FOR WHAT

 NEW YORK (Reuters Health)

 

Thousands of cases of breast and colon cancers might be averted each year if people in colder climates raised their vitamin D levels, researchers estimate in a new report.

 

A number of studies have suggested that vitamin D may be important in cancer risk.

 

Much of this research is based on cancer rates at different latitudes of the globe; rates of breast, colon, and ovarian cancer, for example, are lower in sunnier regions of the world than in Northern climates where cold winters limit people's sun exposure.

 

Sunlight triggers the synthesis of vitamin D inhat  the skin, and people who get little sun exposure tend to have lower stores of the vitamin.

 

Complementing these studies are lab experiments showing that vitamin D helps prevent cancer cells from growing and spreading, as well as some clinical trals in which people given high doses of vitamin D showed lower cancer risks.

 

For the new study, researchers at the University of California used data on average wintertime blood levels of vitamin D and rates of breast and colon cancers in 15 countries.

 

They found that rates of the diseases tended to fall as average vitamin D levels climbed, according to their report in the journal Nutrition Reviews. The protective effect against colon cancer seemed to begin when blood levels of vitamin D reached 22 nanograms per milliliter (ng/mL); for breast cancer, that number was 32 ng/mL.

 

The average late-winter vitamin D Level among Americans is 15 to 18 ng/mL, according to the researchers.

 

They argue that, based on their data, if Americans were able to maintain a vitamin D level of at least 55 ng/mL, 60,000 cases of colon cancer and 85,000 cases of breast cancer could be prevented every year. Worldwide, those figures could be 250,000 and 350,000, respectively.

 

"This could be best achieved with a combination of diet, supplements, and short intervals -- 10 or 15 minutes a day -- in the sun," lead study author Dr. Cedric F. Garland, a cancer prevention specialist at the University of California San Diego, said in a statement.

 

No one is recommending that people bake in the sun to reach high vitamin D blood levels. According to Garland, spending a matter of minutes in the midday sun, with 40 persent of the skin exposed, is enough. For fair-skinned people, the researchers estimate that just three minutes in the sun can be adequate, while darker-skinned people may need about 15 minutes.

 

a lifeguard in Southern California, Garland said, may have little need for extra vitamin D to reach potentially protective levels, whereas a Northerner who tends to stay indoors much of the year may need much more.

 

Garland and his colleagues recommend that, in addition to modest sun exposure, adults get 2,000 IU of vitamin D per day -- which is the "tolerable upper intake level" set by U.S. health officials.

 

That limit exists because of the risk of vitamin D toxicity, which causes elevated calcium levels in the blood and problems such as nausea, weight loss, fatigue, and kidney dysfunction.

BY DR. JOHN BRIFFA

 

Back in April, I was interested to read some research, which assessed the relationship between vitamin D status and physical function in a group of elderly individuals.

 

Briefly, the results of this study found that lower vitamin D levels were found to be associated with lower muscular strength and physical function in both men and women. It occurred to me that getting out in the sun (sunlight stimulates vitamin D production in the skin) may be one simple and free way for individuals to maintain their physical powers in old age.

 

More recently, other research has come to light that suggests that vitamin D may have a crucial role to play in physical function for the elderly.

 

Researchers based in the Netherlands, assessed the relationship between blood vitamin D levels and physical performance in a group of 1,234 men and women aged 65 or older. The researchers not only measured physical performance, but also any decline in that performance over a three-year period.

 

In the analysis, the researchers compared the results obtained form individuals with vitamin D levels of less than 10 ng/ml (nanograms per milliliter of blood) and 10-20 ng/ml with the results of those whose levels were higher than 30 ng/ml. [A nanogram is one billionth of a gram]

 

The researchers found that physical performance was lower in the individuals with vitamin D levels of less than 10 and 10-20 ng/ml compared to those with levels greater than 30 ng/ml. The results of studies of this nature may be affected by other factors such as presence of chronic disease, body weight, and alcohol consumption. These factors were taken into account in the analysis in an attempt to isolate vitamin D levels as the only significant variable.

 

Having done this, they found that the sisk of physical function declining over the three-year period of the study was about twice in individuals with lower vitamin D levels compared with those with higher levels. The authors of this study concluded that blood levels of vitamin D of less than 20 ng/ml are associated with poorer physical performance and greater decline in physical performance in older men and women.

 

The results of this study add to the growing body of evidence linking vitamin D and improved health, including in elderly individuals. I sometimes wish that this sort of evidence got a bit more coverage. After all, sunlight exposure (the main source of vitamin D in the body) is not only health -promoting but free. I wonder if one of the reasons that this sort of research does not generaly get the ttention it deserves is because there's no money in it.

