Can human males produce breast milk?

Bijoy Venugopal
Gee Whiz!
2 November 2011

Much fuss has been made of a male goat in Lucknow that has started producing milk (watch the video). Now here's a primer for those who can't tell a male goat (for that matter, most four-legged mammals) from its biological mate: Look between the hind legs. This can be tricky, for female goats — or nannies — have two udders (unlike cows, which have four). In males, called billies, the corresponding appendage to be found there is the scrotum. Never expect milk from there — because that is NOT milk.

But hello, Sheru in Lucknow actually produced milk. Proof is in the white liquid squirting from his barely visible udders.

Is this some divine milkman at work? Sorry to burst your milky bubble, but no.


The last time I wrote about goats, people ganged up to get mine. So I'll keep this one short and pointed — the horns of the dilemma, I mean.

First off, Sheru isn't the first or the only billy-goat in the world to be the cynosure of such celebrity. Lactating male goats have been reported from China — they always beat us to it, don't they? — and Abu Dhabi and Brazil.

As with most mammals including you and me, billy-goats have poorly developed mammary glands. And nipples, which are outlets for the secretion produced by these glands.

In the normal course, male mammals do not lactate. But here's a fact: It is not unheard of for men to produce milk.

The American scientist and author Jared Diamond, in a 1995 article titled "Father's Milk" published in Discover magazine, argued: "Evolution just didn't design us men to utilize our potential to lactate, even though we have the necessary anatomic equipment, physiological potential, and hormone receptors."

Male nipples intrigued even Aristotle and Charles Darwin, sentient men with a formidable reputation for taking nothing lying down. In his brilliant path-breaking (and controversial) treatise, The Descent of Man, Darwin wrote: "It is well known that in the males of all mammals, including man, rudimentary mammae exist. These in several instances have become well developed, and have yielded a copious supply of milk."

Some social scientists contend that contemporary cultural stereotypes regarding parental roles have led to the alienation of the father's role in nurturing infants. That argument is central to anthropologist Barry Hewlett's studies. He, for one, must not have been surprised (or outraged) when in 2002 a paper reported that a widowed Sri Lankan man was breastfeeding his children. In fact, so moved was he by the sight of his crying infant daughters, whose mother had died in childbirth, that he offered his elder child his breast to comfort her. To his surprise, he started to lactate. Doctors approached for their view of this anomaly commented that stimulation of the mammary gland may have stimulated the production of the hormone prolactin, which is known to induce lactation among several other effects.

Literally, then, man's milk must be the "milk of human kindness" that Shakespeare wrote about in Macbeth.

Hewlett, observing Africa's Aka pygmies, reported that men of the tribe share up to 70 percent of parenting duties, including suckling infants to soothe them. He published these findings in the so-called civilized world to mixed reactions. Some men wrote in expressing relief, confessing that they had often felt the impulse to nurse their infant children amid confused paternal urges. The majority of readers, unsurprisingly, found the idea revolting; some even deplored it as deviant behavior tantamount to sexual abuse.

In fact, even the idea of mothers suckling infants in public is considered by some cultures as offensive, though it is a fundamental maternal function. This disconnect with our visceral identity has deteriorated to the extent where some of us live in denial that milk is a source of nourishment derived from organic, animal origins — not from a sachet or a carton as our supermarket-raised generation has been led to imagine. We encountered such mixed sentiments when we carried a slideshow two months ago about a Cambodian boy who was suckled by a cow.

We digress. Backtrack to what's getting our goat.

Experts reason that extraordinary high levels of female hormones, normally present in males, may trigger lactation in some individuals. Castrated animals — like bullocks and horses — have been known to display female characteristics including turgid mammary glands. Humans divested of testicles have been reported to display similar "effeminate" morphological characteristics — the transgender hijra is a case in point. New research has revealed that men are susceptible to breast cancer due to hormonal imbalances after the age of 40.

In goats, too, extraordinarily high levels of prolactin might cause male animals to lactate and display female characteristics. And it may not be entirely wrong to blame some of these effects on genetically modified animal feeds.

In fact, games genetic engineers play have led us to live amid dangerous realities. The Russians, ever ahead in the race to make beasts of burden work overtime, have experimented with genetically modifying goats to produce human breast milk.

Back to Sheru, our celebrity from Lucknow. While his isn't a cock and bull story, let's not be sheepish in acknowledging the fact that men can, too.