Association of dairy products,lactose, and calcium with the risk of ovarian cancer

Epidemiologic findings have been inconsistent regarding the association of dietary fat, dairy products, and lactose with risk of ovarian cancer. The authors conducted a case-control study in Hawaii and Los Angeles, California, to examine several dietary hypotheses regarding the etiology of ovarian cancer in a population with a broad range of dietary intakes. A total of 558 patients with ovarian cancer diagnosed in 1993-1999 and 607 controls were interviewed regarding their diet. Consumption of all dairy products, all types of milk, and low-fat milk, but not consumption of whole milk, was significantly inversely related to the odds of ovarian cancer. Similar inverse gradients in the odds ratios were obtained for intakes of lactose and calcium, although these nutrients were highly correlated (r = 0.77). The odds ratio for ovarian cancer was 0.46 (95% confidence interval: 0.27, 0.76) among women in the highest quartile of dietary calcium intake versus the lowest (p for trend = 0.0006). The significant dietary association was limited to dairy sources of calcium (p for trend = 0.003), although a nonsignificant inverse gradient in risk was also found in relation to calcium supplement intake. These results suggest that intake of low-fat milk, calcium, or lactose may reduce the risk of ovarian cancer.     

Calcium from dairy products, vitamin D intake, and blood pressure: the Tromso Study

BACKGROUND: The present epidemiologic study was conducted in Tromso, Northern Norway, in 1994-1995. OBJECTIVE: The objective was to evaluate the relation between calcium intake from dairy products and the intake of vitamin D on systolic and diastolic blood pressure. DESIGN: Subjects who were taking drugs for hypertension or heart disease, those taking calcium tablets, subjects reporting cardiovascular disease, and pregnant women were excluded, leaving 7543 men and 8053 women aged 25-69 y for analysis. Calcium and vitamin D intakes were calculated from a food-frequency questionnaire. RESULTS: After correction for age, body mass index, alcohol and coffee consumption, physical activity, cigarette smoking, and vitamin D intake, there was a significant linear decrease in systolic and diastolic blood pressure with increasing dairy calcium intake in both sexes (P < 0.05). However, the difference in blood pressure between subjects with the highest and those with the lowest calcium intake was 相似文献   

The influence of breakfast and dairy products on dietary calcium and vitamin D intake in postpubertal adolescents and young adults

Background: Given the importance of both calcium and vitamin D for bone health and the high prevalence of vitamin D from around the world, the present study aimed to evaluate calcium and vitamin D intake in a group of healthy Brazilian adolescents and young adults and to examine the influence of breakfast and dairy products in the total intake of these nutrients. Methods: One hundred and sixty adolescents and young adults, aged 16–20 years old, from a public school, participated in the present study. Three‐day dietary records were used to assess calcium and vitamin D intakes. Serum 25(OH)D levels were measured using a radioimmunoassay kit. The results were expressed as the mean (SD). Results: Only 3.8% of the subjects met the daily adequate intake recommendation for calcium, and none for vitamin D [682.2 (132.2) mg day^?1 and 124.0 (28.0) IU day^?1, respectively]. 25(OH)D serum levels were insufficient in 51.5% and deficient in 9.7% of the individuals [72.5 (22.3) nmol L^?1]. There was a significant positive correlation between dairy product intake with both calcium and vitamin D (r = 0.597 and r = 0.561, respectively; P = 0.000). Adolescents who ate breakfast had a significant higher mean calcium, vitamin D and dairy product intake than adolescents who did not report this meal. Conclusions: The majority of adolescents and young adults did not consume recommended intakes of calcium and vitamin D and also presented 25(OH)D insufficiency. The results indicate that a regular breakfast and the consumption of dairy products represent important strategies in improving calcium and vitamin D intake in the diet.     

