Gems from ILCA 2015 (No.1)


As it is World Breastfeeding Week I think I should relate a gem from the International Lactation Consultants Association conference held last week in Washington DC.

  • Kathy Dettwyler, Professor of Anthropology at the University of Delaware gave a great talk about the time of weaning (meaning ‘ceasing breastfeeding’ not adding solids).

Unencumbered by culture, societal and peer pressure, how long does biology tell us to breastfeed our young?

It seems reasonable to compare the timing of weaning in non-human primates, but as they have different lifespans, growth rates and times to mature we need to look at this using standards that allow us to compare species.

Dr Dettwyler has done extensive studies on this looking at:

  • Time of gestation (how long is the fetus in the womb)
  • Time to primary teeth
  • Time to secondary teeth
  • Time to sexual maturity
  • Time to triple or quadruple birth weight.

And what does she find?

In comparison to Gorillas and chimps and other apes the minimum time would be predicted to be 2.5 years and for several predictors it’s 5, 6 or 7 years!

Moreover, looking at average weaning time in 64 ‘traditional’ human cultures and taking the average of those averages, weaning time is about 2.5 years too.

What changed the Western human and when?

In the West breastfeeding routinely continued for 3 to 5 years or longer…..until the invention of formula. Then habits and attitudes changed.

Remember that expert committees such as the American Academy of Pediatrics recommend a MINIMUM of 1 year and the World Health Organisation a MINIMUM of 2 years (not 1 or 2 years).

So, take home sentence, breastfeed for as long as you both like.

Dettwyler, K. A. (2004). “When to wean: Biological versus cultural perspectives”. Clinical obstetrics and gynecology 47 (3): 712–723. doi:10.1097/01.grf.0000137217.97573.01