Eating spicy food frequently is linked to a lower risk of death in a Chinese study, adding heat to the debate on whether people should eat chilies for health benefits.
The study involved 487,375 people aged 30 to 79 across China. Half were followed for 7.2 years. Over the study period, there were 20,224 deaths.
Those who said they ate spicy food once or twice a week showed a 10 per cent reduced overall risk of dying, compared with people who ate spicy foods less often.
"Compared with those who ate spicy foods less than once a week, those who consumed spicy foods six or seven days a week showed a 14 per cent relative risk reduction in total mortality," concluded Lu Qi, an associate professor at Harvard School of Public Health in Boston and his co-authors in Tuesday's online issue of The BMJ, formerly the British Medical Journal.
Fresh and dried chilies were the most commonly used of spices in the study.
It's impossible to draw a cause-and-effect inference between eating spicy food and deaths from cancer, heart disease and respiratory disease, the study's authors noted in calling for more studies on other populations around the world to test if the findings apply elsewhere.
Eating fresh chili peppers in Chinese cuisine may be correlated with other dietary habits and lifestyles, such as cooking with oil or eating more carbohydrate-rich foods like rice to relieve burning sensations, the researchers said.
'You are what you eat'
Prof. David Hoskin of the faculty of medicine at Dalhousie University in Halifax is a research scientist with an interest in the use of natural products to prevent and treat cancer.
"My advice would be that you definitely are what you eat," Hoskin said.
"If you like spices, definitely, add spices into the mix, with the proviso if you're eating a lot of spicy food, washing it down with a six-pack of beer is probably not a good idea."
In the study, the association was stronger among people who didn't drink alcohol.
It's possible consumption of spicy food was a marker for other unmeasured factors in the diet, such as drinking more green tea, which is also known to have health benefits.
One molecule in chili, called capsaicin, has been shown in lab studies on cell lines and animal models of cancer to reduce inflammation, Hoskin said. Reduced inflammation could prevent processes that lead to the development of some diseases.
Since spices, fruits and vegetables contain a variety of other phytochemicals, Hoskin suggested that what is most important is to enjoy a diet rich in many of them. For example, Chinese cuisine typically also includes a lot of ginger.
The only way to know for sure if spices like chili improve mortality risk would be to conduct a large randomized trial to modify diets, which is expensive to administer, Hoskin said.
Nita Forouhi from the University of Cambridge wrote a journal editorial titled "Consumption of hot spicy foods and mortality — is chili good for your health?" which accompanies the study.
"Should we encourage people to eat more chili?" Forouhi asked.
The "findings should be considered hypothesis generating, not definitive, and will undoubtedly encourage further work."
Nuit Regular is a chef at a Thai restaurant in Toronto. She wasn't surprised by the findings and thinks she knows what is behind them.
"When you eat spicy, it just [raises] your heart rate," Regular said. "The more you have it, it's just pumping out very good blood flow to all of your body."
The study was supported by the National Natural Science Foundation of China and National Key and Kadoorie Charitable Foundation in Hong Kong.