Researchers Look into Health Benefits of Active Component of Chili Peppers
By Science
News Staff / Source
Capsaicin is
the chemical compound found in the internal membranes of chilli peppers that
produces the burning sensation in the mouth when ingested.
The
heat varies depending on the variety of pepper and is measured on the Scoville scale.
Applied
to the skin as a topical cream, capsaicin can relieve some arthritis pain or
the pain associated with postherpetic neuralgia, the most common complication
of shingles.
At
first application, the cream often causes a burning sensation, local redness and
inflammation.
So
are we suffering additional pain to relieve the initial pain?
“It
may seem paradoxical, but yes, we’re fighting fire with fire,” said Professor
Réjean Couture, a researcher in the Department of Pharmacology and Physiology
at the University of Montreal.
“Capsaicin
activates a nociceptor (pain receptor) located at the end of the sensory
neurons in the skin (C-fibers).”
“When
this nociceptor is stimulated by too much capsaicin through repeated topical
application, the C-fiber is eventually depleted of the neurotransmitters that
send pain signals to the brain.”
“In
short, we hypersensitize the system and then desensitize it to temporarily
alleviate the pain caused by the shingles virus or other types of neurogenic
inflammation involving C-fibers.”
Though
it is possible to relieve pain by applying capsaicin cream to your skin, the
most common way to make contact with capsaicin is of course eating it.
“When
ingested, it has potential antioxidant, anticarcinogenic and
anti-obesogenic benefits,” said Professor Valérie Marcil, a researcher in the
Department of Nutrition at the University of Montreal.
“First
of all, capsaicin may affect the life cycle of cancer cells by promoting
apoptosis, the programmed death of cells.”
“This
is a mechanism that often does not work normally in cancer cells. They survive
and multiply, when they should have been destroyed by apoptosis.”
“But
there is evidence that capsaicin can help destroy some cancer cells. Also, the
capsaicin molecule is believed to have anti-obesogenic properties, as it
increases energy expenditure and the feeling of satiation.”
“But
capsaicin is not a panacea. And while its benefits have been demonstrated
in in vitro studies, its effectiveness in humans has
not been proven.”
“This
is the case with all nutrients,” she said.
“In
real life, you don’t eat nutrients, you eat food. And a food isn’t a drug. We
have to be careful in talking about the powers of food, since the actual
effects are often the result of a combination of factors.”
In
2021, a team of researchers from the Institute of Microbiology, Infectious
Diseases and Immunology, Charité, and the Humboldt-Universität zu Berlin provided evidence that capsaicin is a promising
complementary option for treating antibiotic-resistant bacterial infections.
While
it is not potent enough to replace antibiotics, it can reduce the quantity of
antibiotics needed to treat bacterial infections and decrease the risk of
developing resistance.
“This
is an avenue worth exploring,” said Professor Yves Brun, a microbiologist in
the Department of Microbiology, Infectious Diseases and Immunology at the
University of Montreal.
“Approaches
that combine two molecules have a number of advantages, since they can have a
synergistic effect.”
“Capsaicin
is well absorbed by the body and does not appear to be toxic, at least at the
ingested dose. However, we don’t know its mechanism of action, so that’s where
further research should start.”
“The
underlying molecular mechanisms must be better understood and the translation
of in vitro results into in vivo models will need to be validated in future
clinical trials.”
“But
whether the effects are antioxidant, anti-obesogenic, antibiotic or just
delightfully hot, there’s no reason to forego hot sauce!”
_____
Samuel
Füchtbauer et al. 2021. Antibacterial properties of capsaicin and
its derivatives and their potential to fight antibiotic resistance – A
literature survey. European Journal of Microbiology and Immunology 11
(1); doi: 10.1556/1886.2021.00003