Winter supplements, spring kills tigers.
In winter, the weather is cold, the heat consumption is large, the demand for qi and blood is large, and it is easy to lack qi and blood.
Nourish liver in spring, heart in summer, lung in autumn and kidney in winter. The kidney is not only a container for human vitality, but also a "fuel tank" for continuously supplying qi and blood needed by the body.
Therefore, winter is the golden season for tonic, and winter tonic can effectively enhance immunity.