在飞机上吃过飞机上的早餐不久（早餐不好吃，还是晚餐比较好），飞机就着陆了， 入境时，海关的人查看了我的护照和I-20，然后微笑着对我说“You look under eighteen”，呵呵，心中窃喜~~~

 

不知道为什么还要检查一次行李，我的箱子又多又重，我根本拿不动，还好有人帮忙，但不是那些工作人员，那些检查行李的工作人员都好差劲，态度不好，也不乐于助人。搬行李的时候真是悔啊，干嘛弄得这么重，自己根本处理不来，可是用的时候却觉得，怎么不多带点啊，就省着买了。。。

 

第一天住在“Alhambra Inn”，优惠价$65再加税，住得还好，体会了时差的头痛。。。

自从我迷迷糊糊的拿到了美国签证，虽然还算有条理的进行准备，但是心里一直不认为这个梦想成真了，好象这是别人的事情，跟我没有关系；因为这样，所以一直并不感觉离别的伤感，每天见关系要好的朋友和同学，买自己喜欢的东西，反而很开心。

 

直到拿着我漂亮的四个行李箱，离开家门的那一刻开始，我真正感觉到了，原来要离开的那个人是我。路上没有兴奋，泪水不停从脸颊流下，“舍不得”这个词在这时被我演义的淋漓尽致。一直拉着HF的手，仿佛想要抓走什么。HF似乎比我更加伤感。。还没出家门的时候，妈妈打电话给我，哭了，唉，年纪越大越容易伤感，她本来说，我走她是不会哭的，现在知道了那是一句她说出来的大话，还好没有让她机场为我送行，她肯定哭的不得了！当然，虽然妈妈没送，但送我的HF也同样哭的不得了！XH和老公也来机场送行，有朋友真是件快乐的事情！

 

来到机场，回想起自己第一次坐飞机，就是在三年前的这个时候，那一次是从北京飞往西安的航班；由于小胖护照和签证的问题，让我根本没有机会兴奋，很是紧张，担心没办法登机。

 

这一次，是北京飞往洛杉矶的航班。我提前了1个半小时换登机牌，可工作人员却说没座位了。我心想，这太荒唐了，竟然飞机会卖超票！！！小姐让我等，好吧，我也只能等了。等啊等，工作人员说，由于昨日大雨，延误了航班，所以很多改机31号的，（那可是我也没有理由成为雨天的牺牲品啊~~~我没可能改日期的）。经过一番波折，有腾出3个座位，很不幸，我们有5个人，其中2个人没还是没座，我就是其中之一。怎么办？？国航的人苦口婆心的劝说我，让我晚一天飞，并给予赔偿，但是我没办法接受，我没有途径通知接机的人晚一天接啊！想到这些，再想到离别，没忍住对着航空公司的人就掉金豆子，她们本来还说我只能接受这个事实，但见状，立刻开始帮我协调，说服他人晚一天飞。那3个人里面，有一个人很好心把位子让给了我，也或许他并不想去美国，还能拿赔偿金，总之我很感谢他~~！接下来还是等啊等。我对HF说，还好妈妈没来，要是她遇到这种状况，一定会更着急的，我越来越觉得不让她来机场的这个做法太明智了！飞机起飞前的十几分钟我才换到登机牌，连行李都是HF给送的，所以也没跟他道别；我那时就是飞奔，一路跑，跑得都上不来气了，国航的人一直陪我办理所有的手续，否则我一定赶不上的。走上了飞机，我问机组人员“我是最后一个乘客吗？”，那人回答大精准，“您后面还有一位”；找知道这样，我还可以道个别再飞奔啊~~~

 

我乘坐的是机组专座，旁边有一个人脚非常臭，快要熏晕我了，但他人还不错，帮我递东西，还微笑，唉忍了吧。国航的晚餐我要了鸭肉饭，还不错，比我想象的好很多。睡觉的时候，空乘就把脚臭臭的那个人赶回到他的座位了，我也终于可以自由呼吸了。因为是机组专座，所以睡眠时间时，还给我拉了帘子，嘿嘿，偏得了！

写点什么呢？心中为什么会是乱的？没有头绪的？

妈妈晚上就会来了，想见她，又不想她来；是我长大了，还是害怕离别？

七年的生活，即将要换新妆了；年纪大了，不愿放手的就变多了

打理行囊，哪件该舍？哪件该留？