Origins of Sambok and Historical Calendar Background
Sambok (三伏) is a concept originating from China’s Heavenly Stems and Earthly Branches (干支) calendar system, dividing the hottest period of the year into three sections. The third Geng day (庚日) after the Summer Solstice (夏至) marks Chobok (early heat), the fourth marks Jungbok (mid-heat), and the first Geng day after the Beginning of Autumn (立秋) marks Malbok (late heat). Geng (庚), one of the Ten Heavenly Stems (十干), corresponds to Metal (金) in the system, and in Five Elements theory, Metal symbolizes autumn’s cool energy. The name Bok (伏) originated because the sweltering Fire Qi (火氣) suppresses Metal Qi (金氣), causing vital energy to be ‘subdued (伏)’. This concept appeared in Chinese historical records since the Qin (秦) Dynasty and spread throughout the East Asian Chinese character culture sphere.
Sambok Customs and Cultural Establishment in the Korean Peninsula
Records confirming Sambok customs on the Korean peninsula trace back to the Goryeo Dynasty. During the Joseon Dynasty, rituals on Bok days became firmly established in both royal court and common society, and the Veritable Records of the Joseon Dynasty contain multiple accounts of the king distributing ice or food to his officials on Bok days. Among the common people, the custom of eating boiled chicken or dog soup to replenish energy depleted by intense heat spread across various regions.
At the heart of Bok day food culture lies the principle of ‘fighting heat with heat’ (以熱治熱). This idea of treating heat with heat originated from traditional Korean medicine’s theory of yin-yang (陰陽) balance, based on the logic of eating hot food to promote sweating and enhance the body’s thermal circulation. High-protein ingredients such as chicken, eel, and abalone became established as Bok day foods on the basis of this theoretical background.
In modern times, Samgyetang (ginseng chicken soup) became established as the representative dish of Bok days after the 20th century. As dog soup, which was primarily consumed through the Joseon Dynasty, fell out of favor with social change, Samgyetang made with chicken and ginseng took its place. Today, Bok days are recognized not so much as seasonal rituals but as a seasonal turning point for health management against summer heat, with consumption of tonifying foods concentrated around this period each year.
This content is excerpted from 2026 June Marketing Calendar — Complete Summary of June and July Season Issues. Check the marketing calendar that Soulpapa Marketing organizes monthly.
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Original Korean article: https://soulpapa.co.kr/2026/06/01/calendar-2026-06-717-%ea%b8%88-%ec%b4%88%eb%b3%b5-727-%ec%9b%94-%ec%a4%91%eb%b3%b5-%eb%b3%b4%ec%96%91-%ed%94%bc%ed%81%ac/
