Summary of a Critical Look at Breastfeeding
(Note: Letters containing basically the contents below were sent to Surgeon General Benjamin and to responsible officials of the U.S. Department of Health and Human Services and the three academies of physicians that deal with this topic. As of over six months later, not one reply received has said anything to criticize any of the points below.)
The presumed benefits to infants of breastfeeding have been determined on the basis of observational studies, which can find "associations," from which only "inferences" can be drawn. This is acknowledged by Surgeon General Regina Benjamin, in her "Call to Action to Support Breastfeeding 2011" (p. 33).1 Observational studies conducted in Florida would find that sunshine is "associated" with a high death rate, and people could overlook the unusually advanced ages of many Floridians when finding this correlation of death rates with sunshine. In a similar way, many people overlook the fact that bottle-feeding mothers are unusually likely to be of low income1and to smoke.2 Conditions related to low income and smoking are known to lead to all of the adverse health outcomes that many people attribute to bottle feeding.3.
The American Academy of Family Physicians points out that most Americans born in the middle of the 20th Century were not breastfed; but by the end of the 1970's, breastfeeding had become the norm. So by now we have four decades of data that allow us to compare the health averages of the low-breastfed generation with those of the highly-breastfed young people who followed. As it turns out, not a single one of the disease reductions that would have been predicted on the basis of the claims about breastfeeding has materialized. In fact, outcomes have turned out to be significantly worse in all but one of the disorders that would have been expected to improve based on those claims, as found in an item-by-item examination of the claims and data.4
One of the disorders alleged to be reduced by breastfeeding: See what actually happened.
Looking at this chart, be aware that, after many low years, U.S. breastfeeding rates increased rapidly beginning in 1972.1 Then observe that, for each age group in these charts, obesity levels were not increasing significantly until the very first period in which part of that group's infancies occurred after 1972.
Obesity also increased among older Americans during these years, but it increased 125% more among the 6-19 age groups than among the 35-74 age groups. And the older group had a known reason for its increasing obesity, which was the great decline in physically-active jobs in agriculture and manufacturing during the last half century.5 That decline would not have substantially affected U.S. children.
Another disorder alleged to be reduced by breastfeeding: instead it more than tripled.
For the period from 1969–1970 to 1994–1995, Newacheck and Halfon (2000) reported that the prevalence of disabilities among U.S. children related to asthma (based on the National Health Interview Survey) increased 232%.6 Note that breastfeeding at six months in the U.S. increased 300% during those same years.1
Leukemia is also alleged to be reduced by breastfeeding, but it actually increased by 30% between 1975 and 1995, while (a) breastfeeding rates also increased greatly, and (b) while leukemia was not increasing among the adult population. When breastfeed- ing rates were flat, childhood leukemia incidence was also flat.4
The relationship between breastfeeding and childhood cancer in general is also of interest. The Western U.S. is the region lowest in known carcinogens, and therefore is the best region for seeing effects of a single source of those toxins. There, higher and lower breastfeeding percentages in 2001-2003 were very good at predicting childhood cancer rates in 2005-2009 -- see chart on left. The relationship is similar for the rest of the U.S. states – see www.breastfeeding-and-cancer.info.
Average exposures to dioxins, which are carcinogens and developmental toxins, are 86 times higher in breastfed infants than the EPA's estimated safe dose during a first year of breastfeeding (with still higher multiples early in the 12-month period)7 The accumulated dioxin toxic equivalency in infants that had had one year of breastfeeding was six times higher than that in formula-fed infants, according to an EPA study.8
Of 10 environmental chemicals that have been specifically identified as justifying research as possible causes of autism (Landrigan et al.), and of various toxins seen as causing harm to immunity development, most of them have been found in breast milk, some in high concentrations (dioxins and PBDEs, notably). Those two are known to have testosterone-reducing effects, which helps explain why autism and ADHD are found especially in males, since testosterone is important to neurological development.
