Young and middle-aged Chinese are worried about their health, showed a survey that cited stress, long working hours and difficulty in sleeping as the biggest sources of health concerns. The survey showed that 66.8 per cent of young and middle-aged Chinese believe their health is poor. A little over 44 per cent of respondents said they feel fatigued, according to a report by Insight China, an imprint of Qiushi, the Chinese Communist Party magazine.