Infant Nutrition

Definition

Children between the ages of birth and one year are considered infants. Infants grow very rapidly and have special nutritional requirements that are different from other age groups.

Purpose

Infant nutrition is designed to meet the special needs of very young children and give them a healthy start in life. Children under one year old do not have fully mature organ systems. They need nutrition that is easy to digest and contains enough calories, vitamins, minerals, and other nutrients to grow and develop normally. Infants also need the proper amount of fluids for their immature kidney’s to process. In addition, infant nutrition involves avoiding exposing infants to substances that are harmful to their growth and development.

Description

Infancy is a time of incredibly rapid growth and development. Getting the right kinds of nutrients in the right quantities and avoiding the wrong kinds of substances gives infants the best chance at a healthy start to life. Parents are responsible for seeing that their infant’s nutritional needs are met. Infant nutrition is so important that the United States Department of Agriculture has developed the WIC program. This program provides free health and social service referrals, nutrition counseling, and vouchers for healthy foods to supplement the diet of pregnant and breastfeeding women, infants, and children up to age 5 who are low-income and nutritionally at risk. In 2004, WIC serve about 7.9 million people, including 2 million infants and 1.9 million pregnant and nursing women.

Breastfeeding

Human milk is uniquely suited to the nutrition needs of newborns. Many health organizations, including the American Academy of Pediatrics (AAP), the American Medical Association (AMA), the American Dietetic Association (ADA), and the World Health Organization (WHO) support the position that breast milk is the best and most complete form of nutrition for infants. The AAP recommends that infants should be exclusively breastfed for the first 6 months of life and that breastfeeding should continue for at least 12 months.
Breastfeeding in the United States slowly increased in acceptance in the last decade of the twentieth century. In 1998, 64% of American mothers breastfed their babies for a short time after birth. Only 29% were still breastfeeding by the time their baby was 6 months old. The United States Department of Health and Human Services developed a set of health goals for the nation to aim for by the year 2000. One of these goals involved breastfeeding. The Healthy People 2000 goal was for 75% of American women to breastfeed their babies for a period immediately after birth and 50% to breastfeed for the first 6 months of their infant’s life. Although there is significant variation in support for breastfeeding among different racial and ethnic groups in the United States, no racial group met this target. In 2000, the Department of Health and Human Services estimated that:
  • 45% of African American mothers breastfed their infants for a short time after birth; &19% were breastfeeding at 6 months; 9% at 12 months.
  • 66% of Hispanic mothers breastfed their infants for a short time after birth; 28% were breastfeeding at 6 months; 19% at 12 months.
Required nutrients for infant formula
NutrientMinimum(1) per 100 kilocaloriesMaximum(1) per 100 kilocalories
Protein (g)(2)1.84.5
Fat:
grams3.36.0
% calories30.054.0
Essential fatty acids (linoleate):
mg300.0
% calories2.7
Vitamins:
A (IU)(3)250.0 (75 mcg)750.0 (225 mc
D (IU)40.0100.0
K (mcg)4.0
E (IU)0.7 (with 0.7 IU/g linoleic acid)
C (ascorbic acid) (mg)8.0
B1 (thiamine) (mcg)40.0
B2 (riboflavin) (mcg)60.0
B6 (pyridoxine) (mcg)35.0 (with 15 mcg/g of protein in formula)
B12 (mcg)0.15
Niacin (mcg)250.0
Folic acid (mcg)4.0
Pantothenic acid (mcg)300.0
Biotin (mcg)(4)1.5
Choline (mg)(4)7.0
Inositol (mg)(4)4.0
Minerals:
Calcium (mg)(5)50.0
Phosphorus (mg)(5)25.0
Magnesium (mg)6.0
Iron (mg)0.15
Iodine (mcg)5.0
Zinc (mg)0.5
Copper (mcg)60.0
Manganese (mcg)5.0
Sodium (mcg)20.060.0
Potassium (mg)80.0200.0
Chloride (mg)55.0150.0
(1) Stated per 100 kilocalories (Kcal)
(2) The source of protein is at least nutritionally equivalent to casein
(3) Retinol equivalents
(4) Required to be included in this amount only in formulas that are not milk based
(5) Calcium to phosphorus ratio must be not less than 1.1 nor more than 2.0
(Illustration by GGS Information Services/Thomson Gale.)
  • 68% of white mothers breastfed their infants for a short time after birth; 31% were breastfeeding at 6 months; 17% at 12 months.
Healthy People 2010, the health goals set for Americans during the first decade of the twenty-first century, include eliminating the differences among racial groups in the rate of breastfeeding. The goal for 2010 is for 75% of all women to be breastfeeding shortly after birth, 50% to be breastfeeding at 6 months, and 25% to breastfeed for a full year.
ADVANTAGES OF BREASTFEEDING. Research comparing formula-fed and breastfed babies convincingly shows that both full-term and premature breastfed infants have certain advantages over formula fed infants. One of the most important advantages conferred by breast milk is an increased resistance to infection.
An infant is born with an immature immune system that does not become fully functional for about two years. Since immune system cells makes antibodies to fight infection, an incompletely developed immune system leaves the infant vulnerable to many bacterial and viral infections. However, the nursing mother has a fully developed immune system, and many of the antibodies and other components of her immune system pass into her breast milk. Nursing infants take in their mother’s antibodies along with the other nutrients in breast milk. These antibodies survive passage through the infant’s digestive system and are absorbed into the infant’s blood, where they help protect against infection. Well-designed studies have repeatedly documented the fact that breastfed babies have fewer ear infections, bouts of diarrhea, respiratory infections, and cases of meningitis than formula-fed babies. Overall, the death rate of breastfeed babies during the first year of life is lower than the death rate of formula-fed babies.
Another way that breastfeeding protects against infection is by keeping the infant from being exposed to waterborne contaminants. In developing countries, many water supplies are contaminated with bacteria and chemicals. Using this water to mix formula increases the exposure of the baby to these pathogens and toxins. Breastfed babies do not have to worry about being exposed to this type of contamination.
Another advantage of breastfeeding is that infants are unlikely to gain too much weight. Childhood obesity is a major concern in the United States. Since mothers are unable to measure how much breast milk their baby consumes, they are less likely to encourage overfeeding. Research suggests that breastfed babies have a lower risk of developing type 2 diabetes. Other research suggests that the rate of other chronic diseases such as asthma, celiac disease, inflammatory bowel disease, and various allergies appears to be lower in breastfed babies than in babies fed formula. Premature babies especially appear to benefit from reduced chronic disease as a result of breastfeeding.
Breastfeeding also provides benefits to the nursing mother. To start with, breastfeeding is more economical than buying formula, even taking into account the extra food—about 500 calories daily— that the mother needs to eat when she is nursing. Since

