed that a casual style of feeding predominates in some populations. Young children are left to feed themselves, and encouragement to eat is rarely observed. In such settings, a more active style of feeding can improve dietary intake. The term “responsive feeding” (see Box 2) is used to describe caregiving that applies the principles of psychosocial care.

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Box 2

Responsive feeding. Feed infants directly and assist older children when they feed themselves. Feed slowly and patiently, and encourage children to eat, but do not force them. If children refuse many foods, experiment with different food combinations, (more...)

A child should have his or her own plate or bowl so that the caregiver knows if the child is getting enough food. A utensil such as a spoon, or just a clean hand, may be used to feed a child, depending on the culture. The utensil needs to be appropriate for the child's age. Many communities use a small spoon when a child starts taking solids. Later a larger spoon or a fork may be used.

Whether breastfeeds or complementary foods are given first at any meal has not been shown to matter. A mother can decide according to her convenience, and the child's demands.

GUIDING PRINCIPLE 4. Practise good hygiene and proper food handling

Microbial contamination of complementary foods is a major cause of diarrhoeal disease, which is particularly common in children 6 to 12 months old (12). Safe preparation and storage of complementary foods can prevent contamination and reduce the risk of diarrhoea. The use of bottles with teats to feed liquids is more likely to result in transmission of infection than the use of cups, and should be avoided (13).

All utensils, such as cups, bowls and spoons, used for an infant or young child's food should be washed thoroughly. Eating by hand is common in many cultures, and children may be given solid pieces of food to hold and chew on, sometimes called “finger foods”. It is important for both the caregiver's and the child's hands to be washed thoroughly before eating.

Bacteria multiply rapidly in hot weather, and more slowly if food is refrigerated. Larger numbers of bacteria produced in hot weather increase the risk of illness (14). When food cannot be refrigerated it should be eaten soon after it has been prepared (no more than 2 hours), before bacteria have time to multiply.

Basic recommendations for the preparation of safe foods (15) are summarized in Box 3.

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Box 3

Five keys to safer food. Keep clean Separate raw and cooked

GUIDING PRINCIPLE 5. Start at 6 months of age with small amounts of food and increase the quantity as the child gets older, while maintaining frequent breastfeeding

The overall quantity of food is usually measured for convenience according to the amount of energy – that is, the number of kilocalories (kcal) – that a child needs. Other nutrients are equally important, and are either part of, or must be added to, the staple food.

Figure 10 shows the energy needs of infants and young children up to 2 years of age, and how much can be provided by breast milk. It shows that breast milk covers all needs up to 6 months, but after 6 months there is an energy gap that needs to be covered by complementary foods. The energy needed in addition to breast milk is about 200 kcal per day in infants 6–8 months, 300 kcal per day in infants 9–11 months, and 550 kcal per day in children 12–23 months of age. The amount of food required to cover the gap increases as the child gets older, and as the intake of breast milk decreases (16).

FIGURE 10. Energy required by age and the amount from breast milk.


Energy required by age and the amount from breast milk.

Table 1 summarizes the amount of food required at different ages,1 the average number of kilocalories that a breastfed infant or young child needs from complementary foods at different ages, and the approximate quantity of food that will provide this amount of energy per day. The quantity increases gradually month by month, as the child grows and develops, and the table shows the average for each age range.

TABLE 1. Practical guidance on the quality, frequency and amount of food to offer children 6–23 months of age who are breastfed on demand.


Practical guidance on the quality, frequency and amount of food to offer children 6–23 months of age who are breastfed on demand.

The actual amount (weight or volume) of food required depends on the energy density of the food offered. This means the number of kilocalories per ml, or per gram. Breast milk contains about 0.7 kcal per ml. Complementary foods are more variable, and usually contain between 0.6 and 1.0 kcal per gram. Foods that are watery and dilute may contain only about 0.3 kcal per gram. For complementary foods to have 1.0 kcal per gram, it is necessary for them to be quite thick and to contain fat or oil, which are the most energy-rich foods.

Complementary foods should have a greater energy density than breast milk, that is, at least 0.8 kcal per gram. The quantities of food recommended in Table 1 assume that the complementary food will contain 0.8–1.0 kcal per gram. If a complementary food is more energy dense, then a smaller amount is needed to cover the energy gap. A complementary food that is more energy-dilute needs a larger volume to cover the energy gap.