Calcium, dairy products, and colorectal cancer

The relation between calcium intake, estimated from frequency of use of 29 food items, and colorectal cancer risk was analyzed using data from a case-control study conducted in Northern Italy. The study was conducted on 558 cases of colon cancer, 352 cases of rectal cancer, and 1,032 controls admitted to the hospital for acute, nonneoplastic, nondigestive tract disorders (39% with traumas, 17% nontraumatic orthopedic diseases, 25% acute surgical conditions, 19% other miscellaneous disorders). There was no appreciable trend in risk of colon or rectal cancer in relation to measures of calcium intake. The multivariate relative risk (adjusted for age, sex, education, area of residence, and consumption of selected indicator foods) for highest versus lowest quintile was 1.1 for colon and 1.0 for rectum. Likewise, there was no appreciable difference between cases and controls with reference to frequency of consumption of the two major calcium-containing foods (milk and cheese), with relative risk for the highest level of intake between 0.9 and 1.2. This study indicates that little or no protection on large bowel cancer risk is provided by dairy products or calcium intake in a range of 0.5-1.5 g per day.     

Evolution of the calcium paradigm: the relation between vitamin D, serum calcium and calcium absorption

Osteoporosis is the index disease for calcium deficiency, just as rickets/osteomalacia is the index disease for vitamin D deficiency, but there is considerable overlap between them. The common explanation for this overlap is that hypovitaminosis D causes malabsorption of calcium which then causes secondary hyperparathyroidism and is effectively the same thing as calcium deficiency. This paradigm is incorrect. Hypovitaminosis D causes secondary hyperparathyroidism at serum calcidiol levels lower than 60 nmol/L long before it causes malabsorption of calcium because serum calcitriol (which controls calcium absorption) is maintained until serum calcidiol falls below 20 nmol/L. This secondary hyperparathyroidism, probably due to loss of a "calcaemic" action of vitamin D on bone first described in 1957, destroys bone and explains why vitamin D insufficiency is a risk factor for osteoporosis. Vitamin D thus plays a central role in the maintenance of the serum (ionised) calcium, which is more important to the organism than the preservation of the skeleton. Bone is sacrificed when absorbed dietary calcium does not match excretion through the skin, kidneys and bowel which is why calcium deficiency causes osteoporosis in experimental animals and, by implication, in humans.     

Calcium,dairy products,and colorectal cancer

The relation between calcium intake, estimated from frequency of use of 29 food items, and colorectal cancer risk was analyzed using data from a case‐control study conducted in Northern Italy. The study was conducted on 558 cases of colon cancer, 352 cases of rectal cancer, and 1,032 controls admitted to the hospital for acute, nonneoplastic, nondigestive tract disorders (39% with traumas, 17% nontraumatic orthopedic diseases, 25% acute surgical conditions, 19% other miscellaneous disorders). There was no appreciable trend in risk of colon or rectal cancer in relation to measures of calcium intake. The multivariate relative risk (adjusted for age, sex, education, area of residence, and consumption of selected indicator foods) for highest versus’ lowest quintile was 1.1 for colon and 1.0 for rectum. Likewise, there was no appreciable difference between cases and controls with reference to frequency of consumption of the two major calcium‐containing foods (milk and cheese), with relative risk for the highest level of intake between 0.9 and 1.2. This study indicates that little or no protection on large bowel cancer risk is provided by dairy products or calcium intake in a range of 0.5–1.5 g per day.     

