People who eat spicy food more frequently as part of a daily diet have a lower risk of death and are less likely to die from certain conditions such as cancer, heart and respiratory diseases, suggests a new study published in The BMJ this week. 

This is an observational study so no definitive conclusions can be drawn about cause and effect, but the authors call for more research that may “lead to updated dietary recommendations and development of functional foods.”

Previous research has suggested the beneficial effects of spices and their bioactive ingredient, capsaicin, to include anti-obesity, antioxidant, anti-inflammation and anticancer properties. 

A team of Chinese researchers working for the China Kadoorie Biobank examined the association between consumption of spicy foods as part of a daily diet and the total risk and causes of death.

They undertook a prospective study of 487,375 participants, aged 30-79 years, included in the biobank . Participants were enrolled between 2004-2008 and followed up for morbidities and mortality. 

All participants completed a questionnaire about their general health, physical measurements, and consumption of spicy foods (never, almost never, only occasionally, 1 or 2 days a week, 3 to 5 days a week, or 6 or 7 days a week), and other dietary habits. 

Participants with a history of cancer, heart disease, and stroke, for example, were excluded from the study. 

During a median follow-up of 7.2 years, there were 11,820 deaths among men and 8,404 deaths among women. 

Participants who ate spicy foods almost every day had a 14% lower risk of death compared to those who consumed spicy foods less than once a week. The association was similar for both men and women. 

The association was even stronger in those who did not consume alcohol. 

A threshold of around 1 or 2 days a week of spicy food consumption was found, beyond which the risk of death did not decrease further.

 Frequent consumption of spicy foods was also linked to a lower risk of death caused by cancer, and ischaemic heart and respiratory system diseases.

The number of deaths from infections was small, and more significant for women than men, but the authors explain that information may have been limited and cannot rule out an association.  

Fresh and dried chilli peppers were the most commonly used types of spices in those who reported eating spicy foods weekly, and those who consumed fresh chilli tended to have a lower risk of death from cancer, ischaemic heart disease, and diabetes.

This suggests that some of the bioactive ingredients are likely to drive this association, the authors explain, adding that fresh chilli is richer in bioactive ingredients, including capsaicin, vitamin C, and other nutrients. But they caution against linking any of these ingredients in lowering the risk of death.

Those who consumed spicy foods almost daily were more likely to be rural residents, smoke, drink alcohol and consume more red meat, vegetables and fruits compared to those who consumed spicy foods 3 - 5 days a week or less. 

Should people eat spicy food to improve health? In an accompanying editorial, Nit G Forouhi from the University of Cambridge says: "It is too early to say, but the debate and the research interest are certainly hotting up."

She calls for more research to test whether these associations are the direct result of chilli intake or whether chilli is simply a marker for other beneficial, but unmeasured dietary components or lifestyle factors.