French novelist Marcel Proust once fancifully described the smell as "transforming my humble chamberpot into a bowl of aromatic perfume" but it seems he was in the minority as three in five people are unable to even detect the odour, according to a study published on Wednesday.

From data on 6,909 participants, 58 percent of men and 61.5 percent of women had asparagus anosmia, or the inability to detect the smell, according to the results in the BMJ medical journal's Christmas edition, traditionally reserved for studies that are quirky but scientifically sound.

— The Harvard School of Public Health adds to the body of research on the mystery of asparagus pee. Read more at Scientists sniff out answer to 'asparagus pee' mystery at The Telegraph. An older (2013) study from genetic testing service 23andme is discussed at A Gene for Smelling Asparagus in Urine? at Mind The Science Gap; for those of you who have had genetic testing, the SNP that article is talking about is rs4481887 (see Asparagus Metabolite Detection).

The human nose is an incredible instrument with astonishing abilities. For example, in terms of our olfactory detection threshold. There’s an odor we’ve been working with quite a bit, and its detection threshold is 10 to the power of minus 12 moles. And yet you can still smell the difference between a regular Olympic pool and an Olympic pool into which we’ve introduced a single drop of that liquid.

— "That liquid" being sweat. Read more at We base the most important decisions of our lives on smell at Haaretz.

“Even though we may not be aware of it, the sense of smell influences how adults process emotional and social information to guide their decisions and behavior. Our findings establish that, beginning at the age of five, smell also influences children’s emotional decisions,” said cognitive neuroscientist Valentina Parma, PhD, one of the study’s authors.

— A study at Monell Center reveals that "children older than five use odor information to evaluate faces"; read more at With Eyes or Noses? How Young Children Use Sensory Cues to Make Social Decisions.

As they reported this fall in the Journal of the American Chemical Society, the researchers discovered that the same receptors in the nose that pick up these unpleasant-smelling molecules also bind with particles of copper that reside in nasal mucus. The metallic partner amplifies a thiol's intensity by up to 1,000 times. And in experiments in which the scientists created thiol receptors that could not bind with copper, sensitivity to the odorant all but disappeared.

— Read more at Chemists Discover Why the Nose Is Hypersensitive to Sulfur Odors at Scientific American.