KEY TERMS

Antibodies—proteins produced by immune system cells that destroy or disable viruses or bacteria. Antibodies are generally specific to each species of virus or bacteria, so that antibodies against one type of virus will not affect another type.
celiac disease—a digestive disease that causes damage to the small intestine. It results from the ability to digest gluten found in wheat, rye, and barley.
Exclusive breastfeeding—All an infant’s nutrient and fluid needs are met from breast milk.
Meningitis—a serious infection of the membranes surrounding the brain.
Type 2 diabetes—sometime called adult-onset diabetes. This disease prevents the body from properly using glucose (sugar).
celiac disease—digestive disease that causes damage to the small intestine. It results from the ability to digest gluten found in wheat, rye, and barley.
breastfed babies on average get sick less than formula-fed babies, the family is also likely to save money on doctor visits, medicine, and time off from work to care for a sick child.
The mother’s health also benefits from breastfeeding. Nursing mothers tend to lose the weight they put on during pregnancy faster than mothers who do not nurse. The hormones that are released in the mother’s body when her infant nurses also help her uterus contract and become more nearly the size it was before pregnancy. Mothers who nurse their babies also seem to be less likely to develop breast, ovarian, or uterine cancer early in life. Finally, breastfeeding offers psychological benefits to the mother as she bonds with her baby and may reduce the chance of postpartum depression.
DISADVANTAGES OF BREASTFEEDING. Although breast milk is the best food for an infant, breastfeeding does cause some disadvantages to the mother. Initially babies breastfeed about every two to three hours. Some women find it exhausting to be available to the baby so frequently. Later, when the infant is older, the mother may need to pump breast milk for her child to eat while she is away or at work. Fathers sometimes feel shut out during the early weeks of breastfeeding because of the close bond between mother and child. In addition, women who are breast feeding must watch their diet carefully. Some foods or substances such ascaffeine can pass into breast milk and cause the baby to be restless and irritable. Finally, some women simply find the idea of breastfeeding messy and distasteful, and resent the fact that they need to be “on tap” much of the time. For women who cannot or do not want to breastfeed, infant formula provides an adequate alternative.

