For the purpose of work， study， recreation and others， a lot of people usually have sleep liabilities （deliberately deduce the time for sleeping）. Although they will basically would choose to extend the sleep time during holidays to pay the "debt"， less sleep time for a long-term will still impact human metabolism.
　　Collaborative researches by many endocrinologists from Medical College in Qatar Angeles of Cornell University and the University of Bristol found that every 30 minutes of reduction in the time of sleep， after one year， will increase the risk of suffering from obesity by 17%， while the risk of insulin resistance will rise by 39%.
　　As known to all， insulin resistance is the leading cause of many serious endocrine disorders， such as type 2 diabetes， hyperlipidemia and even infertility culprit. With the finding of this study， the effects of lack of sleep for a long-term can be imagined. Therefore， we should correct the bad sleeping habits in a timely manner. After all， sleep liability is unlike the overdraft of credit card which is fine when you pay back as scheduled. .
　　（Respondents： Lu Yuanxi， medical science author）