HOW DO I MANAGE?
Complementary Feeding
Adequate nutrition during infancy and early childhood is essential to help child achieve his/ her genetic potential. Failure to introduce right foods at the right age not only has nutritional but also developmental consequences. Early nutritional deficits lead to impairments in intellectual performance, work capacity, reproductive outcomes and overall health during adolescence and adulthood. The cycle of malnutrition continues, as the malnourished girl child faces greater odds of giving birth to a malnourished, low birth weight infant when she grows up. That is why complementary feeding is often referred to as “safety net” that prevents young infants falling into trap of malnutrition during transition from breastfeeding to family-food. Yet another controversial aspect of introducing complementary feeds in the “right” manner is related to correlation between age of introduction of certain foods with allergies later in life. Despite such crucial importance, it is ironical that the research on complementary feeding has been accorded much less importance as compared to that on breastfeeding and vaccines. Due to limited evidence, there is a large variation (with lot of contradictions) in the recommendations regarding complementary feeding among various countries and even among different authorities within same country. In India, like everything else, the scenario is much more complex given the diverse socio-cultural practices associated with introduction of complementary feeding and transition to family food.
This article is a modest attempt to summarize the current best available evidence regarding the timing and nature of complementary feeding and further transition to family-food for Indian healthy, full-term infants.
When to start complementary feeds?
Till 2001, it was recommended that complementary foods should be introduced between 4-6 months of age. In 2000-01, the WHO commissioned a systematic review (1) of the available literature to address this issue. Mother and infant outcomes for babies that were exclusively breastfed for 6 months were compared with those who were exclusively breastfed for 3-4 months. It was found that there was no difference in the growth parameters in the two groups in either developing or developed country settings. Infants who continue exclusive breastfeeding for 6 months or more had significantly less risk of gastrointestinal tract infections, although there was no significant reduction in risk of atopic outcomes and respiratory tract infections. The data with respect to iron status was conflicting but suggest that, at least in developing-country settings, exclusive breastfeeding without iron supplementation through 6 months of age may compromise hematologic status. Based on this systematic review and expert consultation, World Health Assembly revised its recommendation that babies should be exclusively breastfed for 6 months followed by partial breastfeeding and complementary feeds after that. Many countries, including India (2) have adopted these recommendations. However, many countries and experts continue to support earlier recommendation of 4-6 months, since they believe that there is a risk of growth faltering and/or certain micronutrient deficiencies (like iron and zinc), at least in some babies, if initiation of complementary feeds is delayed to 6 months (3).
The ESPGHAN, in its 2008 guidelines (4), has recommended that exclusive or full breast-feeding for about 6 months is a desirable goal. However, infants should be managed individually so that insufficient growth or other adverse outcomes are not ignored and appropriate interventions are provided to them. Complementary feeding should not be introduced in any infant before 17 weeks, and should start in all the infants by 26 weeks.
In Indian context, longer duration of breastfeeding is very much desirable in view of following considerations:
1. Although we still need large, good quality studies to rule out modest differences in risk of undernutrition, the currently available data fails to demonstrate any statistically significant deficit in growth of infants that are exclusively breastfed for 6 months versus those in whom complementary feeds are started earlier (1, 5).
2. The data consistently shows that risk of infections, particularly gastrointestinal infections, is much less common in breastfed infants. The most recent Cochrane review (5), published in 2012, endorses this. This is particularly significant here in India due to high disease burden contributing to high infant mortality rate.
3. The 6th year Follow-Up (Y6FU) to the longitudinal study: Infant Feeding Practices Study II (IFPS-II), published in Pediatrics last month (6) has shown that babies that are predominantly breastfed in first 6 months of life have much lower odds of having sinus and ear infections at the age of 6 years! This has definitely thrown more weight in favour of longer duration of breastfeeding.