未绝经汉族女性维生素D受体基因与骨钙素

目的　了解维生素D受体 (VDR)基因的限制性内切酶 (BsmI)多态性在中国长春地区未绝经健康女性中的分布 ,并进一步探讨其与骨钙素 (BGP)的关系。方法　应用聚合酶链反应 限制性片段长度多态性解析 (PCR RFLPs)技术检测 186例在长春地区生活 10年以上无亲缘关系的未绝经健康汉族女性的VDR基因型 ,用放免法测血清BGP ,同时考察它们之间的关系。结果　VDR基因型分布频率为Bb基因型 2 3例 (12 4 % ) ,bb基因型 16 3例(87 6 % ) ,BB基因型缺如。b等位基因在本组人群中分布高达 93 8%。各型的BGP分别为 :Bb型 (4 5 95± 1 135 )μg/L ,bb型 (4 5 34± 1 2 6 7) μg/L。 2组基因型的BGP比较 ,无显著性差异 (P >0 0 5 )。 结论　长春地区未绝经汉族女性的VDR基因型与BGP之间无相关关系。     

孕产妇维生素D缺乏与早产的关系

维生素D是人体必需的一种营养素,具有广泛的生物学效应。妊娠会使孕妇体内激素水平和代谢状况发生改变,所需营养素明显增加,也是维生素D缺乏的一个高发阶段。维生素D缺乏可能是造成早产的危险因素之一。该文就孕产妇维生素D缺乏与早产的关系进行综述。     

绝经前合理应用维生素D和钙剂与绝经后妇女骨密度的关系

目的:调查绝经前后妇女的体成分与绝经年龄、身高及应用维生素D和钙剂后骨密度的关系。方法:采用1∶1配对设计方法,将196例妇女分为绝经期前未用维生素D和钙剂者和用维生素D和钙剂者两组,采用米尺和磅秤测量两组妇女的身高和体重,采用双能X线骨密度仪检测两组妇女的骨质疏松值,采用超声骨密度仪检测两组妇女的左侧跟骨的超声速度、骨硬度指数和低骨量。观察两族妇女体内骨密度指标。结果:绝经前后不同年龄组妇女体质指数、超声速度、骨硬度指数、低骨量及骨质疏松值比较差异有统计学意义(P<0.05)。应用维生素D和钙剂的妇女骨密度较未应用维生素D和钙剂的妇女同年龄组相比,骨质疏松值有所下降。结论:绝经前后妇女合理应用维生素D和钙剂安全、有效,可早期预防骨质疏松,值得推荐,特别适用于绝经后妇女。     

Calcium, vitamin D, and dairy product intake and prostate cancer risk: the Multiethnic Cohort Study

High intakes of calcium and dairy products have been suggested to be related to prostate cancer risk. Such associations were examined in the Multiethnic Cohort Study (1993-2002) among 82,483 men who completed a detailed quantitative food frequency questionnaire. During a mean follow-up of 8 years, 4,404 total cases of prostate cancer were identified. In Cox proportional hazards models, no association was found between calcium and vitamin D intake and total, advanced, or high-grade prostate cancer risk, whether for total intake, intake from foods, or intake from supplements, among all male participants or among nonusers of supplemental calcium. No association of calcium or vitamin D intake was seen across racial/ethnic groups. In analyses of food groups, dairy product and total milk consumption were not associated with prostate cancer risk. However, low-/nonfat milk was related to an increased risk and whole milk to a decreased risk of total prostate cancer; after stratification, these effects were limited to localized or low-grade tumors. Although the findings from this study do not support an association between the intakes of calcium and vitamin D and prostate cancer risk, they do suggest that an association with milk consumption may vary by fat content, particularly for early forms of this cancer.     

Nutrigenomics, vitamin D and cancer prevention

Although there is growing epidemiological, preclinical and clinical evidence suggesting that low vitamin D intake, exposure and/or status is associated with an increased risk of various types of cancer, the optimum amount needed remains controversial. Furthermore, there is evidence that a U- or J-shaped response curve exist between 25(OH)D and certain cancers. Increasing information about the impact of genetic variation, especially polymorphisms that influence absorption, transport, metabolism and associated molecular targets, should help clarify inconsistencies in the data regarding vitamin D's effect on cancer risk. Rather than focusing on the main effects of a few variants of these genes alone, future studies need to consider gene-nutrient or environmental interactions. Nutrigenomics should clarify who might benefit and be placed at risk because of vitamin D exposure.     

