• Introduction
• Physical factors
• Nutrient needs
• Dietary choices
• References

Introduction

Anyone who spends any time with babies recognizes that they grow and change almost before your eyes. In the span of 12 months, most infants learn to sit up, cut many teeth, start to crawl, move from crawling to walking, begin to communicate verbally, and triple their body weight. At no other time in the child's life, will he/she again experience such rapid growth and development. Good nutrition is the key to ensuring that growth and development proceeds optimally. Infants require all the essential vitamins and minerals and also need adequate amounts of calories and protein. If moms are able, exclusive breastfeeding is the preferred source of nutrition for the first six months of a baby's life. As the baby develops the physical skills necessary to eat solid foods, simple and hypoallergenic foods can be introduced slowly and continued breastfeeding can fill in any nutritional gaps.

Physical Factors

Infancy is characterized by extremely rapid physical growth and development. During the first few days of life, most infants lose a little bit of weight. But, within 7 to 10 days, they typically regain their birth weight and set off at a pace of growth that, on average, more than doubles their initial birth weight in four to six months and triples it within the first year of life! At the same time, the individual organ systems of the infant are developing to allow for increasingly more complex functions. To ensure that this growth and development proceeds optimally, infants need to obtain adequate amounts and high-quality forms of protein, essential fatty acids, vitamins, minerals, and other nutrients.

Nutrient Needs

Energy and Macronutrient Overview

Like all human beings at all stages of life, infants need adequate calories to support rapid growth and development and a healthy supply of macronutrients—including proteins, carbohydrates, and fats—to thrive during this critical period. A healthy supply means the right amount, because over-consumption and excess intake of macronutrients can be just as problematic for infants as under-consumption and deficiency. Quality is also very important, and sometimes overlooked, in the feeding of infants and children. During the first year of life, breastfeeding is usually the best path of nourishment for an infant, with very few supplemental foods needed (or none at all) to provide a healthy supply of macronutrients. This period of breastfeeding also places a unique emphasis on the mother's diet. The quality of a mother's milk depends in great part upon the mother's diet, not only with respect to macronutrients, but also to vitamins, minerals, phytonutrients, and potentially problematic food components. Allergic reactions in a nursing infant, for example, can often be improved by changes in the mother's diet. Several aspects of macronutrient quality are worth a special look during this period of development.

Caloric Intake

In 2002, the Institute of Medicine of the National Academies set a dietary reference intake (DRI) daily calorie range for infants from birth to six months of 520 to 570 calories, and 676 to 743 calories for infants between six and twelve months of age, depending on gender. If caregivers are sensitive to their infant's innate satiety signals, infants will naturally adjust their intake to meet their own energy needs. This is the perfect time to cultivate your baby's ability to self-regulate by honoring his/her hunger and satiety cues. Formula-fed infants typically consume more calories and experience greater weight gain than breast-fed infants. In fact, breastfeeding is associated with a 30% decrease in adolescent and adult obesity. When solid foods are introduced, quality, quantity and timing are all important factors. One study suggests that babies who were introduced to whole foods (vegetables and fruit as well as cooked meats and fish and home-prepared meals) had healthier body composition than infants fed store-bought, prepared baby food. In another study, introducing solid foods to formula-fed infants before four months was associated with a six-fold increase in the odds of obesity at age three. No association was found in breastfed infants. The best advice for getting your baby's energy needs met is to pay attention to hunger and satiety cues, monitor growth and weight gain, and feed your baby nutrient-rich whole foods when he/she takes an interest in eating solid foods.

Protein and Carbohydrates

Protein is essential for infants' tissue replacement and growth. As such, protein requirements are higher per kilogram of weight than for older children and adults. During the first year of life, the DRI for daily protein intake ranges between 9 and 13 grams per day. Breast milk or formula will be the primary source of protein in the first six months of life and then can be supplemented with high-quality food sources of protein such as fish, yogurt, pureed meat, and eggs. Carbohydrates are the primary source of fuel for infants and, if sufficient amounts are not provided, growth may be stunted because protein will be used to meet the energy needs. When introducing solid foods, focus on foods with complex carbohydrates such as mashed or pureed vegetables, fruit, and whole grain cereal.

