Traditional Sichuan hotpot promises sensory delight at Beijing's Yi Jia Ren.(Photo provided to China Daily)
Some scientists have cautioned that some research may invite confusion about cause and effect.
Fang Yu, director of dietetics at the Peking University Cancer Hospital, told China Daily in 2015 that general well-being may play an important role in dietary choice.
"It's possible that some people eat more spicy food because they are inherently healthier than those who do not, especially in terms of their digestive systems," he said.
In fact, neither the US nor the China study determined what might cause the "positive association" between chili peppers and life expectancy. Researchers note that capsaicin - the principal component in chili peppers - is believed to play a role in cellular and molecular mechanisms that prevent obesity and modulate coronary blood flow. The latest study also notes that hot red peppers have antimicrobial properties that "may indirectly affect the host by altering the gut microbiota."
"Spicy food is extremely popular in China. That prompted us to conduct the study," says Lu Qi, the author of the earlier study, in an email exchange with China Daily in 2015.
