When I was studying macrobiotic diet therapy, I said that we should eat food that grows within 31 miles (50 kilometers) of our vicinity. Food produced within this area is the best fit for our bodies. There is also a directional aspect to consider. Because the direction of energy movement in the Southern Hemisphere and the Northern Hemisphere is opposite, it is better to eat food produced in the same hemisphere.
As the saying goes, “One type of soil and water nourishes the people within its proximity.” That is why we often see people who are new to a place, whether foreign or just another location in the same country, experience some kind of discomfort.
The ancient Chinese believed that “heaven and man are intertwined as one,” and “human beings are born with the energy from the heaven and the earth and follow the law of the four seasons.” This means that the human body depends on the materials provided by the energy from heaven and the earth to survive, and at the same time, it must adapt to the regular changes of the four seasons—spring, summer, autumn, and winter—for it to flourish and grow.
Our bodies are connected to nature, conforming to the local water, soil, food, and climate. Therefore, if people want to maintain their health and live a healthy life, they must eat locally produced natural and seasonal food, coordinate with nature, and form their ecological microenvironment. In this way, no matter how the outside world changes, the healthy microenvironment inside the body can remain relatively stable.
From childhood to adulthood, I often heard the term “dang zao (at the right season)” from my elders or at market stalls, and gradually realized the real concept of “only eat what is in season.”
Confucius advocated for “only eat what is in season,” eating the right food according to different seasons and festivals. In the classic work of traditional Chinese medicine (TCM) theory “Huang Di Nei Jing,” there is also one famous saying, “prepare things according to seasons,” which sums up the idea to follow the laws of nature to prepare medicines and food. Medicines and food obtained in this way have all the essences and fragrances of heaven and earth, which is of good taste, and high nutritional value.
In the view of TCM, food, and medicine can only obtain the essence of heaven and earth when they are “in season,” that is when they grow and mature coinciding with the proper seasonal terms. If they are not in season, they will not have the characteristics of that particular season, and their health value will be reduced.
As early as the Zhou Dynasty more than 2,000 years ago, there was already a “Four Seasons Food List.” Animals possess different meat quality in different periods of growth. The so-called “Xiaomanhe crooked (clams) are thin and lame, the summer solstice crucian carp is empty, and the Dragon Boat Festival crabs are empty too.” All these sentiments talk about untimely food.
On the contrary, seafood and those reared from the rivers are completely different. Right before Ching Ming (early April), the saury bones are soft, and the river mussels have enough pulp; summer carp, shrimp, and the like are full of nutrients and taste nice.
There is also an interesting saying about seasonal diet: “Eat radish in winter and ginger in summer, and you don’t need a doctor’s prescription.”
Li Ke, a registered TCM practitioner in Hong Kong, explained that Chinese medicine believes that ginger is spicy and warm. It can activate perspiration to achieve the aim of driving away the evil qi on the body’s surface. Other benefits include warming the spleen and stomach, and the lungs to stop coughing. Radish is mild and cool in nature and has the functions of promoting qi and eliminating indigestion, relieving cough and reducing phlegm, moistening the lungs and promoting body fluid, clearing the heat and detoxification, and improving diuresis and laxative effects.
TCM found that most foods are either “cold” or “hot” in nature, and they further subdivide many common foods into three types: cold food, hot food, and warm and neutral food. When a person eats cold foods, they add a cooling effect to the body, while eating hot foods adds a warming effect. Therefore, being taken properly in the right proportion between the two can help achieve balance within the body.
Since ginger is warm and radish is cold, it would be like getting hotter when you eat ginger in summer and colder when you eat radish in winter.
Li Ke quoted the exposition in the “Huang Di Nei Jing” and said that in spring, the yang energy begins to rise; in summer, when everything prospers, it reaches its peak. When autumn approaches, the yang energy starts to recede when the temperature gets lower. By winter, all the yang energy moves and hides in the soil, with the frozen ground on top. As TCM believes that the human body and nature are interlinked, it is expected that the cycle of the human body follows that of Mother Nature.
TCM has found that all things or phenomena in nature have corresponding characteristics of yin and yang, in the same way that the earth and the sky, and cold and heat do. Yin and yang are opposites, but they are also mutually interdependent. When yin and yang are balanced, people feel healthy, energetic, and raring to go. And by then, all things big and small will be well coordinated and stable.
TCM believes that qi is the energy or vitality that constitutes life in the body, and TCM generally refers to the substances that replenish nutrients in the body as blood. Qi and blood are interdependent, flow throughout the whole body, nourish the organs and tissues, and maintain all vital activities within the human body.
In summer, both the qi and blood tend to flow outward, resulting in the pores opening. With this yang-qi overflow, those who remain inside get less robust. If you want to feel cooler during the hot season, you should eat more cold food, drink various iced drinks or take a cold shower, and the like, which will make your stomach cold. “Eating ginger in summer” is indeed one way of using the warmth and spiciness of ginger to disperse some of the coldness in the viscera to the body surface to counter the hot temperature. Doing so, it can make the body achieve a balance of yin and yang, making the whole body feel more comfortable.
On the other hand, in winter, as the yang energy retreats, the pores shrink, and the chances of sweating to dissipate heat are reduced. People often eat hot foods such as tonics or mutton to counter the cold, which is more likely to generate internal heat and indigestion. At this time, eating some cool radishes can evacuate part of the yang qi inside the body to the surface, which can help keep out the cold and help digestion.
People all over try to eat in a way that is close to the traditional concept.
In 1907, Imperial Japanese Army pharmacy supervisor Sagen Ishizuka, as the chairperson of the Macrobiotic Association, proposed “to maintain health with local basic food.” He believed that people should eat more seasonal food produced on the land in which they live.
In 1912, Army Cavalry Colonel Nishidugaku, one director of the Macrobiotic Association, simplified the theory of Ishizuka and proposed that “eating locally produced food will make the body healthy while eating foreign food will make the body worse.” Nishidugaku studied and borrowed the phrase “body and soil are inseparable” (body and the environment cannot be separated) from Buddhism for the promotion of his related theories.
A Canadian couple once tried to eat only food produced within 100 miles of their habitat for a year. After that, they wrote about their experience in a book published in 2007, “The 100-Mile Diet: A Year of Local Eating.”