《黄帝内经·素问·六元正纪大论》
其气化致病时，司天热化所致宜用咸寒，年运清化所致宜用辛温，在泉燥化所致宜用酸温，这就是所谓适宜的药食性味。
灾九宫。燥化九，热化二，所谓正化日也。其化上苦小温，中咸温，下咸寒，所谓药食宜也。
When the human body is stricken with illness as a result of the influence of the climate, a salty and cold cure should be used if the cure is meant to counteract the effect of celestial change and heat, a spicy and warm cure is meant to counteract the effect of the annual movement and cold, and a sour and warm cure is meant to counteract the effect of subterranean change and dryness. This is what is meant by an appropriate medicinal or edible flavor.