Infant Nutrition

The first year of life is a period of very rapid growth. An infant's birth weight doubles after about five months and triples by the first birthday, by which time the infant's length increases by half. Adequate and appropriate nutrition is essential during this period, for infants that do not receive sufficient calories , vitamins , and minerals will not reach their expected growth.

Nutrient Requirements

An infant's requirement for calories is determined by size, rate of growth, activity, and energy needed for metabolic activities. Calorie needs per pound of body weight are higher during the first year of life than at any other time. Since there is variation among infants, a range of recommended calorie intakes have been developed. For the first four to six months of life, breast or formula feeding can provide sufficient calories. Measuring weight and length, and plotting it on a standardized growth grid, can determine the adequacy of an infant's calorie intake.

The calories in an infant's diet are provided by protein , fat , and carbohydrates . Protein is a basic part of every cell. Of the protein requirement, 50 percent is used for growth in the first two months of life, a figure that declines to 11 percent by two to three years of age. Fat provides 40 to 50 percent of the calories supplied during infancy and is a source of essential fatty acids . Carbohydrates, primarily lactose, are the principal source of dietary energy. Water requirements for the first six months are met when adequate amounts of breast milk or infant formula are consumed.

Breast milk from a well-nourished mother will supply adequate amounts of most vitamins and minerals, as will an iron - fortified formula. Vitamin D is also recommended for the breastfed infant, particularly infants who live in northern urban areas who are dark-skinned, who are kept covered due to cultural practices, or whose mothers have an inadequate intake of vitamin D. In places where the water supply is severely low in fluoride (less than 3 parts per million), fluoride supplementation might be considered for breastfed infants over six months of age.

Breastfeeding

All professional and international health organizations are in agreement that breastfeeding is the recommended method of infant feeding. Although breastfeeding is clearly essential for infants born in less industrialized countries, benefits are substantial in industrialized countries as well. In less industrialized countries, breastfeeding reduces infant mortality and morbidity .

Breast milk is nutritionally superior to formula, and it contains antibodies that reduce the risk of infection for the newborn baby. Breastfed infants have a decreased incidence of respiratory, gastrointestinal , and ear infections. The cost of feeding the infant is reduced, and the very nature of breastfeeding supports the mother-infant bond. There is also evidence that breastfed infants develop fewer allergies , and when tested at eighteen months of age they score higher on intelligence tests.

It is not advisable for an infant to receive whole cow's milk before one year of age. Feeding cow's milk before one year has been associated with the development of iron deficiency. If breastfeeding is discontinued before one year of age, an iron-fortified, commercially prepared infant formula is recommended.

Formula Feeding

The governments of most countries have developed nutrient standards for commercial infant formulas. These guidelines ensure that a formula has nutrients similar to the breast milk from a well-nourished woman. Most infant formulas are made from either modified cow's milk or soy, and both types will meet an infant's nutritional requirements . Standard infant formula comes in both a low-iron and iron-fortified form. Iron-fortified formula is always recommended, except in very specific circumstances. A third category of formulas has been developed for children with severe allergies, gastrointestinal problems, or other medical complications. These are classified as elemental formulas, and are prescribed when an infant cannot tolerate any other type of formula.

The newborn infant will feed between eight to twelve times a day. As weight is gained, the infant will take more at each feeding and the number of feedings per day will decrease. An infant who is receiving adequate feeds will have at least six wet diapers a day, will appear satisfied after a feeding, and will follow the established growth curve.

In less industrialized countries, or in situations where formula costs are too high, infant formulas made from evaporated milk have been used. This is not recommended, however, since an infant would require more vitamin and mineral supplementation, and there is also a risk of incorrectly prepared formula. When any type of formula is prepared, it is essential that the water, bottles, and all the equipment used are sanitized, that hands are washed during preparation, and that the formula is kept refrigerated.

Beikost (Solid Food)

An infant is physically ready for semi-solid foods between four to six months of age. Before this age the reflex that allows babies to suckle will push foods out of the mouth. At around six months infants begin to sit independently, draw in their lower lip as a spoon is removed from the mouth, and they can indicate hunger by opening the mouth—and refusal by closing the mouth and turning away. Some parents believe that solid foods help a baby sleep through the night. However, sleeping through the night is not related to food, but is a developmental milestone that occurs between one to three months of age. To eat solid foods at an early age might reduce an infant's intake of breast milk or formula, which could have a negative impact on nutritional status.

