What is capsaicin?

Spicy food can cause a strong sensory reaction in many people, which can manifest itself in various ways, such as a burning sensation in the mouth, coughing or other physical reactions. This sensitivity to spicy food is caused, among other things, by the influence of capsaicin, the pungent ingredient found in many chili peppers. Capsaicin acts on certain pain receptors in the mouth, known as TRPV1 receptors, to trigger a sensation of heat or burning.

Sensitivity to spiciness and its consequences

Eating spicy food triggers a burning sensation in the mouth in many people due to the activation of TRPV1 receptors. These receptors, which respond to temperature and pain stimuli, are stimulated by capsaicin, the active ingredient in spicy foods. This stimulation results in the release of neurotransmitters such as substance P and calcitonin gene-related peptide (CGRP), which in turn trigger a pain response and increase the sensation of warmth. Such sensory reactions are a natural response by the body to potentially harmful stimuli and have a protective function, warning of possible tissue damage.

Did you know?

Spicy food can actually increase the release of endorphins in the body, leading to a "runner's high" that is often described as pleasant.

Influence on the cough reflex

In addition to pain perception, capsaicin can also trigger other physical reactions, such as the cough reflex. Capsaicin irritates the mucous membranes of the respiratory tract and can thus trigger the cough reflex to remove the stimulus from the body. This reaction is often perceived as unpleasant and can affect the quality of life, especially for people who are particularly sensitive to spicy foods. The cough reflex and other symptoms such as increased sweating or increased heart rate are direct reactions to the chemical properties of capsaicin and its effect on the nervous system.

What does genetics have to do with it?

The TRPV1 receptor is an important component of the body's pain and temperature perception system. It is located on the nerve cells of the oral and pharyngeal mucosa and reacts to pungent stimuli such as capsaicin. When capsaicin binds to the TRPV1 receptor, specific ion channels open, allowing calcium and sodium ions to flow into the nerve cell. This leads to a depolarization of the cell, which generates electrical signals. These signals are transmitted via the neural pathways to the brain, which interprets them as pain or burning.

The SNPs rs8065080, rs222741, rs224534 and rs222747 vary in the DNA sequence of the TRPV1 gene, resulting in different receptor variants. These genetic variations can alter the receptor's affinity for capsaicin. For some variants, such as rs8065080 and rs222747, the receptor shows increased sensitivity to capsaicin. This means that in people with these variants, the receptors react more strongly to capsaicin, leading to a stronger sensation of spiciness. In contrast, other variants, such as rs222741 and rs224534, can reduce the sensitivity of the receptor, resulting in a less intense reaction to spicy foods.