Here is the last in my Katherine Dettwyler series. Part of a lecture from one of her Anthropology classes, which I’ve done my best to convert into a post.
(shared with permission)
The Anthropological: Breastfeeding & Weaning
- Kingdom- Animalia (animal)
- class- Mammalia (mammal)
- order- Primata (primate)
Humans are most closely related to Great Apes. (Organgutans, Gorillas, Chimpanzees)
Great Ape Nature: Social, reliance on learned behavior, and able to make and use tools.
Human Nature: Humans nature differs from great ape nature only in degree, not kind.
- Patterns of beliefs and practices, that lead to different styles of parenting and different expectations of children
- patterns of ideas and behaviors that shape the way we live
- culture is shared and learned
- culture can be adaptive or maladaptive
- culture can change rapidly or be very conservative and resistant to change
Breastfeeding in Mammals: Like all other mammals, humans have mammary glands that produce fluid, known as milk. Lactation/breastfeeding provide all mammal offspring with: Protective factors to prevent disease Curative factors to recover from disease Essential growth factors for normal development of the brain and body State regulation (respiration, heart rate, blood pressure, emotional comfort). The nutritional value of breast milk (and thus the nutritional function of breastfeeding) developed after the other functions in the evolution of lactation. The nutritional value of all mammalian milks have been shaped by the specific needs of each species. Human milk meets the specific needs of humans as large-bodied, large-brained, slow-growing primates
Whenever we design cultural systems of beliefs and behaviors that contradict our evolved capacities and needs, there will be a price to pay.
Formula fed babies (*more commonly seen in areas of the world where potable water and nutrient-dense foods are lacking*) are at higher risk of:
- Haemophilus Influenza
- Meningitis in Preterm Infants
- Necrotizing Enterocolitis
- Otitis Media (ear infection)
- Pneumococcal Disease
- Respiratory Infections (general)
- Respiratory Infections (from exposure to tobacco smoke)
- Respiratory Syncytial Virus
- Sepsis in Preterm Infants
- Anemia and Iron Deficiency
- Autoimmune Thyroid Disease
- Constipation and Anal Fissures
- Cryptorchidism (undescended testicle)
- Esophageal and Gastric Lesions
- Gastroesophageal Reflex
- Inguinal Hernia
- Lactose Malabsorption
- Morbidity and Mortality
- Pyloric Stenosis
- Sudden Infant Death Syndrome
- Toddler Illnesses
Maternal Health- Research also suggests women who do not breastfeed have statistically higher rates of*:
- Breast Cancer
- Endometrial Cancer
- Esophageal Cancer
- Hodgkin’s Disease
- Ovarian Cancer
- Thyroid Cancer
- Uterine Cancer
- Poorer Cardiovascular Heath
- Higher rates of Diabetes
- Poorer Emotional Health
- Higher Fecundity/Fertility
- More hot flashes during menopause
- More Osteoarthritis
- More Osteoporosis
- Slower Postpartum Weight Loss
- More Rheumatoid Arthritis
- Less Sleep: 40-45 minutes less per night
- More Systemic Lupus Erythematosus
*It is important to note that breastfeeding does not reduce your chance of getting any of the above conditions. Many women who never have children or breastfeed will go on to live healthy disease-free lives, while many women who have breastfed will still go on to develop the conditions listed. One must take into account genetic risk factors, as well as other environmental risk factors that come into play. *
Culture can change rapidly. Our genetic legacy – our anatomy, physiology, and behavior – as animals, mammals, primates, Great Apes, and humans – changes much more slowly.
The Milk Line:
Along which the mammary glands develop in pairs; it extends from the armpit to the groin. Some animals have many, some have two, some have some; some, such as the elephant have only the first pair (in armpits); humans have only the second pair, on our chests; some animals have only the last pair (or last two pairs) coalesced into an udder near their groin.
Human Milk: Humans have low levels of protein & fat in mother’s milk.
Infants are Fairly continuous feeders: Multiple times per hour, around the clock, until longer sleep cycles and quiet alert times gradually develop, and baby adapts or accommodates to mother’s preferences and schedule
Where allowed unrestricted access, will continue to nurse several times an hour for a few minutes each time through toddlerhood and beyond (sleep more at night, but nursing several times a night is typical/normal until weaning)
- During the first few months, the more often the baby nurses, the more milk the mother produces
- After about 4 months, demand drives supply – the more milk the baby removes, the more milk the mother makes
- More frequent nursing leads to more milk, with higher fat concentrations
- Our late age at reproductive maturity predicts 3-6 years of breastfeeding (based on 12 to 20 years for reproductive maturity)
- Primates that nurse for one year have their own offspring at the age of 4 years
- Most mammals, including primates, nurse from birth until the end of infancy, where infancy is defined as “birth to the eruption of the first permanent molars”
- In humans, these are the teeth known as the 6-year molars; they erupt in the back of the mouth behind the deciduous (baby) teeth about the same time the first baby teeth (the ones in front) are falling out.
Facts About Human Weaning:
- The instinct to suck/suckle persists until about the age of 6-7 years
- The immune system reaches maturity around 6-7 years
- The brain has completed most of its growth by 6-7 years
- Children are much more independent by this age than they are at 1-2-3 years of age
- Range of 2.5 years to 7.0 years as natural age of weaning in modern humans
- Many cultures around the world where all children nurse 2-4 years or longer
- Many children around the world, including the United States and Australia, who nurse 2-4 years or longer, including up to and beyond the predicted upper limit of around 7 years
Human children expect to be the primary parenting focus of their mother’s attention for many years before a younger sibling is born.
Average human birth spacing (without intervention) would be at least 4 years between births, with 6-7+ years being even more optimal.
It is normal and healthy for children to breastfeed for many years