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By James W. Prescott, Ph.D. – Institute of Humanistic Science

From Touch The Future Newsletter, Spring 1997.

And although it is not the norm in most industrial cultures, UNICEF and the World Health Organization both advise breast-feeding to "two Years and beyond." Indeed, a child's immune response does not reach its full strength until age five or so.
How Breast Milk Protects Newborns
Jack Newman, M.D.
Scientific American, December 1995

The crucial role of breastmilk with its immunological agents for protecting the newborn/infant against disease and illness is well known, as is its essential role in promoting the development of the infant's own immune system. It is less well known that the infant's immune system does not reach maturity until about 5-6 years of age. This developmental immaturity of the infant's immune system can serve as a guide to appreciating the developmental immaturity of the infant's brain with its various structural, neurochemical and electrophysiological processes that extend in development well beyond the 5-6 years of maturity for the immune system.

It is also well known that sensory stimulation is like a nutrient which is essential for the normal growth, development and functioning of the brain and that sensory deprivation during the formative periods of brain development induces developmental brain abnormalities of both structure and function (neurochemical and neuroelectrical activity). These sensory deprivation processes that involve the emotional senses of body touch, movement and smell have been well described in failed affectional bonding in the mother-infant/child relationship that results in behavioral abnormalities of depression, impulse dyscontrol, violence and substance abuse; and in impaired immunological functioning in mother deprived infants.

One of the brain neurochemical transmitter substances–serotonin–has been shown to be significantly reduced under conditions of failed mother-infant affectional bonding. Other studies involving adult depressed and violent persons and criminals have clearly documented deficits of brain serotonin in these persons who have a history of suicidal and assaultive/homicidal behaviors. Unfortunately, these studies have not evaluated the extent of failed maternal-infant/child affectional bonding in these depressed and violent adults and it has been assumed that the brain serotonin deficits found in these subjects was due to some genetic factor rather than to maternal-infant environmental factors identified in this essay.

This error of interpretation is compounded by the failure to realize that there is another neurobiological mechanism involved in the development of brain serotonin–tryptophan–a precursor amino acid essential for the development of brain serotonin which is richly present in colostrum and breastmilk but absent in formula milk. Thus, two distinct and different neurophysiological mechanisms have been identified that contributes to deficits in brain serotonin: a) failed physical affectional bonding in the maternal-infant/child relationship (sensory processes); and b) the amino acid tryptophan present in colostrum and breast milk but absent in formula milk (neurochemical processes).

Millions of years of mammalian evolutionary biology have naturally joined these two different psychophysiological processes together in the act of breastfeeding where they are clearly mutually reinforcing for one another. Only in the human mammal do we find the newborn separated from its mother at birth and the mother not breastfeeding its newborn and infant. We have discovered that such aberrant behaviors which violate millions of years of evolutionary biology and psychobiology have exacted a terrible price upon the physical, emotional and social health of the newborn and infant and as a child, adolescent and adult–depression, impulse dyscontrol, violence and substance abuse.

There are, of course, other neurochemical processes of the brain that are involved in affiliative bonding and sexual behaviors, e.g. oxytocin which has traditionally been known for its effects on uterine contraction and milk ejection. Oxytocin (OT), however, has other powerful effects, e.g. studies have shown that brain OT can selectively decrease the rat pup's separation response from its mother and modulate social and sexual behaviors in male squirrel monkeys which were related to the social dominance status of the monkey and to levels of gonadal steroids which influence oxytocin receptor density. Other animal studies have shown that direct injection of OT into the brain produced an immediate inhibition of sexual activity in sexually active prairie voles, thus demonstrating the role of oxytocin in sexually affiliative and satiety behaviors.

Studies in human subjects have shown direct relationships between blood OT levels, sexual orgasm and the degree of sexual pleasure experienced, as reported by multi-orgasmic woman participating in these studies. Other studies in male subjects have shown as much as a 362% increase of blood OT from baseline to orgasm and that naloxone blocked this effect. Additionally, naloxone (a blocker of endorphin/morphine effects, i.e. pleasure) was found to significantly reduce sexual arousal and pleasure.

The above findings suggest, among other predictions, that adults who have been breastfed for "two years and beyond" will have enhanced integrative brain development for the experiencing of sexual affection, pleasure and bonding which would translate into more stable psychosexual and marital relationships, e.g. diminished divorce rates (see Table 1).

The above findings, taken collectively, support an evolutionary biological and psychobiological perspective that breastfeeding is essential for normal brain development, particularly, those brain processes associated with depression and violence and their opposites of pleasure, affiliative social and sexual behaviors; and peaceful-harmonious behaviors. (There are many other neurobiological properties of breastmilk that are important for normal brain development and behavior which are not found in formula milk but cannot be reviewed herein, e.g. long-chain polyunsaturated fatty acids (LCPs) which have been linked to enhanced intellective-cognitive functioning in breast-fed vs formula-fed infants.)

