When new hairs are replaced,the color or pigment (色素) is also added to them.However,as one ages,this pigment becomes less and less available.At first,hairs will have a limited amount of pigment and they will appear to be grayish in color.In time,they will lose all of their pigment and will be white.Many things are known to cause graying,and genetics is a very powerful factor.If one of your parents turns gray at an early age,there is a good chance that you will too.Some people begin the graying process in high school,while others may be over the age of forty.
Constant worry and tension can have many harmful effects on the human body.It is a known fact that stressful times can cause one to suffer hair loss.It would make sense that if it can cause these problems,perhaps it also may contribute to graying.However,there is no sound evidence to support this.
On the other hand,many medical professionals believe that there may be a link between graying and a constant state of anxiety or tension.Does stress cause gray hair?There is no scientific evidence to support the theory,but it is best to avoid stressful situations.
【语篇解读】 压力会导致头发变白吗?许多人相信情况是这样的。本文从年龄和基因两方面谈了头发变白的原因,持续的压力和忧虑对于身体是有害的,可导致脱发。但是,究竟压力和头发变白之间是否有联系,目前尚无定论。
【2017届山东省长岛县高考英语一轮短文改错训练:7(含解析)】相关文章:
★ 【优化方案】2017届高考英语二轮复习全国卷Ⅱ规范练:6(含解析)
★ 湖南省岳阳市2014高考英语一轮单项选择训练题(2)及答案
★ 湖南省岳阳市2014高考英语一轮单项选择训练题(9)及答案
★ 湖南省汝城二中2014届高考英语一轮复习阅读训练 (6)
★ (全国通用)2014届高考英语一轮单元复习 限时强化训练十
★ 北京市2014高考英语一轮复习 练习手册(22)必修5 Unit 2 The United Kingdom(含解析)新人教版
★ 2017高考四川省广安市英语阅读理解一轮系列训练:5(含解析)
★ 重庆市2014高考英语阅读理解一轮(精品)训练题(10)附答案
★ 辽宁省辽阳市2014高考英语单项选择一轮(暑假)训练(10)附答案
★ 重庆市2014高考英语阅读理解一轮(精品)训练题(7)附答案
最新
2017-04-24
2017-04-24
2017-04-24
2017-04-24
2017-04-21
2017-04-21