维生素D缺乏和乳腺癌扩散的关系;预防的意义.doc

Vitamin D Deficiency Linked To Spread Of Breast Cancer; What It Means For Prevention维生素D缺乏和乳腺癌扩散的关系；预防的意义Mar 2, 2016 01:00 PMByLecia Bushak2016年3月2日 莱西亚 不沙克Stanford researchers found that vitamin D deficiency led to worse prognoses for mice with breast cancer, but they also warn of the dangers of taking too many supplements.斯坦福研究者发现，维生素D缺乏会导致乳腺癌患鼠的预后更糟糕，但他们同时也警告，服用过多补剂有危险。Vitamin D-deficient mice with breast cancer are more likely to experience a spread in tumor growth compared to mice who have enough of the vitamin,a newstudyout of Stanford University School of Medicine finds. The study suggests that maintaining vitamin D levels could act as a protective factor against cancer, a notion that has been investigated in past research.根据斯坦福大学医学院的一项新研究，维生素D缺乏的乳腺癌患鼠，与维生素充分的鼠相比，更有可能经历肿瘤生长扩散。该研究表明，将维生素D维持在一定水平可以作为抗癌保护因子，这是过去研究中发现的一个概念。The researchers linked vitamin D levels to the ID1 gene, which at high levels of expression is associated with breast cancer tumor growth. Past studies have shown that vitamin D is linked to inhibiting the expression of this gene, and that low vitamin D levels have been associated with more aggressive tumors.研究者把维生素D水平和ID1基因联系起来，ID1基因的高水平表达和乳腺癌肿瘤增长有关。过去的研究已显示，维生素D和抑制这种基因的表达有关系，且较低的维生素D水平和恶性肿瘤有关系。In the study, the researchers gathered mice with breast cancer into two groups: The first group was given a diet lacking vitamin D for 10 weeks, and the other was given a normal diet with adequate vitamin D. The mice who consumed a diet without vitamin D ended up developing tumors seven days sooner than the other group, and they also ended up growing larger tumors. To examine how this was happening, the researchers focused on ID1, which was expressed more in tumor cells when vitamin D was lacking in the diet.在该研究中，研究者将乳腺癌患鼠分成两组：第一组食用不含维生素D的膳食十周，另一组的正常饮食中含有充足的维生素D。结果是，食用的膳食中不含维生素D的老鼠的肿瘤发展速度比另一组要快7天，而且他们的肿瘤长得更大。为了找到原因，研究者们关注了ID1基因，当膳食中缺乏维生素D时，肿瘤细胞中的该基因表达会更多。This study isnt the first to analyze vitamin Ds link to cancer. Adequate levels of vitamin Dhave been shown to lower the risk of breast,prostate, andcolon cancers. But varying results among studies have made scientists cautious of touting the benefits of vitamin supplements, as they still technically havent been proven to work consistently.该研究并不是分析维生素D和癌症之间关系的第一项研究。充足的维生素D水平已被证明可以降低乳腺癌、前列腺癌和结肠癌风险。但是各项研究的各种不同结果已经令科学家们谨慎宣传补充维生素的好处，因为从技术上讲还未证明它们可以和谐作用。There are plenty ofcontradicting opinionsand studies on the efficacy of vitamin D supplements when it comes to treating or preventing health problems, and the current studys researchers are aware of them. They note thattaking vitamin D supplements often does more harm than good, especially if the person already has enough vitamin D. Its tough to determine how much a person needs, because sun exposure changes throughout the year, and everyone absorbs the vitamin from the suns UV raysdifferently based on where they live and their skin color. Too much vitamin D has been linked to kidney, heart, and other organ damage. This is perhaps why most researchers and theNational Cancer Institutecan agree that the evidence behind vitamin Ds link to cancer prevention is “inconclusive.”关于维生素D补充对治疗或预防健康问题的效果，有很多矛盾观点和研究，目前这项研究的研究者们也都有所了解。他们指出，服用维生素D补剂往往弊大于利，尤其是当这个人已经有充足的维生素D。很难确定一个人需要多少，因为全年的日照是变化着的，而且每个人根据他们所在地和皮肤颜色的不同，从太阳紫外线吸收维生素也不同。太多的维生素D会对肾脏、心脏和其他其他有害。这也可能是为什么多数研究者和美国国家癌症研究所同意维生素D和癌症预防的关系“不确定”。Regardless, it cant hurt to make sure you get a few minutes of sun every day, and take vitamin supplementsif your doctor deems them safe for you.Take steps to improve your vitamin D intake only if youve been diagnosed with a deficiency.无论如何，确保自己每天都晒几分钟太阳，且服用你的医生认为是安全用量的维生素补剂不会有害处。如果被诊断为维生素D缺乏，只需要逐步改善你的维生素D摄取量即可。“Although much more research needs to be done, research from our lab and others suggests that people at risk for breast cancer should know their vitamin D levels and take steps to correct any deficiencies,” Dr. Brian Feldman, assistant professor of pediat