Formula feeding

Although infant formula is not as perfect a food as breast milk for infants (it is harder for them to digest and is not a chemical replica of human milk), formula does provide all the nutrients a baby needs to grow up healthy. The United States Food and Drug Administration (FDA) regulates infant formula under the Federal Food, Drug, and Cosmetic Act (FFDCA). The FDA sets the minimum amounts of 29 nutrients that must be present in infant formula and sets maximum amounts for 9 other nutrients. Some of these nutrients include Vitamins A, D, E, and K, and calcium. Some formulas contain iron, while others do not.
Substances used in infant formulas must be foods on the approved Generally Recognized as Safe (GRAS) list. Facilities for manufacturing infant formula are regularly inspected by the FDA, and the manufacturer must keep process and distribution records for each batch of formula. Every container of formula must show an expiration or use by date. The FDA must be informed of any changes made to the formula.
Infant formulas are either cow’s milk based or soy based. Infants who show signs of lactose-intolerance (colicky, restless, gassy, spitting up) usually do well on soy-based formula. Formula comes in three styles:
  • ready-to-feed. This is the easiest type of formula to use. It can be poured straight from the can into a bottle. It is also the most expensive form of formula.
  • Concentrated liquid. This needs to be mixed with an equal portion of water. Concentrated liquid is less expensive than ready-t0-feed.
  • Powder. This needs to be mixed with water. Advantages are that it is the least expensive formula and that it keeps longer than the liquid varieties. The main disadvantage is that it requires accurate measuring of powder and water.

Reasons to formula feed

Not every woman wants or is able to breastfeed. Aside from personal preference, here are some reasons why some women should formula feed.
  • They are adoptive parents.
  • They have HIV, active tuberculosis, or hepatitis C. These diseases can be passed on to their infants through breast milk.
  • They use street drugs or abuse prescription medicines. Many drugs pass into breast milk and can permanently damage a baby’s health.
  • They are taking chemotherapy drugs, certain mood stabilizers, migraine headache medications or other drugs that pass into breast milk and whose effect on the infant is negative or unknown.
  • They have alcoholism or are binge drinkers. The alcohol they drink will be present in breast milk.
  • They have difficult to control diabetes and may have increased difficulty controlling their blood sugar level if they choose to breastfeed.
  • They are going to be separated from their baby for significant periods.
  • They have had breast surgery that interferes with milk production.
  • They are emotionally repelled by the idea of breastfeeding.
  • A few babies are born with a genetic inborn error in metabolism that prevents them from digesting any mammalian milk. These babies must be fed soy-based formula in order to survive.

Pros and cons of formula feeding

Formula feeding has some definite advantages. Anyone, not just the mother, can feed the infant. This gives the mother more flexibility in her schedule and allows the father or other relatives to enjoy a special closeness with the baby that comes with feeding. Also, the mother does not need to be concerned about how her diet affects her baby and she does not need to worry about breast milk leakage. In addition, since formula is digested more slowly than breast milk, feedings are less frequent. Some women feel uncomfortable nursing in front of other people or find it difficult to locate places to nurse in private. Formula feeding eliminates this problem.
There are also disadvantages to formula feeding. Aside from the fact that formula is not an exact duplicate of breast milk and is harder to digest, it also costs more and requires more advance preparation. Bottles need to be washed, and the water used to mix formula, at least in the early months, needs to be boiled or be special bottle water suitable for infants. The Academy of General Dentistry warns that some public water supplies are fluoridated at levels too high for infants, and that fluorodosis of the primary (baby) teeth may result. Fluorodosis is a cosmetic problem. It causes brown spots on the teeth, but does not weaken them in any way. Finally, formula must be refrigerated once it is mixed or a can is opened. It can only be kept about 2 days in the refrigerator, so is there is more likely to be waste. Likewise, when traveling, bottles need to be refrigerated. Although most babies do not mind cold formula, many parent like to heat their child’s bottle to body temperature, another inconvenience when traveling.

