在華人世界裡，「藥食同源」一直是社會文化思維的一環。由於食材與藥物皆來自於自然界，加上生活中「藥食同用」的情況不勝枚舉，因此中藥材總給人「有病治病，無病強身」的偏見；而藥食之間的未加區分，與使用宜忌的忽視，也造成藥食混用、誤用。本文詴圖以常見中藥材當歸爲例，釐清上述觀點，該藥材在歷代不僅被認爲是女科要藥、補血聖品，更經常用來治療疼痛，並與各種食材共同烹調，使用範圍相當廣泛。因該藥材既具有藥性，又常見於飲食，故考察其功效與使用背景對「藥食同源」文化與「藥食混用」的社會行爲探討應具有代表性的意義。依本文考證結果，「藥食同源」應是本草學發展的必經過程，而「藥食同用」乃至於「藥食混用」則是醫藥專業與社會文化行爲互相滲透的特殊現象。同時，當歸在早期的主治範圍相當廣泛，並非專用於治療女子疾病，亦不被歸類於食物。其具有開滯、溫陽、活血的藥性，且能藉由入血分而達補血之效，不僅能治療疼痛，只要符合該病機的病症皆能使用；至於隨處可見配合食物烹調的作爲，或許因爲當歸具有良好的氣味與口感，且使用劑量不大時不至於有明顯副作用而被強化，但對於醫藥專業人士來說，其使用的時機與界線是十分清楚的。

In the Chinese world, the concept of Chinese medicines and foods having the same origin has long been a part of social-cultural thinking. This is because foods and medicines all come from the natural world, and they are frequently used in tandem in our diet, but these concepts also lead to the expectation about the use of foods and medicinal herbs, that they can be both foodstuffs and cure. The disappointing lack of discrimination between foods and medicinal herbs and poor recognition of their actual characteristics regularly leads to misapplication in clinical use. This study attempts to take a common Chinese medicinal material-Tangkuei-as an example to explore the above-mentioned views. In all the past dynasties, this drug is considered not only being the key medicine for women's diseases, but also useful for enriching the blood. It often is used to treat pain and is cooked together with various kinds of foods. Because Tangkuei has therapeutic and dietary characteristics, making a study of it can enable us to gain a good idea about the underlying concepts of foods and Chinese medicines, and help us to see through the mist more clearly. This study shows that the concept of Chinese medicines and foods having the same origin is an inevitable outcome in the development of herbal pharmacology. However, using Chinese medicines and foods for both their medicinal and nutritive properties and misapplication of them are a common phenomenon in medical profession and social behavior. Moreover, the curative ambit of Tangkuei was quite extensive in early days; it was not particularly curative of women's diseases, and not sorted out from food. It can however cure "Qi" stagnation, and make it flow freely, warming the body and invigorating circulation of the blood. By entering the blood, Tangkuei can activate the blood and not merely treat the pain, it can remedy all the diseases conforming to a particular pathological mechanism. Although Tangkuei has good flavor and mild side effects when used in appropriate doses, to medical specialists its indications and contraindications are very clear, and should be complied with strictly.