4. Critics argue that exclusive breastfeeding for 6 months may predispose some infants to certain micronutrient deficiencies like iron, zinc and certain vitamins, since the mothers of these infants might be deficient. However, for micronutrients like iron and zinc, adding complementary feeds might not be of much help in addressing the issue. Supplementing these infants with iron or zinc drops, while continuing breastfeeding is a much better solution (7). Similarly, certain vitamin deficiencies (like vitamin A, riboflavin, vitamin B6, and vitamin B12) might be corrected by giving appropriate supplements to mother and improving her diet rather than starting complementary feeds early (7).
5. This recommendation is also in line with the physiological and neurodevelopmental maturation of the infant. The data suggests that renal and gastrointestinal functions are sufficiently mature to metabolize complementary foods by about 4 months of age. By 5-6 months, their gums are also sufficiently firm to start chewing soft diet Neurodevelopmentally, by around 6 months, most infants can sit with support and can ‘‘sweep a spoon’’ with their upper lip rather than merely suck semisolid food off the spoon (4).
There is no controversy in the recommendation that complementary foods should never be started before 4 months of age, since the physiological studies have demonstrated that both renal function and gastrointestinal functions are not mature enough to metabolize nutrients from complementary foods (8). Moreover, too early introduction of complementary foods has been associated with increased odds of development of obesity (9, 10), allergy/ atopy (11), celiac disease (12) and type-1 diabetes mellitus (13, 14). Hence, complementary foods should neber be introduced prior to 4 months of age.
Milk feeds during complementary feeding period
It is desirable to continue breastfeeding even after the age of 6 months, while starting complementary foods. Breast-milk has better quality proteins, has higher fat content, better bioavailable micronutrients than most of the commonly used complementary foods. In addition, it provides numerous anti-infective properties that no other food item on earth can provide. Thus, continuing breastfeeding contributes significantly to growth and development of the young infant in addition to providing continued protection against infections. As the results of IFPS-II study (6) have shown, infants with longer duration of breastfeeding continue to enjoy the benefits in the long term too. Longer duration of breastfeeding is also linked to reduced risk of chronic childhood diseases (15, 16), obesity (16, 17) and improved cognitive outcomes (16, 18), although we still need larger longitudinal studies to confirm causal relationships of these associations. That’s why WHO and UNICEF recommend breastfeeding on demand until 2 years or beyond.
However, mothers who are unable to (e.g., working mothers), or would choose not to breastfeed also need be supported to optimize their infant’s nutrition. Human Milk Substitute (HMS), popularly known as formula milk or infant formula, is the milk of choice in such babies, as its composition is as per the human needs. With regards to unmodified cow’s milk, there are concerns regarding high potential renal solute load and low bioavailable iron content. There is some evidence that cow’s milk can provoke microscopic intestinal bleeding in infants, which further contributes to iron deficiency anemia (19, 20). Hence, ESPHAGN (4) and AAP (21) do not recommend introduction of cow’s milk as a main drink till the age of 12 months, although using small amount of cow’s milk to prepare complementary foods is considered as permissible. Many other developed nations (like Canada, Denmark and Sweden) recommend that it can be started after 9-10 months of age. However, more recent studies on occult blood loss suggest that in the older infants the losses are very minor and not likely to affect iron status significantly (22, 23). The gastrointestinal response to cow’s milk that causes blood loss decreases with age and disappears by 12 months (23). Furthermore, heat-treated cow’s milk does not provoke blood loss (24), so use of boiled or evaporated milk would eliminate this risk. Thus, the risk of iron deficiency provoked by occult blood loss appears to be low and can be further reduced by heat treatment or restrictions on the amount of milk consumed (25). Regarding high renal solute load, it is more problematic when the baby is only on milk feeds (i.e., in first 6 months of life). In older infants who are on mixed diet, extra renal solute load can be managed by giving extra fluids. This is especially important during the conditions of water loss, like diarrhea. If the child is on high-solute milk like animal milk, there is a significant risk of hypernatremic dehydration in the absence of adequate fluids during such illnesses.
