Great Cold, the last solar term of winter, signifies the end of the old year and the beginning of the new. It has always been a crucial period for health preservation, as an old saying goes: "On Great Cold, guard against the wind and cold; drink Ginseng and Astragalus wine in the morning, and take Qi Ju Di Huang Wan in the evening," which illustrates its importance.
During Great Cold, the yin and yang energies in the universe begin to shift, with cold and warmth alternating in their dominance. The earliest classic of Chinese medicine, the "Huangdi Neijing·Suwen·Great Treatise on Regulating the Mind in the Four Seasons," states: "The three months of winter are called the season of storage. The water freezes and the earth cracks. Do not disturb the yang. Go to bed early and rise late, waiting for the sun. Keep your will as if it were hidden and secret, as if you had private intentions, as if you had gained something. Avoid cold and seek warmth. Do not cause the skin to perspire, lest the qi be rapidly depleted. This is the way to nourish storage in winter. To go against this injures the kidneys, leading to flaccidity and coldness in spring, and there will be little to support the growth of life." This passage brilliantly discusses methods for nourishing the spirit, daily routine, and diet, and introduces the principles of winter health for the human body based on the changes in nature. It tells us that winter is a season of extreme cold, withering vegetation, and dormant life. The body's yang energy also retreats and stores itself within, following the transformation of the natural world. Therefore, winter health preservation should follow the law of storage in nature, with the fundamental principle of protecting yang and conserving yin. Tang Jingyi, Department of Internal Medicine, Longhua Hospital, Shanghai
During this period, diseases of the cardiovascular and respiratory systems are prone to worsen and flare up. Statistics show that in January, which includes Great Cold, the incidence of myocardial infarction and stroke reaches its peak for the entire year. For some hypertensive patients with poor vascular elasticity, blood pressure fluctuations within a day tend to increase. Many patients with chronic obstructive pulmonary disease (commonly known as "old chronic bronchitis") can also easily trigger their chronic conditions if they are not careful.
For health preservation during Great Cold, the first priority is to care for the yang energy. 1. Pay attention to cold protection and warmth. Although it is not as brutally cold as around the Winter Solstice, it is still in the "Four Nines" period, and the saying "the three nines and four nines, walk on the ice" refers to this time around Great Cold. Even in the middle and lower reaches of the Yangtze River, cold waves can suddenly strike. The frail and elderly should ideally stay in a warm room, reduce going out, and avoid exposure to the wind and cold. When moving from indoors to outdoors, it is best to acclimate to the cold air in a hallway before going outside. 2. In terms of daily routine, go to bed early and rise late, following the characteristic of storage in winter, allowing the yang energy to fully recover through sleep. Before getting up and going out, it is advisable to drink a warm beverage like milk or soy milk to invigorate the spleen and harmonize the defensive qi. Before going to sleep at night, it is recommended to soak the feet in hot water or a medicinal decoction to unblock the blood vessels and harmonize the nutritive qi. 3. One should moderate sexual desire; even young people should not indulge in excessive sexual activity, as it can recklessly deplete the yuan qi of the kidneys. 4. During periods of abundant sunlight, moderately increase outdoor exercise to lay a good foundation for the rise and movement of yang energy after spring begins. However, exercise should not cause excessive sweating, as this could lead to the loss of yang energy along with sweat, causing damage instead.
Another key aspect of health preservation during Great Cold is nourishing yin. Generally, in the Yangtze River basin, precipitation decreases after the Winter Solstice. By the time of the Great Cold solar term a month later, it is the driest period. The average daytime air humidity is usually below 50%, and sometimes as low as 30% indoors. As the moisture in the air decreases, the body's yin fluids can also become insufficient. Many people with chronic respiratory conditions often experience a feeling of frequent coughing with phlegm, or thick, sticky phlegm that is hard to expel. Patients with cardiovascular diseases are more prone to increased blood viscosity. If vascular elasticity is reduced due to hypertension or age, it is even more likely to trigger dangerous situations like myocardial infarction, cerebral infarction, or cerebral hemorrhage.
1. Emphasize dietary conditioning. In winter, people usually eat "hot" foods to nourish yang. However, during Great Cold, it is not advisable to eat too many "hot" and drying foods like spicy or grilled items, lest they disturb the deficient fire. The most suitable food during this time is medicinal congee, which moistens the lungs and spleen and is easily absorbed. Duck meat, almonds, Ophiopogon japonicus, and wood ear fungus can both nourish yin and moisten the lungs. Ginseng, lamb, and dog meat in congee can both warm yang and replenish qi. Herbs like Angelica sinensis, jujube, goji berries, rehmannia root, and Astragalus root in congee have the effects of nourishing blood and moistening the lungs, relieving dryness, and promoting bowel movements. In addition, one should eat more yellow-green vegetables, such as carrots, rapeseed, and spinach. Regularly eating glutinous rice is also in line with the idea of nourishing the spleen and stomach.
2. In terms of daily routine, if the heating or air conditioning is often on indoors, in addition to ensuring regular ventilation, it is best to use a humidifier to increase air humidity. If using an electric blanket at night, try not to leave it on all night or set it too high.
3. Increase water intake as much as possible and do not wait until you are thirsty. Drink a glass of warm water before going to bed and after waking up. It is also a good idea to drink a little water before and after bathing to replenish lost fluids.
4. Pay attention to balancing work and rest. The period after New Year's Day and before the Spring Festival is the busiest time at work, plus the preparations for the New Year such as cleaning the house and buying goods, which can easily lead to fatigue and depletion of vital energy. Therefore, adequate rest and maintaining a calm mood are particularly important.
The famous Ming dynasty physician Zhang Jingyue said: "One who is good at supplementing yang must seek it within yin; then yang, with the aid of yin, can be inexhaustible in its generation. One who is good at supplementing yin must seek it within yang; then yin, with the support of yang, will have an unfailing source." The principles of health preservation during Great Cold are a perfect example of this.