Rainbow fluids
A common migraine medication has an uncommon side-effect: it can turn blood green. People with urinary catheters can sometimes produce purple pee.
Camera pill
There’s a pill you can swallow with a little camera inside. It’s great for identifying gastrointestinal damage, and usually comes out the other end in a day or two. Usually.
I ate a glass piano
Princess Alexandra of Bavaria was a noted author and translator in the mid-19th century. She also firmly believed that as a young child she had swallowed a grand piano made of glass.
Earworm cure
An earworm is a piece of repetitive memorable music that gets stuck in your head. How do you cure it? Chew gum.
Gut brains
The human gastrointestinal tract has half a billion neurons embedded in its lining. Often described as the “second brain,” it can act and react autonomously, and even has its own supply of serotonin and dopamine.
Handed, footed, eyed
Everyone is born either left- or right-handed (or, rarely, mixed-handed or ambidextrous). But everyone also has a dominant foot, and a dominant eye.
Placebo surgery
When trialling a new medicine, it’s standard practice to test it against a placebo medicine. But what do you do if you’re trialling a new surgery instead?
The king, the twins, and coffee vs. tea
King Gustav III of Sweden was so convinced that coffee was bad for you that he enlisted two criminal twins to prove his case scientifically.
Kidney stone paradox
Statistics are tricky. Consider this: of two treatments for kidney stones, Treatment A is better on average for large stones and small stones. But consider all stones together and Treatment B is better. This is Simpson’s paradox.
Nasal alternation
Only one of your nostrils is fully open at any one time. The nasal cycle means that one of your nostrils is constricted for various physiological reasons, and this swaps around every two and a half hours.
Immortal dog
Some time more than 200 years ago, a dog or wolf in China or Siberia got cancer. It was a strange type of cancer: the cancer cells were contagious. That cell line is still alive today, and will probably be alive forever.
Most painful sting
Justin O. Schmidt, an entomologist from the United States, has ranked the relative pain caused by bee, wasp, and ant stings. How do you find that out, though? Easy enough, you just sting yourself.
Dead rabbit pregnancy test
In the 1930s there was a reliable and accurate way to find out if you were pregnant or not. But you had to kill a rabbit.
Blood type personality
Everyone in Japan knows that people with Type AB blood are creative, intelligent, and untrustworthy. Wait, what?
Micromorts and microlives
How do you effectively communicate risk when something is risky over the medium or long term? Measure the risk in micromorts (the one-in-a-million chance of dying) and microlives (half an hour of extra life).