In view of these findings, WHO in its 2005 guidelines (25) considers use of full-cream animal milk (cow, goat, buffalo, sheep, camel) as “acceptable” in infants older than 6 months of age, but recommends appropriate medicinal iron supplements and extra fluids in these infants and young children. Further extra fluids must be given during the period of illnesses to maintain good hydration. Skimmed milk is not recommended as it does not contain essential fatty acids, is deficient in fat-soluble vitamins and has a high potential renal solute load to energy ratio.
What food-items to start with?
Since rate of growth and metabolic rate are very high during the first two years of life, nutrient needs per unit body weight of infants and young children are very high. Since the stomach capacity at this age is small, hence they can’t consume large volume of food per meal. Hence, the nutrient density (amount of each nutrient per 100 kcal of food) of the diet needs to be very high. Thus, the first principle is to feed infants and young children with energy and nutrient dense foods. Addition of fat in every meal makes the food energy dense: Authorities recommend that 25% (ESPGHAN) to 45% (WHO) of total energy should be from fat (4, 25). In practical terms, in babies who do not eat animal-source foods daily, roughly10-20 g of added fats or oils are needed everyday unless a fat-rich food is given (such as foods or pastes made from groundnuts, other nuts and seeds). If animal-foods are eaten daily, then only about 5 g of additional fats or oils per day is needed (25).
Introduction of high-protein foods in complementary diet has been a topic of intense debate in last decade. Based on some observational studies it was suggested that delayed introduction of allergenic foods like eggs, fish, nuts, and seafood could help prevent atopy/ allergies later in life. In fact, American College of Allergy, Asthma, and Immunology released a consensus statement in 2006 that in at-risk infants the introduction of dairy products should be delayed until 12 months; eggs until 24 months; and peanuts, tree nuts, fish, and seafood until 3 years (26). However, this extreme position was questioned immediately by other experts (27). Since none of the studies could actually demonstrate reduction in incidence of allergies with such delayed introduction, currently the guidelines downplay the role of such restrictions (28, 29). In fact, some studies have shown that the risk of allergic sensitization is increased, if the introduction of allergenic foods is delayed (30-33). Palmer et al (34) recently published results of randomized control trial that demonstrated that early regular oral egg exposure in infants with eczema can reduce incidence of egg allergy by inducing immune tolerance pathways. On the other hand, the evidence continues to be strong that too early (before 4 months of age) introduction of complementary foods can increase the odds of allergies, atopy and asthma later in life. Hence, there is consensus globally that complementary foods should never be introduced before 4 months of age. Similarly, it has been demonstrated that too early (< 4 months) or too late (> 7 months) introduction of gluten in diet increases the odds of developing celiac disease (12); and just like allergies, continuation of breastfeeding while gluten is introduced around 6 months of age is protective against development of celiac disease (35).
Another consideration of avoiding animal-sourced foods like egg, fish and meat is the nutritional consequences of such a diet. Fish, for example is the best source of n-3 long chain polyunsaturated fatty acids (n-3 LCPUFA) and its reduced intake can affect cognitive outcome and immune function. Animal source foods also provide good-quality protein with balanced amino-acid composition. It has also been calculated that the requirements of iron and zinc can almost never be met in infants without daily intake of animal source foods other than milk products. Studies in Netherlands have shown that infants receiving a vegan or macrobiotic diet, with limited or no animal foods have significant deficiencies of energy, protein, vitamin B12, vitamin D, calcium, and riboflavin, and the infants had retarded growth, fat and muscle wasting, and slower psychomotor development. If the mother is following a vegan diet, is breast-feeding, and is not taking nutritional supplements, then there is a significant risk that the infant will experience severe cognitive impairment, and the risk is increased further if the infant continues on a diet containing no animal food (36). In a randomized trial of pureed meat versus iron-fortified cereal given to breast-fed infants as the first complementary food between 5 and 7 months, higher behavioral indices were reported at 12 months in the meat group, although the difference was not significant (37). Thus, WHO recommends that meat, poultry, fish or eggs should be eaten daily, or as often as possible (25) beginning at 6 months of age. The recommended amount is 50 g egg (1 egg/d) and 14-75 g/d of meat, fish or liver. If milk and other animal-source foods are not eaten in adequate amounts, both grains and legumes should be consumed daily, if possible within the same meal, to ensure adequate protein quality. These babies would also need medicinal supplements or other foods fortified with iron, zinc, and vitamin B-12 (25).
