French novelist Marcel Proust famously wrote in 1913 that asparagus “transforms my chamber- pot into a flask of perfume.”

Asparagus is a nutrient-dense flowering vegetable belonging to the lily family.

The edible portion consists of young, tender spears that emerge from the soil during the spring growing season. This vegetable is available in green, white, and purple varieties, with green asparagus being the most widely consumed. Asparagus is appreciated for its delicate texture, distinctive flavour, and rich nutritional profile. It’s an excellent source of folate, a B vitamin essential for red blood cell production, as well as vitamin K, which supports normal blood clotting. Asparagus also provides dietary fibre and antioxidants that help protect the body from disease and promote overall health.

Many of us have been enjoying this in-season spring delicacy, but have you noticed that your urine can smell quite odiferous after eating it? I have and it got me wondering, is it just me, or does “asparagus pee” happen to everyone? A bit of research later, I found out that smelly asparagus pee happens to everyone, but only some of us can smell it.

After we digest asparagus, the vegetable’s sulfur-containing amino acids (the building blocks of protein) break down into smelly chemical components particularly asparagusic acid. These components are “volatile” which means they float in the air. The odour wafts upwards as urine leaves the body. The volatile components can be detected as early as 15 minutes after you eat asparagus, andthe intensity of the smell depends on the amount of asparagus eaten and how hydrated you are.

Only 40 per cent or less of the population has the special gene required to smell asparagus’ volatile compounds. So the issue is not whether or not your pee is smelly; it’s whether you’re able to smell it! So if you can smell a funny odour in your pee after eating asparagus, you have a sensitive (and I think, highly evolved) nose.