The study, published in the American Heart Association’s journal Hypertension, enrolled 606 Chinese adults and then determined their preferences for salty and spicy flavours. Researchers then linked those preferences to blood pressure.
"Previously, a pilot study found that trace amounts of capsaicin, the chemical that gives chilli peppers their pungent smell, enhanced the perception of food being salty," said senior study author Dr Zhiming Zhu, professor and director of the Department of Hypertension and Endocrinology at the Third Military Medical University in Chongqing, China. "We wanted to test whether this effect would also reduce salt consumption."
The researchers found that people with a preference for spicy food consumed less salt than those who least enjoyed spicy food. Individuals who eat more spicy food and less salt had 8 mm Hg lower systolic (upper) and 5mm Hg lower diastolic (bottom) blood pressure numbers.
Overlap in brain stimulation from salt and spice
Researchers also used imaging techniques to look at two regions of the participants' brains -- the insula and orbitofrontal cortex -- known to be involved in processing salty taste. They found that the areas stimulated by salt and spice overlapped and that spice further increased brain activity in areas activated by salt.
The study's authors said that this increased activity likely makes people more sensitive to salt so that they can enjoy food with less of it.
“Administration of capsaicin—the major spicy component of chilli pepper—enhanced the insula and OFC metabolic activity in response to high-salt stimuli, which reversed the salt intensity-dependent differences in the metabolism of the insula and OFC,” the researchers noted.
The researchers concluded: “Enjoyment of spicy foods may significantly reduce individual salt preference, daily salt intake, and blood pressure by modifying the neural processing of salty taste in the brain. Application of spicy flavor may be a promising behavioral intervention for reducing high salt intake and blood pressure.”
The National Basic Research Program of China and the National Natural Science Foundation of China funded the study.
Journal: Hypertension, November 2017, Volume 70, Issue 5
'Enjoyment of Spicy Flavor Enhances Central Salty-Taste Perception and Reduces Salt Intake and Blood Pressure'
https://doi.org/10.1161/HYPERTENSIONAHA.117.09950
Originally published: 31 October 2017
Co-authors: Qiang Li et al.