European countries with the highest breastfeeding rates have the highest autism rates and highest childhood cancer rates, and the lowest-breastfeeding European countries (U.K., Ireland, France and Belgium) have the lowest rates of both diseases, with only one minor overlap between the two groups.9 Autism rates appear to be less than half as high in the low-breastfeeding countries as in the highest-breastfeeding countries.9a In a U.K. study (which is apparently the only major study published with such data as of May, 2012), 65% of children with autism had received major breastfeeding,9b compared with only 28% of children in the general population.10 (Comparing on basis of exclusive breastfeeding for at least four weeks or not, in UK and Northern Ireland.) A smaller U.S. study found similar results, but with a higher ratio of autistic breast-fed children to the general population (37% vs. 14%), when comparison was on the basis of a greater amount of breastfeeding.11 A 2011 study of all 50 U.S. states and 51 U.S. counties, carried out by a highly-published scientist who is also a Fellow of the American College of Nutrition, found that "exclusive breast-feeding shows a direct epidemiological relationship to autism" and also, "the longer the duration of exclusive breast-feeding, the greater the correlation with autism."12
Blacks breastfeed at about half as high a rate as whites, and their rates of autism and certain childhood cancers are about 50% lower than among whites.13 Hispanics are in between in all respects.
Breastfeeding mothers reduce their own body burdens of toxins by transmitting toxins to their babies in breast milk.14 This transmission of toxins takes place at the most vulnerable times of the rapidly-developing infants' lives. Certain researchers, seeing this excellent "decontaminating" of mothers by means of passing toxins on to their infants, still recommended breastfeeding "without any restrictions."
A fourth child’s risk of autism is half as high as that of a firstborn, on average, and the odds of being diagnosed with autism continuously decrease from first to later children.15 Toxins from breast milk decline greatly with succeeding births: Infants later in birth order are less likely to be breastfed, they are likely to be breastfed for shorter periods, and the milk they receive has toxin levels that have been reduced as a result of excretion to earlier-born infants during previous breastfeeding.16
Remember that, between 1972 and 2010, breastfeeding rates increased greatly in the U.S. There are no surveys that show consistent child health data for that entire period, but there are separate studies for major segments of that period, which regularly show unfavorable trends among children (such as shown on the left). These adverse trends occurred despite huge declines during those years in child blood levels of the developmental toxin, lead,17 and despite major other pollution reductions.
Bearing 1972 in mind as the starting year of the major increase in breastfeeding, note that ADHD went from being minor, not even named until 1980, to a prevalence of 11.4% among the 10-17 age group in 2010.(17a) In a 2004 study, it was pointed out that it was being "increasingly recognized that attention deficit hyperactivity disorder persists into adulthood."19a So it appears that it was only after infants of the mid- and late 1970's became adults that signs of real long-term seriousness of ADHD became apparent. Whatever precursors existed earlier were probably less significant than the ADHD that increased in the 1970's. Related to that, PBDEs have been increasing especially rapidly in the environment, and typical human milk appears to be over 50 times as high in PBDEs as formula.19 A major study found that children who had consumed breast milk containing top-quartile levels of PBDEs were 3.3 times as likely (as children below median) to have behavior test scores indicating likelihood of developing into ADHD.20
Diabetes: There was only one world region (Central/Eastern Europe) in which the 1995-2010 increase in breast-feeding rates was very exceptional, rising over 200%. (The second highest increase was less than 100%.)21 In a study of over 29,000 cases of childhood type 1 diabetes in Europe over the period 1989-2003, "rapid rise” of type 1 diabetes in children age 0-4 in this same Central/Eastern Europe region was seen as "especially striking."21a
Looking at the opposite extreme: Information about childhood diabetes provided by the Diabetes Mondiale Project Group, for 1990-1999, includes the following: "Trends estimated for continents showed statistically significant increases all over the world..., except in Central America and the West Indies where the trend was a decrease of 3.6%."22 The researchers did not try to explain why this region was exceptional. However, it is noteworthy that this region was apparently the only world region in which breastfeeding rates declined in recent decades.23
Asthma and allergies: These are alleged to be reduced by breastfeeding. However, 19 easily-found studies in medical journals (mainly the most recent studies) determined that these diseases actually increased in children who were breastfed, with several of the studies finding higher disease rates to correlate with longer durations of breastfeeding. Seven studies found that childhood diabetes increased with increased breastfeeding.23a
SIDS: The commonly-cited review of breastfeeding-related studies failed to mention that a clear majority of the high-quality studies about SIDS and breastfeeding found no favorable effects of breastfeeding. The historical record supports that lack of relationship. (See Section 9 of www.breastfeedingprosandcons.info; that site also shows that almost all of the other diseases alleged to decrease with breastfeeding instead actually increased )
Immune cells in breast milk are often considered helpful to an infant, but that may be untrue over the long term in the current hygienic conditions in developed countries, which already have greatly reduced microbial exposure compared with what our species became adapted to. A prominent doctor, based on studies, refers to the “critical importance of proper immune conditioning by microbes during the earliest periods of life.” The FDA says epidemiological evidence supports that position.24 Quoting from the UCLA Food & Drug Allergy Center: "Overwhelming evidence from various studies suggests that the hygiene hypothesis explains most of the allergy epidemic." Bear in mind that long-term immunity (such as is created by vaccinations) is created by challenges that stimulate development of the immune system. Consider where short-lived immune cells from outside the body, destroying microbes, fit into the picture of microbial challenges needed to stimulate development of the immune system.
