Ever wondered why your mouth feels like it’s on fire after eating something spicy? It’s not just the food—there’s a chemical called capsaicin that’s behind that fiery sensation.

Capsaicin is a natural compound found in chili peppers. The more capsaicin a pepper has, the hotter it feels when you eat it. It’s thought that this chemical is used by plants as a defense mechanism to protect peppers from being eaten by animals, but that hasn’t stopped humans from willingly consuming them to experience that spicy sensation.

Why does capsaicin make our bodies feel like they’re burning? Our mouth contains many sensory neurons that detect various sensations such as taste, temperature, touch and pain. When we eat spicy food, capsaicin binds to specialized receptors called TRPV1 located at the ends of these sensory neurons. These receptors are spread out throughout the body. They help detect noxious (hazardous) heat, high acidity and even inflammatory pain.

When capsaicin binds to TRPV1 receptors, it triggers a chain reaction in the sensory neuron that generates an electrical signal. This signal travels along nerve fibers to the brain. The brain and nervous system interpret this signal as a sign that the body is overheating and trigger ways to cool down the body.

If you’ve eaten spicy food, you may already be familiar with the classic responses to overheating that help your body return to a normal temperature: sweating, increased heart rate and widening of the blood vessels (vasodilation).

But capsaicin doesn’t just bring the heat—surprisingly, it has pain-relieving properties too. Some topical creams or patches that contain capsaicin are used to treat nerve pain. In these cases, the capsaicin product is applied to the skin and targets the neurons directly below the skin. Studies show that capsaicin can “defunctionalize,” or turn off, these neurons after they bind to TRPV1. This is incredibly effective at reducing overall pain.

Unlike oral pain medications, topical capsaicin can treat pain without a lot of it absorbing into the bloodstream. This reduces the risk of side effects. Moreover, recent studies suggest that capsaicin patches are more effective for treating diabetes-related nerve pain (diabetic neuropathy) compared to lidocaine patches, which contains a topical anesthetic. However, it’s important to realize that capsaicin’s effectiveness can vary from person to person.

The next time you seek natural pain relief, consider embracing the heat and finding relief with capsaicin—nature’s spicy secret to soothing discomfort.