When complementary food is introduced, a child tends to breastfeed less often, and his or her intake of breast milk decreases (17), so the food effectively displaces breast milk. If complementary food is more energy diluted than breast milk, the child's total energy intake may be less than it was with exclusive breastfeeding, an important cause of malnutrition.

A young child's appetite usually serves as a guide to the amount of food that should be offered. However, illness and malnutrition reduce appetite, so that a sick child may take less than he or she needs. A child recovering from illness or malnutrition may require extra assistance with feeding to ensure adequate intake. If the child's appetite increases with recovery, then extra food should be offered.

GUIDING PRINCIPLE 6. Gradually increase food consistency and variety as the infant grows older, adapting to the infant's requirements and abilities

The most suitable consistency for an infant's or young child's food depends on age and neuromuscular development (19). Beginning at 6 months, an infant can eat pureed, mashed or semi-solid foods. By 8 months most infants can also eat finger foods. By 12 months, most children can eat the same types of foods as consumed by the rest of the family. However, they need nutrient-rich food, as explained in Guiding principle 8, and foods that can cause choking, such as whole peanuts, should be avoided.

A complementary food should be thick enough so that it stays on a spoon and does not drip off. Generally, foods that are thicker or more solid are more energy- and nutrient-dense than thin, watery or soft foods. When a child eats thick, solid foods, it is easier to give more kcal and to include a variety of nutrient-rich ingredients including animal-source foods. There is evidence of a critical window for introducing ‘lumpy’ foods: if these are delayed beyond 10 months of age, it may increase the risk of feeding difficulties later on. Although it may save time to continue feeding semi-solid foods, for optimal child development it is important to gradually increase the solidity of food with age.

GUIDING PRINCIPLE 7. Increase the number of times that the child is fed complementary foods as the child gets older

As a child gets older and needs a larger total quantity of food each day, the food needs to be divided into a larger number of meals.

The number of meals that an infant or young child needs in a day depends on:

  • how much energy the child needs to cover the energy gap. The more food a child needs each day, the more meals are needed to ensure that he or she gets enough.
  • the amount that a child can eat at one meal. This depends on the capacity or size of the child's stomach, which is usually 30 ml per kg of the child's body weight. A child who weighs 8 kg will have a stomach capacity of 240 ml, about one large cupful, and cannot be expected to eat more than that at one meal.
  • the energy density of the food offered. The energy density of complementary foods should be more than breast milk, that is, at least 0.8 kcal per gram. If the energy density of food is lower, a larger volume of food is needed to fill the gap, which may need to be divided into more meals.

As shown in Table 1, a breastfed infant 6-8 months old needs 2–3 meals a day, and a breastfed infant 9–23 months needs 3–4 meals a day. Depending on the child's appetite, 1–2 nutritious snacks may be offered. Snacks are defined as foods eaten between meals, often self-fed finger foods, which are convenient and easy to prepare. If they are fried, they may have a high energy density. The transition from 2 to 3 meals, and from smaller to larger meals, happens gradually between those ages, depending on the child's appetite and how he or she is developing.

If a child eats too few meals, then he or she will not receive enough food to cover energy needs. If a child eats too many meals, he or she may breastfeed less, or may even stop breastfeeding altogether. In the first year of life, displacement of breast milk may reduce the quality and amount of the child's total nutrient intake.

GUIDING PRINCIPLE 8. Feed a variety of nutrient-rich foods to ensure that all nutrient needs are met

Complementary foods should provide sufficient energy, protein and micronutrients to cover a child's energy and nutrient gaps, so that together with breast milk, they meet all his or her needs.

Figure 11 shows the energy, protein, iron and vitamin A gaps that need to be filled by complementary foods for a breastfed child 12–23 months of age. The light part of each bar shows the percentage of the child's daily needs that can be provided by an average intake of 550 ml of breast milk. The dark part of the bar shows the gap that needs to be filled by complementary foods.

FIGURE 11. Gaps to be filled by complementary foods for a breastfed child 12–23 months.


