Excessive weightlessness may trigger sudden death. In the case of heart disease such as cardiac decompensation, congenital heart disease, or overwork, excessive weightlessness may trigger sudden death. In the case of cerebral aneurysm, sudden weightlessness may lead to cerebral hemorrhage caused by rupture of cerebral blood vessels. This condition is usually characterized by severe headache, vomiting, weakness of one limb and slurred speech, which may also be life-threatening. Other than that, if weightlessness occurs occasionally, it is generally not life-threatening for normal people. If there are other symptoms of physical discomfort when weightlessness occurs, it is important to seek medical attention in a timely manner and follow the doctor’s instructions for checkups and treatments so as not to miss out on the condition.