Put Lemon on Your Fish? Thank Humoral Theory

The ancient medical theory, which prescribed a balanced diet for better health, still holds surprising influence

The popular pairing of fish and lemon goes back millennia. Shutterstock

Western history, from ancient times to the present, is filled with references to the four humors. Sometimes maligned, sometimes revered, and—in the modern world, at least—often misunderstood, humoral theory is one of history’s most enduring medical practices.

The four humors have shown up in literature and theater, in medical textbooks, in visual art, and, perhaps surprisingly, on your cookbook shelf.

The Basics

Humoral medicine dates back to the ancient Greeks, and is based upon the interplay between temperature and moisture. It originated with Hippocrates in the fourth century B.C., and was later elaborated on by Galen and others.