Vestergaard M, Obel C, Henriksen TB, Sorensen HT, Skajaa E, Ostergaard J. Duration of breastfeeding and developmental milestones during the latter half of infancy. Acta Paediatrica 88: 1327-1332, 1999.

Studies have suggested that breastfeeding may have a positive effect on long-term brain development. Researchers in Denmark studied 1'656 infants at the age of 8 months to determine whether breastfeeding affected mental development below the age of 1 year. Three developmental milestones were measured: crawling, pincer grip, and polysyllable babbling. Duration of breastfeeding was classified according to the number of months of exclusive breastfeeding. The results showed that 38.8% of the 7-month olds could babble in polysyllables. 93.7% of the mothers had exclusively breastfed their children for at least 1 month, with 65.7 % continuing until 4 months. The proportion of children who had mastered the milestones increased consistently with increased duration of exclusive breastfeeding. For example, 73.4% of babies who were exclusively breastfed for 6 months or more were polysyllable babblers versus 48.5 % of babies who had been exclusively breastfed for only 1 month. There was little or no confounding from various factors like family social status, mother's education, gestational age or mother's employment.

The authors believe that the causal relation between breastfeeding and brain development has major public health implications and should be explored further.

Smulevich VB, Solionova LG, Belyakova SV. Parental occupation and other factors and cancer risk in children: I. Study methodology and non-occupational factors, International Journal of Cancer 83: 712-717. 1999.

Increasingly, research is concentrating on the long term effects of infant feeding practices. A study carried out in Moscow was designed to determine whether both occupational and non-occupational factors were associated with childhood cancers. In this first part of the study factors other than occupational were analyzed with relation to the occurrence of childhood cancers.

Factors which did not show any association included smoking habits of the parents, parental alcohol consumption, and educational and socio-economic status of the parents. Factors which had some association with cancers included pathology during pregnancy, cancers in parents and grandparents, and duration of breastfeeding. When the duration of breastfeeding was not longer than 1 month the risk of all cancers, leukemias and non-Hodgkins' lymphoma were higher. There was a 7-fold increase for all cancers when the child was breastfed less than one month compared with those breastfed for 12 months or longer.

Chen CH, Wang TM, Chang HM, Chi CS. The effect of breast- and bottle-feeding on oxygen saturation and body temperature in preterm infants, Journal of Human Lactation 16(1): 21-27, 2000.

Authors of a study carried out in Taiwan explain that Eastern health workers believe that Chinese preterm infants need to bottle-feed for a long time because they are too fragile to breastfeed. In order to respond to this myth researchers compared the oxygen saturation, heart rate, respiratory rate and body temperature of 25 preterm infants during bottle- and breastfeeding. A comparison of breast and bottle- feeding of the same infant was made once the infant could latch on and feed effectively. The results showed that oxygen saturation and body temperature were significantly higher during breastfeeds than during bottle-feeds. Pulse and respiratory rates were also higher while breastfeeding. There were two episodes of apnea (breath pause longer than 20 seconds) and 20 episodes of oxygen desaturation (PaO2<90%) during bottle-feeding, but not during breastfeeding.

The authors conclude that "for Eastern preterm infants, breastfeeding is a more physiologically beneficial feeding method... and that culture, race and preterm delivery should not be an excuse for post-poning breastfeeding".

Fomon SJ, Ekstrand J. Fluoride intake by infants, Journal of Public Health Dentistry 59: 229-234, 1999.

Too high an intake of fluoride in infancy is associated with fluorosis of the secondary teeth. This problem can be of major importance in communities with low breastfeeding rates and fluoridized local water supply. Researchers in the USA analyzed the fluoride intake of infants with various feeding regimes. The fluoride content of human milk ranges from 5-10 µg/l. Artificial baby milks are sold in several forms: ready-to-feed-liquid, concentrate, and powders. The fluoride content in these formulas can vary widely, usually depending upon the fluoride content in the water used to dilute them. Until 1978, manufacturers produced the infant formulas with local water supplies the fluoride content of which was often very high. Since then manufacturers have removed the major part of the fluoride of local water supplies in manufacturing the products. However, for the powder form of formulas, parents use unmodified local water to prepare the formula and the fluoride content can be as high as 980 µg/l . In order to reduce the risk of fluoridosis, the authors recommend that infant formulas not be prepared from fluoridated water and no fluoride supplements be given.

McVea KLSP, Turner PD, Peppler DK. The role of breastfeeding in sudden infant death syndrome, Journal of Human Lactation 16(1): 13-20, 2000.

A meta-analysis of 23 studies meeting the inclusion criteria showed that breastfeeding reduced the risk of sudden infant death syndrome (SIDS) on average by half. Although the studies try to reduce the effect of confounding factors, reduced risk of SIDS in breastfed infants may be affected by other parental or environmental factors, as well as by breastfeeding.