There is a folk saying: "Radish at bedtime, ginger at rise-time, no need for the doctor's prescription." This means that eating a bit of ginger in the morning and some radish at night is beneficial to one's health. Why should ginger and radish be eaten at different times of the day?
This is determined by their nature. Ginger is spicy and warm in nature. In the early morning, the body's Qi (vital energy) in the stomach needs to be raised and activated. Eating ginger can strengthen the spleen and warm the stomach, encouraging the Yang energy to rise. By night, the body's Qi should be in a state of Yang energy converging and Yin energy flourishing. Eating ginger at this time goes against this physiological rhythm. In contrast, radish is cool in nature, known to clear heat, reduce fire, and promote the descent of Qi to aid digestion. After a day of work, eating some radish can moisten the throat, aid digestion, clear the heat of deficiency and dryness, and be conducive to rest.
Why is there a folk saying that "eating ginger at night is like eating arsenic"? The ancients said: "Eating ginger in the morning is better than ginseng soup; eating ginger at night is like eating arsenic." The meaning is clear: ginger is beneficial in the morning and harmful at night.
Ginger is spicy and warm in nature, good at dispelling wind-cold, transforming phlegm, and stopping coughs. It also warms the middle to stop vomiting and has detoxifying properties. Clinically, it is often used to treat conditions like external contraction of wind-cold and stomach-cold with vomiting. Past generations called it the "holy medicine for those who vomit."
The ginger-processing method utilizes these properties of ginger, using ginger juice as an auxiliary material to process other medicines. This enhances their effects of transforming phlegm, stopping coughs, and lowering Qi to stop vomiting, while also reducing their toxic side effects. For example, raw bamboo shi is used to clear heat and transform phlegm; after being ginger-processed, its effect of lowering Qi to stop vomiting is enhanced. Houpo (magnolia bark) is spicy and can irritate the throat; through ginger-processing, its side effect of throat irritation can be eliminated, and its effect of harmonizing the middle and stomach can be enhanced. Huanglian (coptis) becomes less excessively bitter and cold after being ginger-processed, and becomes particularly effective for treating stomach-heat vomiting.
After eating ginger, one may feel a sensation of warmth in the body. This is because it causes blood vessels to dilate, speeds up blood circulation, and opens the pores. This not only carries away excess heat but also expels pathogens and cold from the body. When one has consumed cold foods, been drenched in rain, or stayed in an air-conditioned room for too long, eating ginger can promptly relieve the various discomforts caused by excessive cold in the body.
There is also another saying: "Eat radish in winter, eat ginger in summer," which suggests that ginger should be consumed with caution in autumn and winter. Such "warnings" also appear in ancient medical texts: "Within a year, do not eat ginger in autumn; within a day, do not eat ginger at night."