&
The heat in chilli is caused by a chemical
called capsaicin, which binds to the TRPV1
proteins in the nerves that sense pain and
heat. If these receptors are continually
stimulated by regular spicy meals then the
nerve cells ‘turn down the volume’ by adding
phosphate groups to the receptor proteins.
This causes the protein to alter its three-
dimensional shape and reduces its ability
to bind to capsaicin, so you become less
sensitive. Our sense of taste also naturally
decreases as we get older, so food that used
to be intolerably spicy might now produce
just a pleasant tingle. LV
Can you learn to like
spicy food?
Quite possibly – and preventing it from
happening has long been a key concern
in interplanetary exploration. In 1964, the
Committee on Space Research required that
nations take care to sterilise space probes
to minimise the risk of contamination by
Earth-based organisms. As a result, probes
are routinely treated with heat, radiation and
disinfectants before launch. RM
Could we seed life on
another planet?
Allergies are caused by an overactive
immune system. There’s evidence that this
is inherited, but many studies have also
shown that growing up in an excessively
clean environment can trigger allergies.
People from big families tend to have been
exposed to more bacteria and have aWhy do some people get allergies?
On his days off from
tormenting Batman, Bane loved
to frolic among the flowerslower chance of developing allergies. If you
had skin cream containing peanut oil as a
baby, you are more likely to be allergic to
peanuts as an adult, and soy in formula milk
may also trigger peanut allergies, perhaps
because the proteins have similar molecular
shapes. LV