For the first time,
Australian researchers have demonstrated exactly how chemotherapy affects a
cancer patient’s ability to taste.
The study, published today
in science journal PLOS ONE, proves chemotherapy initially reduces a patient’s
taste function, appetite and food enjoyment, but that taste function typically
returns two months after treatment finishes.
The study involved 52
Victorian women being treated for breast cancer with the same types of
chemotherapy. Researchers tested each patient’s ability to correctly identify
salty, sour, bitter, sweet and umami tastes before, during and after
chemotherapy.
They also monitored
patients’ food intake, and found those who experienced greatest taste change or
who lost interest in eating chocolate during chemotherapy consumed fewer
kilojoules and protein, and experienced more weight loss.
Lead author Dr Anna
Boltong, who is Cancer Council Victoria’s Head of Cancer and Information
Support Service, said this was the first time the taste function of cancer
patients had been tested more than once within a single chemotherapy cycle, and
the first time patients were followed up later to assess all impacts.
“The research proved that taste per se, as opposed to other elements of
flavour or related senses like smell, is adversely affected during chemotherapy
but – most importantly - that taste function does return,” Dr Boltong said.
“Our findings mean we can now, with
confidence, forewarn patients of taste and related side-effects during
chemotherapy as well how long such symptoms are likely to last.”
The
next step for researchers will be investigating how to establish a simple,
predictive test to work out which patients are most likely to lose or gain
weight during chemotherapy. Dr Boltong said chocolate could hold the key.
“Among
patients tested we found that enjoyment of chocolate decreased significantly
after chemotherapy began, and that this was associated with them consuming
fewer kilojoules, protein and fat. So, a chocolate taste test could be the
answer.”
The
study showed symptoms (ability to identify salty, sour and umami tastes,
reduced appetite and decreased food enjoyment) appeared within the first 4-6
days after chemotherapy was given, and gradually subsided until the next chemo
dose (typically 2-3 weeks later). It also showed, for the first time, that
taste function returns for most patients two months after chemotherapy
concludes.
To access the full paper titled: “A
prospective cohort study of the effects of adjuvant breast cancer chemotherapy
on taste function, food liking, appetite and associated nutritional
outcomes" visit http://dx.plos.org/10.1371/journal.pone.0103512