Fats and Fatty Acid Quality

Fats supply infants with energy for their liver, brain, and heart. The current recommendation for infants younger than age one is to consume a minimum of 30 grams of fat per day. This amount is easily provided in the milk produced by a healthy mom and consumed by a regularly breastfeeding infant.

The quality and type of fat consumed during infancy is also important. The DRI recommendations include a suggested daily intake of at least 4.5 grams of the omega-6 essential fatty acid linoleic acid. This amount can often be provided in human milk without special careful attention to the diet on the part of a nursing mom. However, the DRI recommendation of one-half gram intake of linolenic acid—an omega-3 fatty acid—may not be as easily met by a nursing mom without more careful attention to her personal meal plan.

The omega-3 fatty acid known as DHA (docosahexaeonic acid) plays a critical role in neurological development and visual acuity. Evidence from several types of studies suggest that changes in brain concentrations of DHA are associated with changes in cognitive and behavioral performance in infants and toddlers. Studies on maternal DHA intake provide evidence that moms who consume more fish have higher breast milk concentrations of DHA. In 2008, a team of 19 international experts developed recommendations based on research on infant development and fatty acids and concluded that DHA should be added to infant formula. As a result, most infant formulas are now fortified with DHA. The guidelines also recommend that pregnant or breastfeeding women should include enough DHA in their personal diets to support the brain and eye development of their babies. More recent studies have been inconclusive with respect to the efficacy of DHA-fortified infant formula and the effect on cognitive development. While more research is needed, the weight of the evidence still suggests omega-3 fats play a critical role in early infant development. With that in mind, it makes sense for nursing mothers to include at least one source of omega-3 fats in their diet every day, in a serving size that provides closer to 1-2 grams of omega-3s. This amount can be found in 2-4 ounces of salmon or halibut, 5-10 walnut halves, or 2-4 teaspoons of ground flaxseeds. Mothers who are unable to or choose not to breastfeed should select an infant formula that contains omega-3 essential fatty acids.

Micronutrient Overview

When it comes to vitamins and minerals, it is the quality of the breastfeeding mom's diet that is extremely important. In the case of formula-fed infants and older children consuming solid foods, it's the quality of the formula and the foods that is important. There are many high-quality infant formulas on the market that contain all of the essential nutrients that babies need for normal growth and development. However, in almost all cases, the best bet for optimal nourishment of infants is breastfeeding by a mother whose diet is filled with a balanced mix of whole, natural foods like those we feature on the World's Healthiest Foods website. With that said, there are some nutritional deficiencies that are more common in infants and young children, most notably vitamin D. In 2008, the American Academy of Pediatrics doubled the recommended daily intake of vitamin D for infants and concluded that both breastfed and formula-fed infants could not receive adequate amounts of vitamin D without some form of supplementation. The recommendation is for babies to receive 400 IUs (10 mcg) of liquid vitamin D starting in the first few days after birth. Once solids are introduced, you can incorporate foods that are good sources of vitamin D, such as fish, eggs, and fortified foods and decrease supplementation. Sun exposure is another way to get vitamin D, but unprotected exposure for infants under six months is generally not recommended.

Source: Dietary Reference Intakes (DRIs): Recommended Dietary Allowances (RDAs) and Adequate Intakes (AIs), Food & Nutrition Board, Institute of Medicine, National Academy of Sciences (NAS), 1998 - 2010.