Consistency/ texture of the complementary foods also need to be taken care of, considering the infants’ nutritional needs and neurodevelopmental abilities. If the food offered is too thin, it would fill the infant’s stomach easily without fetching adequate nutrition. On the other hand, if it is inappropriately textured, the infant might be unable to consume more than a trivial amount, or may take so long to eat that food intake is compromised. Infants should be offered pureed, mashed and semi-solid foods beginning at 6 months. It should be thick enough to stay on the spoon without running off, when the spoon is tilted.
Breastfed babies get enough water, but non-breastfed babies need extra water. It has been calculated (38) that these babies need at least 400-600 mL/d of extra fluids (in addition to the 200-700 mL/d of water that is estimated to come from milk and other foods) in a temperate climate and 800-1200 mL/d in a hot climate. Thus, plain, clean (boiled, if necessary) water should be offered several times per day to ensure that the infant’s thirst is satisfied.
The food items that are not to be used as complementary foods are listed in Table -1. Table-1. Food items that should not be used as complementary foods
| S. No. | Food Item | Reason For Avoidance |
|---|---|---|
| 1. | Honey | Risk of infant botulism |
| 2. | Tea/ Coffee | Minimal nutrient value; interfere with absorption of iron |
| 3. | Sugary drinks like soft drinks | |
| 4. | Fruit juices | Decrease the child’s appetite for other foods, and may cause loose stools; also some studies have linked excess fruit juice consumption to failure to thrive, short stature and obesity |
| 5. | "Dal water" | Insignificant nutrient value; likely to “displace” more nutritious foods |
| 6. | Low-fat/ skimmed milk | It does not contain essential fatty acids, is deficient in fat-soluble vitamins and has a high potential renal solute load to energy ratio |
| 7. | Raw milk (i.e. not boiled or pasteurized) | Risk of disease transmission. |
| 8. | Condensed milk | Has high sugar content and a very high osmolarity |
| 9. | Milk “substitutes” (e.g. coffee creamer, soy milk) | They are not nutritionally equivalent to animal milk (although soy-based infant formulas are acceptable) |
| 10. | Junk and commercial foods, ready-made, processed food from the market, e.g. tinned foods/juices, cold-drinks, chocolates, biscuits, crisps, health drinks, bakery products, etc | Contribute little other than energy, and thereby decrease the child’s appetite for more nutritious food; excess consumption is linked to later development of obesity and other life-style disorders |
| 11. | Whole nuts, grapes, raw carrots or any other item that has a shape and/or consistency that may cause it to become lodged in the trachea | Choking hazard |
Increasing complementary foods and transition to family food
Infant’s nutritional needs, neurodevelopmental abilities and the socio-cultural issues need to be considered at every step during the transition. Parents must be encouraged to identify the staple homemade food comprising of cereal-pulse mixture (as these are fresh, clean and cheap) and make them caloric and nutrient rich as described above. They must be educated to be sensitive to baby’s hunger and satiety cues and feed accordingly. As the babies show interest in complementary feeds, the variety should be increased by adding new foods in the staple food one by one. Easily available, cost-effective seasonal uncooked fruits, green and other dark coloured vegetables, milk and milk products, pulses/legumes, animal foods, oil/butter, sugar/jaggery may be added in the staples gradually. Usually, a healthy breastfed infant would require 2-3 meals of complementary foods per day at 6-8 months of age and 3-4 times per day at 9-11 and 12-24 months of age (7). In addition, nutritious snacks (such as a piece of fruit or bread or chapatti with nut paste) offered 1-2 times per day, as desired. Snacks are defined as foods eaten between meals-usually self-fed, convenient and easy to prepare and should not be confused with things like chips, biscuits, etc. A non-breastfed baby would require more frequent meals and extra fluids.