Note that there are currently epidemics in childhood obesity, asthma, allergies and diabetes; and developmental disabilities (including autism and ADHD) have increased greatly; such increases apparently were unknown in the 1960's, when breastfeeding rates were low.25 Notice (above) that the increase of childhood diabetes was "striking" only where breastfeeding increased very sharply, and it declined only where breastfeeding declined. From pp.1 & 2, remember the many correlations of high and low rates of autism, cancer and obesity with highs and lows of breastfeeding. Bear in mind that U.S. breastfeeding rates increased several-fold between 1972 and the present;1 if that feeding had been genuinely beneficial (in our current low-microbial-exposure times), there should have been declines in children's disabilities, rather than the substantial increases that actually occurred.
Gestational vs lactational exposure: Many people make the assumption that the greatest exposure of a baby to maternal toxins would occur during pregnancy, but that is apparently not the case. According to what is probably the most thorough study on this subject of infant absorption of toxins from mother's milk vs. from fetal absorption, "Significantly more (10 to 20 times) of a mother's body burden of persistent organohalogens is transferred to the infant via the milk than by the transplacental route." (Note that dioxins, PCBs and PBDEs, all of which are parts of the diesel emissions that are especially implicated with autism, are included among organohalogen compounds.) Tests with animals have confirmed the above, with even higher ratios of lactational vs. transplacental transfer.26
A logical question that comes up, then, is Should parents be unreservedly advised by medical authorities to breastfeed their infants, while the parents remain uninformed about the above important points?
Further relevant information, with links to sources, can be found at www.breastfeeding-health-effects.info.
- (1) -- "Surgeon General's Call to Action to Support Breastfeeding 2011", p. 33, Table 2 and Figure 1 at
- (2) - Breastfeeding Initiation and Duration: A 1990-2000 Literature Review Cindy-Lee Dennis, RN, PhD JOGNN in Review, Vol. 31, No. 1 (abstract at onlinelibrary.wiley.com/doi/10.1111/j.1552-6909.2002.tb00019.x/abstract); also Gallup Well-Being, 3/21/08 Among Americans, Smoking Decreases as Income Increases by Rob Goszkowski
- (3) Child Health Care and Social Factors: Poverty, Class, Race by B. Starfield, MD, MPH, Head, Div. of Health Policy, Johns Hopkins Univ., and many other sources listed in footnotes 9 and 10 at www.breastfeeding-benefits.net
- (5) For more information about obesity increases in the older groups, and for information about chemicals in breast milk that probably underlie increases in obesity following increases in breastfeeding, see www.breastfeeding-and-obesity.info
- (6) Cited in The Future of Disability in America, Ch. 3, p. 77. Inst. of Medicine Committee on Disability in America; Field MJ, et al., ed., Nat'l Acad. Press; 2007 bookshelf ID: NBK11437 at www.ncbi.nlm.nih.gov/books/NBK11437
- (7) U.S. EPA ”Estimating Exposure to Dioxin-Like Compounds” - Vol. I, U.S. EPA/600/8-88/005Ca., rev. 2005, for typical infant exposure, and EPA document at www.epa.gov/iris/supdocs/dioxinv1sup.pdf regarding safe dose.
- (8) EPA Home/Research/Environmental Assessment: An Evaluation of Infant Exposure to Dioxin-Like Compounds in Breast Milk, Matthew Lorber et al. at at www.ncbi.nlm.nih.gov/pmc/articles/PMC1240886/pdf/ehp0110-a00325.pdf
- (9) Breastfeeding rates from WHO, European HFA Database; autism data from many sources, cited in www.pollutionaction.org, third link, Sections 1.2.s.4-5; cancer rates from "International Comparisons of World Age-standardised Incidence Rates for Childhood Cancer: 1998-2000," Figure 4, from a website of Queens Univ., Belfast, Ireland, at http://www.qub.ac.uk/research-centres/nicr/FileStore/PDF/Filetoupload,176738,en.pdf ; also other sources.
