Some chili peppers hide a quiet trick, they carry their own fire extinguisher. Researchers at Ohio State University have identified three natural molecules, capsianoside I, roseoside, and gingerglycolipid A, that soften the burn without changing the actual amount of capsaicin. The discovery reframes what heat really is on the tongue, not just a number, but a negotiation between capsaicin and compounds that modulate the body’s sensors.⁠ ⁠ For more than a century, Scoville Heat Units have been the yardstick for spice, calculated from capsaicin and dihydrocapsaicin. Yet when scientists equalized those levels across ten pepper cultivars and served them in the same base to trained tasters, the peppers did not feel equally hot. That mismatch pointed to hidden chemistry shaping sensation.⁠ ⁠ Careful lab work and taste tests clarified what was happening. In half tongue comparisons, where one side received pure capsaicin and the other capsaicin plus a candidate compound, panelists consistently ...