The increasing emphasis in industrialized societies to place infants and children in institutionalized day care assures the lack of affectional bonding between mother and infant/child with all of its deleterious consequences (see review of Dr. Peter S. Cook's book: Early Child Care: Infants & Nations At Risk, pp. of this newsletter).

For all of the above reasons (and others), it has been my challenge to the criminal justice system to find one murderer, rapist or drug addict in any correctional facility in America who has been breastfed for "two years and beyond", as recommended by the World Health Organization. My proposed studies of adults who have been breastfed for "two years and beyond", when conducted, would provide a strong data base to support the above stated relationships and to call for a national health policy that would support mothers being nurturant mothers that would include breastfeeding for "two years and beyond". If such a national health policy were to be implemented, it would transform our culture of violence into a culture of peace.

The available cross-cultural data on "primitive" cultures are highly supportive of these expected relationships. Table 1 summarizes the highly affectionate and nurturant behaviors of cultures that breastfeed for 2.5 years or longer. Table 2 summarizes the social-behavioral characteristics of those highly nurturant cultures which are found to be egalitarian, affectionate, sexually expressive and non-violent cultures.

In summary, the lessons to be learned are clear. If Homo sapiens is to survive as a species, he/she must return to the "life plan" of Mother Gaia who, through her wisdom of millions of years of evolutionary biology and psychobiology, has provided for the intimate physical affectional bonding between mother and her offspring which establishes the foundation for later sexual affectional bonding and for human love itself. For without human love there can be no survival of Homo sapiens.

"As the body is prior in order of generation to the soul, so the irrational is prior to the rational. The proof is that anger and wishing and desire are implanted in children from their very birth, but reason and understanding are developed as they grow older. Wherefore, the care of the body ought to precede that of the soul, and the training of the appetitive part should follow; none the less our care of it must be for the sake of the reason, and our care of the body for the sake of the soul."
Politica (c. 350 B.C.)



Social-Behavioral Characteristics of Cultures Where Weaning Age Is 2.5 Years Or Longer (% Communality of Cultures)

% Correct
Sample Size
# Cultures
Social-Behavioral Characteristics

79 24 Religious Specialists Are Part-Time Not Full Time
74* 19 Age Of Toilet Training Is Two Years or Greater
71 52 Infant Age of Reduced Contact With Mother Is > Two Years
71 28 High Number of Food Taboos During Pregnancy
70* 20 Divorce Rate Is Low
70 44 Child Conflict Over Nurturant Behavior Is Low
68* 31 Early Satisfaction Potential Is High
68 38 Early Oral Satisfaction Potential Is High
64 70 Indulgence of Child Is High
63 63 Transition Anxiety Between Infancy-Childhood Is Low
63 63 Infant Physical Affection Is High
59* 32 Low Presence Of Adolescent Peer Groups In Public Gatherings
59 69 Commonly or Occasionally Polygynous Rather Than Monogamous


Social and Behavioral Characteristics of Cultures That Have High Infant Physical Affection (% Communality of Cultures)

% Correct
Sample Size
# Cultures
Social-Behavioral Characteristics

81 27 Religious activity is low
80 66 Overall infant indulgence is high
78 18 Dissociation of sexes at adolescence is high
76 17 Witchcraft is low or absent
76 17 Belief in reincarnation absent
74 65 Degree of reducing infant needs is high
73 49 Torture, mutilation and killing of enemy captured in warfare is absent/negligible
72 36 Incidence of theft is low
71 38 Fear of human beings is high
68 65 Low Child anxiety over responsible behavior
68 59 Immediacy of reducing infant needs is high
68* 22 Superordinate justice is absent
66* 41 Asceticism in mourning is low
66* 50 Invidious display of wealth is low
65 63 Low Child anxiety over obedient behavior
65 63 Low Child anxiety over obedient behavior
65 63 Infant physical pain is low
65 63 Weaning age is 2.5 years or longer

  1. All of the above relationships are statistically significant with p < .05
    (*) except for starred items where: .10< p < .05
  2. Derived from R. B. Textor (1967): A Cross Cultural Summary, HRAF Press New Haven
  3. Comparisons involve cultures that breast-feed longer than 2.5 years vs. those that breast-feed less than 2.5 years. Comparisons involving no breast-feeding does not exist in primitive cultures. Studies comparing individuals breast-fed for 2.5 years or longer vs. no breast-feeding in contemporary cultures are urgently needed.

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