Dietary Choices

Naturally, newborns and infants have little control over what they eat, and their parents are responsible for selecting and providing any source of nourishment they receive. The clear ideal to shoot for, in virtually all circumstances, is breastfeeding. The composition of breast milk, even in mothers who are not optimally healthy, is still clearly superior to formula. The decision about whether and how long to breastfeed is complex for many mothers, and often involves issues related to physical challenges, employment outside the home, and lack of support for breastfeeding from the social and home environment. Moms who are unable or choose not to breastfeed can be assured that good-quality infant formulas are developed to closely mimic breast milk in their nutritional composition. While some studies show a possible advantage in cognitive development in breastfed infants, numerous studies show no developmental differences when comparing breastfed infants to formula-fed infants. There are, however, some studies that suggest incidences of obesity, asthma, otitis media (ear infections), and eczema may be lower in children who were breastfed for the first three to six months of life.

Infants who are bottle-fed are generally fed cow's milk-based formulas or soy-based formulas. There has been some concern about the safety of soy-based infant formulas due to the high levels of phytoestrogens that are naturally occurring in soy. One study noted that babies fed soy infant formula are exposed to a 6- to 11-fold higher level of isoflavones on a body weight basis than adults consuming soy as part of a balanced diet. The long-term physiological effects of these higher levels of isoflavones are still unknown, but a study that compared young adults who consumed cow's milk formula or soy milk formula found no statistical differences in 30 different outcomes that were measured. For those giving their infants formula, the American Academy of Pediatrics recommends erring on the side of caution and using cow's milk or hydrolyzed protein formulas as a first choice and soy formula only for infants who have a hereditary lactose deficiency or whose parents who choose vegetarianism.

Introducing Solids

The appropriate time to introduce solid foods is a controversial issue. Some nutritionists suggest introducing solid foods as early as four to six months after birth, while some suggest that the digestive and immune systems of infants are not developed sufficiently at this point to handle solid foods and argue that premature introduction of solid foods may lead to food allergies, poor digestion, and obesity. More recent research suggests that delaying certain food introductions, such as dairy, beyond six months may actually be associated with an increase in allergic symptoms such as eczema. So, how do you decide the best time to give your baby solid foods? To be safe, it is advisable to wait until your baby is at least six months of age. The American Academy of Pediatrics recommends breastfeeding as the sole source of nutrition for about six months, followed by a combination of breast milk and solid foods throughout the first year.

Your baby will start to give you signals that he/she is ready to start trying solid foods. At around five months, begin to watch for signs that your child is developing the physical skills necessary to begin eating. He/she should be able to sit up and should start to display chewing motions (up and down movement of the jaw). Select simple, unprocessed foods such as puréed cooked vegetables (yams, squash, and peas are great choices), fruit such as mashed bananas or applesauce, cooked whole grain cereals, and quality sources of protein such pureed fish, plain yogurt, or scrambled eggs. Once your baby cuts his/her first few teeth and develops the hand-eye coordination necessary to grasp and hold foods, you can begin to introduce a wider variety of foods. In addition to these physiological, growth-related benchmarks, many parents let their child's interest in solid foods help guide their decision about when to try them. Whenever possible, provide your infant with certified organic foods. These foods will help reduce exposure to unwanted pesticides and toxins.

Food Allergies

Sometimes an infant's dietary choices become affected by a condition called colic. This condition is characterized by inconsolable crying for several hours, often identified by the "rule of 3s" (crying for more than three hours a day, at least three days a week, for a period of three weeks or more). Food allergy has been identified as a common cause of colic. Consequently, a mother of a colicky breastfed infant may need to change her diet. Often, excluding dairy products can help. Formula-fed infants with colic may need a hypoallergenic or elemental formula. Colic is usually a temporary condition, but it can affect the infant's intake of food and should be addressed.

When introducing solid foods, it is a good idea to introduce new foods one at a time and wait two to three days in between to assess for any reactions such as diarrhea, vomiting, or skin issues. If your child has a reaction, it's often helpful to seek guidance from a registered dietitian to determine when to reintroduce potentially problematic foods and learn how to get nutrient needs met if certain foods need to be omitted.

References

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