FRUIT & VEGETABLE INTAKE AND EFFECTS IN SMOKERS

描述：（申请人的描述）吸烟已被 被认为是某些人类癌症和疾病的主要原因。 的 一个最有效的预防手段是消除烟草使用 从社会上，但这是目前一个不现实的目标。 是 据估计，近50%的美国成年人目前是吸烟者， 和前吸烟者;针对这种大的高风险的癌症预防策略 人口是必要的。 吸烟者的类胡萝卜素和维生素C、E较少 比不吸烟者，也许部分是由于增加清除和/或 抗氧化维生素的生物利用度降低。 抗氧化维生素是 身体抗氧化防御系统的一部分;吸烟者的水平较低 可能表明抗氧化防御较弱，这可能导致氧化DNA 可能的突变和癌症。 本研究的目的是 制定一项干预策略，使吸烟者能够吃五或 更多的水果和蔬菜（FV）/天（从两份）， 以有效地增加和维持他们的抗氧化维生素水平。 这应该会提高他们的抗氧化防御能力，降低癌症风险。 最近 研究结果表明，吸烟者摄入胡萝卜素可能有害， FV很少产生副作用。 此外，FV还含有其他种类的 癌症预防剂。 它可以是一种组合动作， 更大的保护。 这项为期四年的随机对照研究将重点关注抗氧化剂 FV的影响。 男性52例，女性52例（35-65岁，>15岁 一年内，每天抽一支烟）。 会有两个月的 磨合期和六个月的干预期。 干预组受试者 每周将获得至少35份FV和果汁， 干预期。 他们的每周FV摄入量将根据 提供和退回的金额。 对照组的受试者会吃他们平常吃的东西 在整个研究过程中。 在导入期， 各种类胡萝卜素，维生素C，E和A，两种潜在的氧化损伤 生物标志物，8-羟基脱氧鸟苷（主要标志物）和丙二醛 （第二标记物）和可替宁将在血液和/或尿液中测量。 在干预期间，将每月监测这些水平。 我们 一种假设是，与服用维生素片不同， 将吸烟者的叶酸摄入量增加到每天五份或更多（2000年 目标），从而大幅度和持续地提高了 抗氧化维生素，也许还有其他种类的癌症预防剂， 因此，氧化性DNA损伤和癌症风险可能会降低。 这项研究意义重大，因为其结果将直接适用于 吸烟者和戒烟者用于评估FV摄入量对癌症的充分性 预防，并制定有关饮食和 癌

DESCRIPTION: (Applicant's Description) Cigarette smoking has been implicated as a major cause of certain human cancers and diseases. The single most effective means of prevention would be to eliminate tobacco use from society; however, this is currently an unrealistic goal. It is estimated that nearly 50 percent of United States adults are current smokers and ex-smokers; a cancer prevention strategy targeting this large high-risk population is necessary. Smokers have less carotenoids and vitamins C and E than do nonsmokers, perhaps due in part to an increased clearance and/or a decreased bioavailability of antioxidant vitamins. Antioxidant vitamins are part of the body's antioxidant defense system; the lower levels in smokers may indicate a weaker antioxidant defense, which could lead to oxidative DNA damage and possibly mutation and cancer. The objective of this study is to develop an intervention strategy that will enable smokers to eat five or more servings of fruits and vegetables (FV)/day (up from two servings) in order to effectively increase and maintain their antioxidant vitamin levels. This should boost their antioxidant defense and reduce cancer risk. Recent findings indicate that intake of carotenes by smokers may be harmful, while FV seldom produce negative side effects. Also, FV contain other kinds of cancer preventive agents. It may be a combined action that provides a greater protection. This four-year randomized, controlled study will focus on the antioxidant effects of FV. Fifty-two male and 52 female smokers (35-65 years old, >15 cigarettes/day for >one year) will be recruited. There will be a two-month run-in and a six-month intervention period. The intervention group subjects will receive at least thirty-five servings of FV and juices weekly during the intervention period. Their weekly FV intake will be calculated from the amounts provided and returned. The control subjects will eat their usual diet throughout the study. During the run-in, the baseline levels of various carotenoids, vitamins C, E and A, two potential oxidative damage biomarkers, 8-hydroxydeoxyguanosine (primary marker) and malondialdehyde (secondary marker), and cotinine will be measured in blood and/or urine. These levels will be monitored monthly during the intervention period. Our hypothesis is that the intervention, unlike taking vitamin pills, will increase the FV intake by smokers to five or more servings/day (year 2000 goal), resulting in a significant and sustained increase in the levels of antioxidant vitamins and perhaps other kinds of cancer preventive agents as well; consequently, oxidative DNA damage and cancer risk may be reduced. This study is significant because the results will be directly applicable to smokers and ex-smokers for assessing the adequacy of FV intake for cancer prevention, and for formulating dietary guidelines regarding diet and cancer.