Kim Jin-ho's Water and Coffee Story Finding the 'Dignity of a Glass of Water' in the Wisdom of Heo Jun from the 'Donguibogam'

Some 400 years ago, Heo Jun, the Medical Sage of Joseon, began the opening section of the "Donguibogam" with 'water (水)'. This was because he viewed water not merely as a beverage to quench thirst, but as the most fundamental and important element in sustaining human life and maintaining health. Heo Jun categorized water into no fewer than 33 types based on its nature and source, subdividing its uses accordingly.

As time has passed into the modern era, the essential question about water continues to be explored. The recent attention paid by the medical and academic communities to 'water care' and discussions on functional water, as well as water's standing in modern food and beverage culture, follow the same trajectory as the question Heo Jun posed 400 years ago.

■ Three Kinds of 'Good Water' That Preserve Health According to the Donguibogam

Among the 33 types of water recorded in the "Donguibogam," three representative types that govern health and the vital energy of life are as follows:

⊙ Jeong-hwa-su (Pure Water): Well water drawn first at dawn. It has a mild nature, is free from toxicity, and was used to clarify the vital essence of body and mind and stabilize the nerves.

⊙ Ok-jeong-su (Jade Spring Water): Spring water flowing from mountain valleys where jade (玉) is found. It was regarded as the finest water, nourishing the body and abundant in mineral essence to aid longevity.

⊙ Gam-ro-su (Sweet Dew Water): Water that tastes as sweet as dew and has a mild nature, said to be effective in benefiting the body's water balance and calming the mind.

In this way, our ancestors already deeply understood how subtle differences in water's source and condition affected the human body.

■ Modern Medicine's Focus on 'Senior Water Care' and Functional Water

This classical wisdom is being reinterpreted in modern medicine and public health. A prime example is 'Senior Water Care' proposed by Dr. Lee Gyou-jae, a leading authority in water research.

As people age, the water content ratio in the human body naturally decreases, and the sense of thirst becomes duller, making individuals susceptible to chronic dehydration. Modern water care goes beyond simply drinking clean water (hygiene) and emphasizes healthy habits that maintain the body's homeostasis and support vitality by appropriately consuming 'functional water' that takes into account absorption rates and mineral balance within the body.

Rather than being a concept that replaces specific medical treatment, it has established itself as a key pillar of everyday health management that prevents disease and enhances quality of life through proper water intake.

■ The Art of Taste Determined by Water's Minerals, Expanded into Coffee Culture

Interest in water's effects on health now naturally extends to daily food and beverage culture, particularly in the realm of coffee.

More than 98% of a cup of coffee is water. No matter how excellent the quality of the beans and roasting may be, the extraction rate of coffee compounds and the entire spectrum of flavor changes completely depending on the mineral composition (ratios of calcium, magnesium, etc.) and characteristics of the water used for extraction.

'Kim Beom-yeon Coffee' in Seoul is a representative space actively practicing this philosophy of water on-site. Rather than stopping at sourcing good beans, it researches what water best brings out the coffee's inherent flavor and shares that experience with customers. By intuitively conveying how water's functionality and mineral balance transform the aroma and taste of a cup of coffee, it communicates the dignity of beverages created by good water, transcending mere consumption.

■ How a Glass of Water Drunk Daily Changes the Value of Life

The value of good water that Heo Jun emphasized 400 years ago, the water care that modern medicine espouses, and the mineral story of water contained in a cup of coffee all converge into one message:

“The glass of water we drink thoughtlessly each day changes our health and determines the dignity of our daily lives.”

Ultimately, the foundation of a healthy life and rich taste always lies in the right choice of water. This is precisely the reason we must once again reflect on the meaning of the glass of water we drink today.