All solid foods should be offered by spoon, not put in a bottle. A new food might initially be rejected, but with repeated offerings acceptance increases. Baby rice cereal is often recommended as the first food for an infant, since it rarely provokes allergic reactions and is iron fortified. The cereal should be mixed with breast milk or formula until it has a semi-liquid consistency. The next foods offered can be single strained fruits, strained vegetables, and at seven to eight months, strained meats. New foods are added one at a time, for two to three days, while the infant is watched for a negative reaction. Reactions would include rashes, vomiting, or diarrhea. Commercially prepared baby foods are convenient, and the first-stage foods are prepared without added sugar and starches. Home-prepared baby foods can be more economical, however.

The American Dental Association recommends juice be given to an infant with a cup rather than a bottle. This decreases the risk of both baby bottle tooth decay and overfeeding. Baby bottle tooth decay, also known as nursing bottle mouth syndrome, is a disorder of extreme dental decay of the upper teeth, caused by infants or toddlers falling asleep while sucking a bottle filled with juice, milk, or any other fermentable liquid.

Self-Feeding

Self-feeding begins when an infant is able to sit up straight, grasp food with the hands or fingertips, and move the food from the hands to the mouth. This usually develops between six to seven months of age. Suitable foods are arrowroot biscuits, teething biscuits, and small pieces of soft fruit or soft cooked vegetables. To prevent choking when an infant is self-feeding, an adult caretaker should always be present.

Between seven and eight months, infants are able to move their shoulders and arms while seated. A more mature up-and-down chewing pattern is developing at this time, making it an appropriate time to begin introducing soft, mashed table foods. Well-cooked vegetables and meats and soft mashed fruits are usually well tolerated. Between ten and twelve months of age infants are becoming more aware of what others are eating, and they will want to imitate other people's eating habits. At this age it is appropriate to offer soft, chopped table foods in a meal pattern similar to the rest of the family. The one year old begins to clumsily self-feed with a spoon and sip from a cup. All these self-feeding skills will be continually refined during the toddler years.

Infancy is a time of tremendous growth that can be best met through breastfeeding. If this is not possible, commercial, iron-fortified infant formulas will provide adequate nutrition. Semi-solid foods are added to prepare the infant for more mature chewing and feeding. Throughout the first year it is important for parents to learn to recognize and accept an infant's cues regarding their feelings of hunger and fullness. Responsiveness to an infant's appetite will prevent overfeeding. Observing an infant's readiness to chew, and providing appropriate foods, will help them develop self-feeding skills and independent eating.

SEE ALSO Baby Bottle Tooth Decay ; Beikost ; Breastfeeding .

Sheah Rarback

Bibliography

American Dietetic Association (1997). "Promotion of Breastfeeding." Journal of the American Dietetic Association 97:662–666.

Duyff, Roberta L. (1996). The American Dietetic Association's Complete Food and Nutrition Guide. Minneapolis, MN: Chronimed.

Fomon, Samuel J. (2001). "Feeding Normal Infants: Rationale for Recommendations." Journal of the American Dietetic Association 101:1002–1005.

Mitchell, Mary K. (1997). Nutrition across the Life Span. New York: W. B. Saunders.

Pipes, Peggy L., and Trahms, Cristine M. (1993). Nutrition in Infancy and Childhood . St. Louis, MO: Mosby.

Queen Samour, Patricia M.; King Helm, Kathy; and Lang, Carol E. (1993). Handbook of Pediatric Nutrition, 2nd edition. Gaithersburg: MD: Aspen.

Roberts, Susan B.; Heyman, Dennis M.; and Tracy, Lisa (1999). Feeding Your Child for Lifelong Health: Birth through Age Six. New York: Bantam.

Satter, Ellyn (2000). Child of Mine: Feeding with Love and Good Sense. Palo Alto, CA: Bull Publishing.

Williamson, Carol P., ed. (1998). Pediatric Manual of Clinical Dietetics. Chicago: American Dietetic Association.

Internet Resources

Baby Center. "Baby Food Basics." Available from <http://www.babycenter.com>

Queens University. "A Guide to Infant Feeding—From Birth to 24 Months." Available from <http://www.queensu.ca/medicine>