Think twice before adding that extra kick of chili sauce or chopped jalapeno to your meal. New research involving the University of South Australia shows a spicy diet could be linked to dementia.

A 15-year study of 4,582 Chinese adults aged over 55 found evidence of faster cognitive decline in those who consistently ate more than 50 grams of chili a day. Memory decline was even more significant if the chili lovers were slim.

The study, led by Dr Zumin Shi from Qatar University, showed that those who consumed in excess of 50 grams of chili a day had almost double the risk of memory decline and poor cognition.

“Chili consumption was found to be beneficial for body weight and blood pressure in our previous studies. However, in this study, we found adverse effects on cognition among older adults,” Dr Zumin says.

UniSA epidemiologist Dr Ming Li, one of five researchers involved in the study, says chili intake included both fresh and dried chili peppers but not sweet capsicum or black pepper.

“Chili is one of the most commonly used spices in the world and particularly popular in Asia compared to European countries,” Dr Li says. “In certain regions of China, such as Sichuan and Hunan, almost one in three adults consume spicy food every day.”

Capsaicin is the active component in chili which reportedly speeds up metabolism, fat loss, and inhibits vascular disorders, but this is the first longitudinal study to investigate the association between chili intake and cognitive function.

Those who ate a lot of chili had a lower income and body mass index (BMI) and were more physically active compared to non-consumers. Researchers say people of normal body weight may be more sensitive to chili intake than overweight people, hence the impact on memory and weight. Education levels may also play a role in cognitive decline and this link requires further research.

Additional information

The China Health and Nutrition Survey (CHNS) is an ongoing household-based cohort study conducted in nine provinces in China between 1989 and 2011. Cognitive screen tests were conducted among those aged 55 and above in regular intervals between 1991 to 2006. The participants were asked to recall a 10-word list, count backwards from 20, and do some basic subtractions.

It is estimated that dementia affects about 50 million people globally. In 2017, approximately 9.5 million Chinese adults aged 60 years and above had dementia.

The paper, “High chili intake and cognitive function among 4582 adults” is published in Nutrients.