Intermittent high-dose vitamin D prophylaxis during infancy: effect on vitamin D metabolites, calcium, and phosphorus

In infants receiving intermittent high dose vitamin D prophylaxis (600,000 IU ergocalciferol per dose orally) every 3-5 mo, the serum concentrations of vitamin D metabolites, calcium (Ca), and phosphorus (P) were determined before and 2 wk after each dose. The 25-hydroxyvitamin D (OHD) concentrations increased to well above normal but the values returned to the normal range before each subsequent dose. The 24,25- and 25,26-dihydroxyvitamin D ([OH]2D) levels followed a pattern similar to that of 25-OHD, and both were closely related to the latter (r = 0.85, p less than 0.005, and r = 0.84, p less than 0.005, respectively). The 1,25-(OH)2D concentrations did not vary in a consistent pattern and remained largely within the normal range. All infants had normal Ca levels before the first dose but 14 infants (34%) later had one or both Ca values above the upper normal limit of 2.80 mmol/L (2.81-3.32 mmol/L), indicating that the vitamin D doses were excessive despite the lack of accumulative increases in serum vitamin D concentrations.     

Nectin-4与卵巢癌的关系及其意义

目的:检测Nectin-4在卵巢癌中的表达情况,分析其与卵巢癌临床病理参数之间的关系。方法:RT-PCR法检测30例卵巢癌、25例卵巢良性肿瘤和30例正常卵巢组织Nectin-4 mRNA表达;Western blotting法检测Nectin-4蛋白表达。结果:①Nectin-4 mRNA表达为卵巢癌组0.71±0.12,卵巢良性肿瘤组0.32±0.09、正常卵巢组0.30±0.09,卵巢癌组显著高于后两组,差异有统计学意义(P<0.01)。卵巢癌组织中,不同年龄、病理类型间比较,差异均无统计学意义(P>0.05);不同病理分化程度、手术病理分期、有无淋巴结转移比较,差异均有统计学意义(P<0.05)。②Nectin-4蛋白表达为卵巢癌组0.71±0.06、卵巢良性肿瘤组0.35±0.07、正常卵巢组0.32±0.07,卵巢癌组织明显高于卵巢良性肿瘤和正常卵巢组织,差异有统计学意义(P<0.01)。结论:卵巢癌存在Nectin-4过度表达,与其病理分化程度、手术病理分期及淋巴结转移有密切关系,提示Nectin-4参与调控卵巢癌发生及发展过程。     

Importance of calcium, vitamin D and vitamin K for osteoporosis prevention and treatment

Throughout the life cycle the skeleton requires optimum development and maintenance of its integrity to prevent fracture. Bones break because the loads placed on them exceed the ability of the bone to absorb the energy involved. It is now estimated that one in three women and one in twelve men aged >55 years will suffer from osteoporosis in their lifetime and at a cost in the UK of > 1.7 pounds x 10(9) per year. The pathogenesis of osteoporosis is multifactorial. Both the development of peak bone mass and the rate of bone loss are determined by key endogenous and exogenous factors. Ca supplements appear to be effective in reducing bone loss in women late post menopause (>5 years post menopause), particularly in those with low habitual Ca intake (<400 mg/d). In women early post menopause (<5 years post menopause) who are not vitamin D deficient, Ca supplementation has little effect on bone mineral density. However, supplementation with vitamin D and Ca has been shown to reduce fracture rates in the institutionalised elderly, but there remains controversy as to whether supplementation is effective in reducing fracture in free-living populations. Re-defining vitamin D requirements in the UK is needed since there is evidence of extensive hypovitaminosis D in the UK. Low vitamin D status is associated with an increased risk of falling and a variety of other health outcomes and is an area that requires urgent attention. The role of other micronutrients on bone remains to be fully defined, although there are promising data in the literature for a clear link between vitamin K nutrition and skeletal integrity, including fracture reduction.