- (9a) for country-by-country data, see Section 1.2.p of http://www.pollutionaction.org/breastfeeding-and-autism-and-cancer.htm .
- (9b) "Trends in Developmental, Behavioral and Somatic Factors by Diagnostic Sub-group in Pervasive Developmental Disorders" pp. 10, 14 P. Whiteley (Univ. of Sunderland, UK), et al., Autism Insights 2009:1 3-17 at www.la-press.com/trends-in-developmental-behavioral-and-somatic-factors-by-diagnostic-s-article-a1725
- (11) Presentation by P.G. Williams, MD and L.L. Sears, MD, at INSAR conference in Kentucky, found at imfar.confex.com/imfar/2010/webprogram/Paper6362.html
- (12) Autism rates associated with nutrition and the WIC program. Shamberger R.J., Phd, FACN, King James Medi-cal Laboratory, Cleveland, OH J Am Coll Nutr. 2011 Oct;30(5):348-53. Abstract at www.ncbi.nlm.nih.gov/pubmed/22081621
- (13) www.cdc.gov/breastfeeding/data/NIS_data/2000/socio-demographic.htm; also American Journal of Public Health. 2003 December; 93(12) "Low Breastfeeding Rates and Public Health in the United States" J. H. Wolf, PhD, re breastfeeding rates among blacks; for childhood cancer rates among blacks, seer.cancer.gov/publications childhood/ infant.pdf; for autism rates, 2007 National Survey of Children's Health, Child Trends DataBank
- (14) Decrease in milk and blood dioxin levels over two years in a mother nursing twins: estimates of decreased maternal and increased infant dioxin body burden from nursing. Schecter A et al, Department of Preventive Medicine, State University of New York, Health Science Center-Syracuse, USA Chemosphere. 1996 Feb;32(3):543-9.
- (15) American J.of Epidemiology, Dec. 2008; 168(11): 1268–1276. Pub.online 2008 October 21. doi: 10.1093/aje/kwn250 "Advanced Parental Age and the Risk of Autism Spectrum Disorder" Maureen S. Durkin et al.
- (17) In 1976-1980, 88.2 percent of children 1 to 5 years of age had blood lead levels that were more than 10 micrograms of lead per deciliter. By 2003 that had declined to 1.6 percent. CDC, National Center for Environmental Health. Lead research, as quoted by Trends Data Bank. www.childtrends.org/databank Accessed July 21, 2005
- (18) The Future of Disability in America. Ch. 3 Institute of Medicine Committee on Disability in America; Field et al, ed National Acad.. Press (US); 2007 bookshelf ID: NBK11437 www.ncbi.nlm.nih.gov/books/NBK11437/
- (20) Lactational Exposure to Polybrominated Diphenyl Ethers and Its Relation to Social and Emotional Dev't among Toddlers Hoffman, et al., Environ Health Perspect. 10/2012; www.ncbi.nlm.nih.gov/pmc/articles/PMC3491946/
- (21) Developing World data from www.childinfo.org/breastfeeding_progress.htm. Other data from WHO/HFA datab.
- (21a) Incidence trends for childhood type 1 diabetes in Europe 1989-2003 and predicted new cases 2005-20: a multicentre prospective registration study CF Patterson et al., www.thelancet.com, Vol 373, June 13, 2009
- (24) Dr. Richard Blumberg, in Cell Research, advance online publication 24 April 2012; doi: 10.1038/cr.2012.65 "Early exposure to germs and the Hygiene Hypothesis," Division of Immunology, Children's Hospital Boston, Harvard Medical Sch'l; and FDA website, at www.fda.gov/biologicsbloodvaccines/resourcesforyou/consumers/ucm167471.htm
Jensen, A.A. et al, Chemical Contaminants in Human Milk, CRC Press,
Inc., 1991, p 15. Ahlborg et al., Risk Assessment of Polychlorinated Biphenyls (PCBs),
Nordic Council of Ministers, Copenhagen. Report NORD 1992; 26