n. a characteristic of certain foods or stimulants said to cause emotional or physical reactions associated with temper, fever, passion, excess, or true heat. 

一種食物或刺激物的特性，據說能引起情緒或身體上的反應，與脾氣、發燒、情緒、過量或熱有關。

From Chinese culture and medicine. 

源自中醫

"Shanghuo（heatiness）" is a unique concept in traditional Chinese medicine.

“上火”是傳統中醫中一個特有的概念。

Traditional Chinese medicine categorises food as 涼 lèung (“cooling”), 熱氣 yiht hei (“warming”) and neutral – and practitioners use the nature of the foods to balance the body’s yin and yang.

傳統中醫把食物分為涼性，熱性和中性——醫生們則用這些食物的特性以平衡人體的陰陽。

TCM describes heaty foods as having the ability to warm and improve circulation, dispel cold and stimulate the body. When these foods are taken in excess, （yang is greater than yin, your body will generate too much heat）heatiness is caused, resulting in symptoms such as fever, sore throat, mouth ulcers, acne, excessive thirst, redness of the skin and irritability.

中醫認為，熱性食物具有保暖、促進血液循環、驅寒和激發身體的功能。當這些食物攝入過量（體內的陽壓過陰時，你的身體會產生過多的熱氣），會導致“上火”的現象，引發發燒、喉嚨痛、口腔潰瘍、痤瘡、極度口渴、皮膚發紅和易怒等癥狀。