OK, I just googled "what disease does Jet Li have" and find this; thyroid là giống như cái tuyến gì ở cổ họng mình đó;khi bị bệnh này dể bị lạnh, hay lên/xuống cân lắm. Opposite của hyperthyroidism là hypothyroidism - biết tiếng việt chết liền đó hahaha

hyperthyroidism
An overactive thyroid, or hyperthyroidism, causes changes in a person's metabolism and heart rate, among other symptoms, but is generally treatable with medications. Li was diagnosed in 2010. He kept his condition under control with medication, but it came back with a vengeance recently

http://www.dailymail.co.uk/tvshowbiz...e-thyroid.html