Gaps to be filled by complementary foods for a breastfed child 12–23 months.

The largest gap is for iron, so it is especially important that complementary foods contain iron, if possible from animal-source foods such as meat, organs, poultry or fish. Pulses (peas, beans, lentils, nuts) fed with vitamin C-rich foods to aid absorption provide an alternative, but they cannot replace animal-source foods completely.

Box 4 summarizes characteristics of good complementary foods.

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Box 4

Good complementary foods are. Rich in energy, protein and micronutrients (particularly iron, zinc, calcium, vitamin A, vitamin C and folate); Not spicy or salty;

The basic ingredient of complementary foods is usually the local staple. Staples are cereals, roots and starchy fruits that consist mainly of carbohydrate and provide energy. Cereals also contain some protein; but roots such as cassava and sweet potato, and starchy fruits such as banana and breadfruit, contain very little protein.

A variety of other foods should be added to the staple every day to provide other nutrients. These include:

  • Foods from animals or fish are good sources of protein, iron and zinc. Liver also provides vitamin A and folate. Egg yolk is a good source of protein and vitamin A, but not of iron. A child needs the solid part of these foods, not just the watery sauce.
  • Dairy products, such as milk, cheese and yoghurt, are useful sources of calcium, protein, energy and B vitamins.
  • Pulses – peas, beans, lentils, peanuts, and soybeans are good sources of protein, and some iron. Eating sources of vitamin C (for example, tomatoes, citrus and other fruits, and green leafy vegetables) at the same time helps iron absorption.
  • Orange-coloured fruits and vegetables such as carrot, pumpkin, mango and papaya, and dark-green leaves such as spinach, are rich in carotene, from which vitamin A is made, and also vitamin C.
  • Fats and oils are concentrated sources of energy, and of certain essential fats that children need to grow.

Vegetarian (plant-based) complementary foods do not by themselves provide enough iron and zinc to meet all the needs of an infant or young child aged 6–23 months. Animal-source foods that contain enough iron and zinc are needed in addition. Alternatively, fortified foods or micronutrient supplements can fill some of the critical nutrient gaps.

Fats, including oils, are important because they increase the energy density of foods, and make them taste better. Fat also helps the absorption of vitamin A and other fat-soluble vitamins. Some fats, especially soy and rapeseed oil, also provide essential fatty acids. Fat should comprise 30–45% of the total energy provided by breast milk and complementary foods together. Fat should not provide more than this proportion, or the child will not eat enough of the foods that contain protein and other important nutrients, such as iron and zinc.

Sugar is a concentrated source of energy, but it has no other nutrients. It can damage children's teeth, and lead to overweight and obesity. Sugar and sugary drinks, such as soda, should be avoided because they decrease the child's appetite for more nutritious foods. Tea and coffee contain compounds that can interfere with iron absorption and are not recommended for young children.

Concerns about potential allergic effects are a common reason for families to restrict certain foods in the diets of infants and young children. However, there are no controlled studies that show that restrictive diets have an allergy-preventing effect. Therefore, young children can consume a variety of foods from the age of six months, including cow milk, eggs, peanuts, fish and shellfish (18).

GUIDING PRINCIPLE 9. Use fortified complementary foods or vitamin-mineral supplements for the infant as needed

Unfortified complementary foods that are predominantly plant-based generally provide insufficient amounts of certain key nutrients (particularly iron, zinc and vitamin B6) to meet recommended nutrient intakes during complementary feeding. Inclusion of animal-source foods can meet the gap in some cases, but this increases cost and may not be practical for the lowest-income groups. Furthermore, the amounts of animal-source foods that can feasibly be consumed by infants (e.g. at 6–12 months) are generally insufficient to meet the gap in iron. The difficulty in meeting the needs for these nutrients is not unique to developing countries. Average iron intakes in infants in industrialized countries would fall well short of recommended intake if iron-fortified products were not widely available. Therefore, in settings where little or no animal-source foods are available to many families, iron-fortified complementary foods or foods fortified at the point of consumption with a multinutrient powder or lipid-based nutrient supplement may be necessary.

