She follows breasts through their natural life cycle from puberty to changes during pregnancy, breastfeeding and menopause. And she wonders about their psycho-sexual meaning, writing, “big breasts get a lot of attention.”

Breasts are, indeed, bigger than ever, according to her research. The average-sized breast for an American woman is now a C cup and lingerie stores sell sizes from H to KK.

Or, more precisely, the average breast weighs just over a pound, but can double in pregnancy. The largest (enhanced) breast in the world is 21 pounds or a 38KKK, the equivalent of 1.3 gallons of liquid.