Transitioning to solid foods

When an infant is between four and six months old, most pediatricians recommend introducing the infant to solid food. By this age, infants begin to have the muscle coordination to swallow runny solids. If there is a family history of food allergies, some pediatricians recommend waiting until 6 months or older to start solid food.
Normally solid feeding begins with a small amount of iron-fortified rice or other single-grain cereal mixed into a slurry the consistency of thin gravy with formula or breast milk. The infant is then offered a small amount of cereal on a small spoon. It may take many attempts before the infant is happy with the new food. After runny cereal is accepted, a thicker cereal can be offered. When the child eats this with ease, parents can begin feeding one new pureed food every week. Commercial baby food is available in jars or frozen. Baby food can also be made at home using a blender or food processor. Portions can be frozen in an ice cube tray and thawed as needed.
About the same time babies begin eating solid food, they are ready to take small sips of apple, grape, or pear juice (but not citrus juices) from a cup. Juice should not be served in a bottle. By the end of the first year, infants can eat a variety of ground or chopped soft foods that the rest of the family eats.

Foods that should not be fed to infants

Some foods are not appropriate for children during their first year. These include:
  • homemade formula. The nutrient requirements for infants are very specific and even a small excesses or deficits of a particular nutrient can permanently harm the child’s development.
  • cow’s milk. Plain cow’s milk should not be offered before 6 months, after this it can be introduced in small amounts as part of weaning foods but should not be offerd as the main drink before age 1. The cow’s milk in formula has been altered to make it acceptable for infants.
  • honey. Honey can contains spores of the bacterium Clostritium botulinum. This bacterium causes a serious, potentially fatal disease called infant botulism. Older children and adults are not affected. C. botulinumcan also be found in maple syrup, corn syrup, and undercooked foods.
  • well cooked eggs can be offered between 6-9 months (later if any family history of atopy), fish (can be offered from 6-9 months, shellfish, peanuts, and peanut butter. These often trigger an allergic reaction during the first year.
  • orange, grapefruit, or other citrus juices. These often cause a painful diaper rash during the first year.
  • home prepared spinach, collard greens, turnips, or beets. These may contain high levels of harmful nitrates from the soil. Jarred versions of these foods are okay.
  • raisins, whole grapes, hot dog rounds, hard candy, popcorn, raw carrots, nuts, and stringy meat. These and similar foods can cause choking, a major cause of accidental death in infants and toddlers.

Precautions

Mothers with certain health conditions such as those mentioned above should not breastfeed. Women with chronic diseases should discuss this with their healthcare provider.
Mothers using certain drugs should not breastfeed.
Parents using concentrated liquid and powdered formulas must measure and mix formula accurately. Inaccurate measuring can harm the infant’s growth and development. Water used in mixing formula must be free of pathogens, contaminants, and excessive levels offluoride.

Interactions

Street drugs, many prescription and over-the-counter drugs, and alcohol pass into breast milk and have the potential to permanently harm an infant’s growth and development. Before taking any drugs, a pregnant or breastfeeding woman should consult her healthcare provider. Caffeine also passes into breast milk. Some women find that even moderate amounts of coffee or caffeinated sodas cause their infant to become restless and irritable, while others find little effect. Breastfeeding women should monitor their caffeine intake and try to keep it to a minimum.

Complications

Many women have trouble getting the newborn to latch on and begin breastfeeding. This can usually be overcome with the help of a lactation consultant or pediatric nurse. Breastfeeding can cause the mother to develop sore, infected nipples. This is usually a temporary condition that should not be a reason to stop breastfeeding.
Complications from bottle feeding tend to be related to the infant’s difficulty in digesting formula. Some infants become gassy and colicky and may fuss, cry for long periods, and spit up cow’s milk-based formula. A switch to soy-based formula on the advice of a healthcare professional usually relieves this problem. Other complications of formula feeding are generally related to improper mixing of formula.

Parental concerns

Breastfeeding parents often are concerned about whether their baby is getting enough milk, since there is no way to directly measure how much milk a baby consumes when nursing. Newborns should have a minimum of 6-8 wet diapers and four bowel movements during the first two weeks of life. As the child grows, these numbers will gradually decrease. In addition, a woman’s breasts should feel hard and full (sometimes even painful) before nursing, and softer after nursing. Newborns nurse every 2–3 hours, but they should seem satisfied after nursing. The most definite sigh that the baby is getting enough food is that he or she is gaining weight.
Infants grow in irregular spurts. They may eat hungrily for a few days and then eat little few days later. Parents often worry about this, but it is a normal occurrence.
The transition to solid food is often a slow process. Infants eat very small amounts and often must be exposed to a new food multiple times before they will eat it willingly. Since childhood obesity is a major problem in the United States, parents and caregivers should avoid encouraging the infant to overeat.