GUIDING PRINCIPLE 10. Increase fluid intake during illness, including more frequent breastfeeding, and encourage the child to eat soft, favourite foods. After illness, give food more often than usual and encourage the child to eat more

During an illness, the need for fluid often increases, so a child should be offered and encouraged to take more, and breastfeeding on demand should continue. A child's appetite for food often decreases, while the desire to breastfeed increases, and breast milk may become the main source of both fluid and nutrients.

A child should also be encouraged to eat some complementary food to maintain nutrient intake and enhance recovery (20). Intake is usually better if the child is offered his or her favourite foods, and if the foods are soft and appetizing. The amount eaten at any one time is likely to be less than usual, so the caregiver may need to give more frequent, smaller meals.

When the infant or young child is recovering, and his or her appetite improves, the caregiver should offer an extra portion at each meal or add an extra meal or snack each day.

3.2. Recommendations for micronutrient supplementation

Micronutrients are essential for growth, development and prevention of illness in young children. As discussed earlier in Guiding principle 9, micronutrient supplementation can be an effective intervention in some situations. Recommendations are summarized below.

Vitamin A

WHO and UNICEF recommend universal supplementation with vitamin A as a priority in children aged 6–59 months in countries with a high risk of deficiency (Table 2). In these countries, a high dose of vitamin A should also be given to children with measles, diarrhoea, respiratory disease, chickenpox, other severe infections, or who live in the vicinity of children with vitamin A deficiency (21).

TABLE 2. High-dose universal distribution schedule for prevention of vitamin A deficiency.


High-dose universal distribution schedule for prevention of vitamin A deficiency.


As a rule, fortified foods should be preferred to iron supplements for children during the complementary feeding period. Caution should be exercised with iron supplementation in settings where the prevalence of malaria and other infectious diseases is high. In malaria-endemic areas, universal iron supplementation is not recommended. If iron supplements are used, they should not be given to children who have sufficient iron stores as the risks of severe adverse events appear to be greater in those children. Prevention and management of anaemia in such areas requires a screening system to identify iron-deficient children, and the availability of and accessibility to appropriate anti-malarial and other anti-infective treatments (22,23).


In 1994, WHO and UNICEF recommended universal salt iodization (USI) as a safe, cost-effective and sustainable strategy to ensure sufficient intake of iodine by all individuals. However, in areas with severe iodine deficiency, vulnerable groups – pregnant and lactating women and children less than 2 years – may not be adequately covered when USI is not fully implemented, and iodine supplementation may be necessary. The WHO/UNICEF Joint Statement on reaching optimal iodine nutrition in pregnant and lactating women and young children provides guidance for the categorization of countries and subsequent planning of an adequate response (24).


Zinc supplementation is recommended as adjunct therapy in the management of diarrhoea. Zinc (20 mg/day) should be given to all children with diarrhoea for 10–14 days. In infants below 6 months of age, the dose of zinc should be 10 mg/day (25).

3.3. Local adaptation of complementary feeding recommendations

Table 3 lists types of foods, the principle nutrients they contain, and how they can be fed to children for good complementary feeding. To develop specific feeding recommendations that respond to the Guiding principles and that are locally acceptable and affordable, a process of adaptation is needed. It is useful to involve caregivers and families in the process of adaptation, and of deciding what is culturally appropriate (26). The following steps are usually required:

TABLE 3. Appropriate foods for complementary feeding.


Appropriate foods for complementary feeding.

  • Review existing national or local feeding guidelines.
  • Develop a list of locally available foods.
  • Find out the nutrient content of the local foods from food tables (27).
  • Calculate the amount of various foods that would provide a child with his or her daily needs of the various nutrients – linear programming techniques can be used for this (28).
  • Assess which foods and quantities of foods caregivers and families accept as suitable for children, and identify their feeding practices and preferences.
  • Arrange trials of improved practices, asking mothers or other caregivers to choose new, improved feeding practices and try them out themselves. Obtain feedback on what works best in their circumstances.

Whether or not vitamin-mineral supplements should be included in the recommendations depends on the micronutrient content of locally-available foods, and whether children can eat enough suitable foods.


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The age ranges should be interpreted as follows: a child 6–8 months is 6 months or older (≥ 180 days) but is not yet 9 months old (< 270 days).

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