Infants diet needs to be balanced, having food items from different “food groups”. The Infant and Young Child Feeding (IYCF) guidelines of IAP/ Government of India (2) recommend that the diet of 6-23 month olds should receive food from 4 or more food groups daily. The seven groups defined are: (i) Grains, roots and tubers, legumes and nuts; (ii) dairy products; (iii) flesh foods (meat fish, poultry); (iv) eggs, (v) vitamin A rich fruits and vegetables; (vi) other fruits and vegetables.
Another consideration in infant feeding is food consistency/ texture. The consistency of food needs to be increased gradually as the infant gets older, adapting to the infant’s requirements and abilities. By about 8 months of age, they are able to “munch” food (up and down mandibular movements) and they must be offered “finger foods” (snacks that can be eaten by them alone) also. By about 12 months of age, most infants are able to consume “family foods” of a solid consistency, although many are still offered semi-solid foods (presumably because they can ingest them more efficiently, and thus less time for feeding is required of the caregiver). There is suggestive evidence of a “critical window” for introducing “lumpy” solid foods: if these are delayed beyond 10 months of age, it may increase the risk of feeding difficulties later on (39). This is very common these days, possibly because of busy schedules (working parents) and market pressure of commercial cereal formulae. I have personally seen at least two children above 5 years of age who presented with chief complaint of inability to ingest anything that is not mixed in a “mixie”. The reason was failure to introduce textured food at the right time. Thus, although it may save time to continue feeding semi-solid foods, for optimal child development it is advisable to gradually increase food consistency with age.
Table-2 gives rough idea of amount, texture and frequency of complementary feeds at various ages. However, it is also important to note that we need not to be overly prescriptive about the amount of complementary foods to be consumed, recognizing that each child’s needs will vary due to differences in breast milk intake and variability in growth rate. Furthermore, children recovering from illness or living in environments where energy expenditure is high may require more energy than the average quantities.
| Age | Texture | Frequency | Average amount of each meal |
|---|---|---|---|
| 6-8 mo | Start with thick porridge, well mashed foods | 2-3 meals per day plus frequent Breastfeeding | Start with 2-3 tablespoonfuls |
| 9-11 mo | Finely chopped or mashed foods,and foods that baby can pick up | 3-4 meals plus breastfeed.Depending on appetite offer 1-2 snacks | ½ of a 250 ml cup/bowl |
| 12-23 mo | Family foods, chopped or mashed if necessary | 3-4 meals plus breastfeed.Depending on appetite offer 1-2 snacks | 3/4 to one 250 ml cup/bowl |
Last but not the least, there is increasing recognition that optimal infant feeding depends not only on what is fed, but also on how, when, where, and by whom the child is fed. It is recommended that infants and young children should be fed slowly and patiently, encouraging them to eat but avoiding force-feeding. Infants need to be fed directly, but as they grow, they should be encouraged to feed themselves, supervising and assisting them, as required. Most of these young children do not accept new foods readily, and need constant encouragement. With patience, experimenting with different food combinations, tastes, textures and methods of encouragement yields good results. The attention span is also less at this age. Parents need to minimize distractions at meal times. However, it must also be remembered that meal times are periods of learning and love – Talking to them with eye-t-eye contact and age-appropriate play provides useful psychosocial stimulation to the young one and goes a long way in early brain development (7, 25).
-Puneet Kumar, Kumar Child Care Clinic, New Delhi, kumarchildclinic@gmail.com
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