视频文本

The educational materials presented here
今天展示的教育材料
were developed by students and faculty
是由爱荷华州立大学营养学
of the department of food science and human nutrition
和人体营养学系的
at Iowa State University.
学生和老师提供的
Funding for this project was provided by grants
该项目的资金由
from the American Cancer Society Mid West
美国中西部地区癌症协会
and the Lance Armstrong Foundation.
及兰斯，阿姆斯斯壮基金会提供
The materials are intended for educational use
这些材料仅用于教学
and are not meant to provide medical advice.
并非用以提供医疗指导
We welcome your feedback about these materials.
欢迎大家对这些材料做出反馈
Please use the evaluation survey link on the homepage
请用主页上提供的调查评价链接
to provide your comments and suggestions.
提交你们的评论和建议
Caffeine's role in tea, coffee and cancer.
咖啡因在茶，咖啡与癌症方面所起的作用
Caffeine is found in many beverages and foods.
许多饮料和食物都含有咖啡因
This chart compares the amount of caffeine
这个图表比较了咖啡因
found in coffee and tea.
在咖啡和茶中的含量
As you can see the coffee is significantly higher
可以看见咖啡所含的咖啡因
in caffeine content than tea.
要远远高于茶
The way coffee is prepared also affects the amount
冲制咖啡的方式也会影响
of coffee in the beverage. Black, white and green tea
咖啡因的含量，红茶，白茶和绿茶
contains measurable amounts of caffeine.
含有不少的咖啡因
This may be surprising to some people
有些人也许会因此感到吃惊
who may think that green tea is caffeine free.
因为他们觉得绿茶中不含咖啡因
Decaffeinated teas have very low amounts of caffeine
不含咖啡因的茶含有极少量的咖啡因
and are a good alternative if you are interested in
这种茶是个不错的选择，如果你想
limiting your caffeine intake.
控制咖啡因的摄入量的话
The caffeine content in brewed coffee averages
每杯煮咖啡含有的咖啡因
between 100 and 200 milligrams per cup
介于100到200毫克
while the amount in regular tea
但普通茶中的咖啡因含量在
ranges from 40 to 100 milligrams.
40到100毫克之间
This chart lists a variety of beverages, foods
这个图表列出了一系列饮料，食物
and medicine with their caffeine content.
及药物的咖啡因含量
Note that caffeine content is not required to
请注意，咖啡因含量是不允许
be included on the food label, so finding the amount
注明在食品商标上的，因此要知晓
of caffeine in a product may take some research.
某个产品咖啡因的含量需要做一些研究
There are several websites where this information
有一些网站上能够找到这类信息
can be found including those of the manufacturer
包括食品生产商
of the product and also the Mayo Clinic nutrition site.
梅约诊所(美国一家医院)的营养网站
Something that may be surprising
令人吃惊的是
is the amount of caffeine in 2 tablets
两片特效止痛片中咖啡因的含量
of extra strength Excedrin; this is about the amount
因为含量差不多相当于一杯咖啡中的含量
provided in a cup of coffee and is delivered in 2 pills.
但两片药就含有这么多咖啡因
Now that you have an idea of how much caffeine is
既然大家已经对咖啡因在
in some popular beverages and foods,
一些饮料和食物中的含量有所了解了
let's take a look at how caffeine affects the body;
我们一起来看看咖啡因对身体的影响
caffeine stimulates the central nervous system.
咖啡因能够刺激中枢神经系统
It makes you more alert and boosts energy.
可以提高人的警觉性，增加体能
For these reasons it is used in
因此咖啡因经常用于
many over the counter pain relievers
许多非处方止痛药
such as Excedrin Migraine.
例如一种叫埃克塞德林的止痛药
How much caffeine is considered safe?
多少咖啡因才算安全剂量呢
There is no standard for caffeine consumption
没有固定的标准
however a range of 500 to 600 milligrams per day
但是每天摄入500到600毫克的咖啡因
is considered to be safe.
属于安全范畴
This would be around 4 to 7 cups of strong coffee,
这就相当于4到7杯浓咖啡
3 to 4 grande Starbucks vanilla lattes,
3到4大杯星巴克的香草味拿铁
9 to 11 cans of mountain dew
9到11听激浪
or 6 to 8 small cans of red bull.
或者6到8小听红牛

视频及简介

视频简介：

本课程的目标是，向公众提供最新的有关营养方面的信息和话题，内容涵盖饮食因素对于癌症的影响作用，健康的饮食习惯，学校能提供的营养有哪些，咖啡因与癌症的联系，水果蔬菜与癌症预防等。通过本课程的学习，人们可以学习到健康的生活饮食习惯，在每天的饮食中防癌症于未然。