Dietary omega-6/omega-3 fatty acids and risk of prostate cancer; Is there any potential interaction by organophosphate insecticides among the agricultural health study population.

BACKGROUND: In the United States (US), the average annual increase in the incidence of prostate cancer (PCa) has been 0.5% between 2013 and 2017. Although some modifiable factors have been identified as the risk factors for PCa, the effect of lower ratio of omega-6 to omega-3 fatty acids intake (N-6/N-3) remains unknown. Previous studies of the Agricultural Health Study (AHS) reported a significant positive association between PCa and selected organophosphate pesticides (OPs) including terbufos and fonofos. OBJECTIVE: The aim of this study was to evaluate the association between N-6/N-3 and PCa and any interaction between N-6/N-3 and 2 selected OPs (i.e., terbufos and fonofos) exposure. DESIGN AND PARTICIPANTS: This case-control study, nested within a prospective cohort study, was conducted on a subgroup of the AHS population (1193 PCa cases and 14,872 controls) who returned their dietary questionnaire between 1999 and 2003 MAIN OUTCOME MEASURES: PCa was coded based on the International Classification of Diseases of Oncology (ICD-O-3) definitions and obtained from the statewide cancer registries of Iowa (2003-2017) and North Carolina (2003-2014). STATISTICAL ANALYSIS: Multivariate logistic regression analysis was applied to obtain the odds ratios adjusted (aORs) for age at dietary assessment (years), race/ethnicity (white, African American, other), physical activity (hours/week), smoking (yes/no), terbufos (yes/no), fonofos (yes/no), diabetes, lycopene intake (milligrams/day), family history of PCa, and the interaction of N-6/N-3 with age, terbufos and fonofos. Pesticide exposure was assessed by self-administrated questionnaires collecting data on ever/never use of mentioned pesticides during lifetime as a yes/no variable. Assessing the P value for the interaction between pesticides and N-6/N-3, we used the continuous variable of "intensity adjusted cumulative exposure" to terbufos and fonofos. This exposure score was based on duration, intensity and frequency of exposure. We also conducted a stratified regression analysis by quartiles of age. RESULTS: Relative to the highest N-6/N-3 quartile, the lowest quartile was significantly associated with a decreased risk of PCa (aOR=0.61, 95% CI: 0.41-0.90), and quartile-specific aORs decreased toward the lowest quartile (Ptrend=<0.01). Based on the age-stratified analysis, the protective effect was only significant for the lowest quartile of N-6/N-3 among those aged between 48 and 55 years old (aORs=0.97, 95% CI, 0.45-0.55). Among those who were exposed to terbufos (ever exposure reported as yes in the self-report questionnaires), lower quartiles of N-6/N-3 were protective albeit nonsignificant (aORs: 0.86, 0.92, 0.91 in quartiles 1,2, and 3, respectively). No meaningful findings were observed for fonofos and N-6/N-3 interaction. CONCLUSION: Findings showed that lower N-6/N-3 may decrease risk of PCa among farmers. However, no significant interaction was found between selected organophosphate pesticides and N-6/N-3.

Measuring biopsychosocial risk for back pain disability in chiropractic patients using the STarT back screening tool: a cross-sectional survey.

Background: The Keele STarT Back Screening Tool (SBT), a 9-item questionnaire, screens for pain, physical functioning, fear-avoidance beliefs, catastrophizing, anxious thoughts, low mood, and bothersomeness in persons with back pain. SBT scores designate low, medium, or high risk for developing persistent disabling back pain. The primary study aim was to report the prevalence of SBT-calculated risk for back pain disability in US patients seeking chiropractic care. Methods: The SBT questionnaire was administered to patients ≥18 years in 3 Chiropractic College outpatient teaching clinics in Iowa and Illinois (May 2017). Descriptive statistics were used to analyze respondent characteristics and prevalence of SBT-calculated risk subgroups. Binary logistic regression analysis was used to examine the relationship between respondent characteristics and SBT scores (including psychological subscores). Results: Of 550 respondents, 496 completed the SBT; 392 (79%) scored low-risk, 81 (16%) medium-risk, and 23 (5%) high-risk. Mean (SD) age was 44.8 (15.9), 56.9% were female, 88.2% white, 62.6% employed, mean current pain was 2.9 (2.1) out of 10, and 62% reported symptom duration > 3 months. Eighteen percent of respondents reported anxious thoughts, 32% low mood, 41% ≥ 1 and 21% ≥ 3 SBT psychological risk factors. Respondents reporting higher average pain (OR = 1.8 [1.4, 2.3]) and pain severity (OR = 1.3 [1.0 to 1.6]) were more likely to score with medium or high risk. Respondents reporting mid back versus low back pain (OR = 0.2 [0.1, 0.7]), and those employed less than full-time versus full-time (0.2 [01, 0.5]) were less likely to score with medium or high risk. Respondents reporting higher average pain were more likely to report ≥1 psychological factor (OR = 1.8 [1.5, 2.0]). Respondents employed part-time were less likely to report ≥1 psychological factor than those employed full-time (OR = 0.4 [0.2, 0.7]). Conclusion: The sample surveyed was less likely to score with medium or high risk for back pain disability than previous samples studied, perhaps due to differences in study design and sample characteristics. Rates of low mood and anxious thoughts indicate a need for future research to explore psychological factors among persons seeking chiropractic care.

Cluster-Randomized Trial to Evaluate a Centralized Clinical Pharmacy Service in Private Family Medicine Offices.

BACKGROUND: The use of clinical pharmacists in primary care has improved the control of several chronic cardiovascular conditions. However, many private physician practices lack the resources to implement team-based care with pharmacists. The purpose of this study was to evaluate whether a centralized, remote, clinical pharmacy service could improve guideline adherence and secondary measures of cardiovascular risk in primary care offices in rural and small communities. METHODS AND RESULTS: This study was a prospective trial in 12 family medicine offices cluster randomized to either the intervention or usual care. The intervention was delivered for 12 months, and subjects had research visits at baseline and 12 months. The primary outcome was adherence to guidelines, and secondary outcomes included changes in key cardiovascular risk factors and preventative health measures. We enrolled 302 subjects. There was no improvement in the Guideline Advantage score from baseline to 12 months in the control group (64.7% versus 63.1%, respectively; P=0.21). There was a statistically significant improvement in the intervention group from 63.3% at baseline to 67.8% at 12 months (P=0.02). The estimated benefit of the intervention was 5.0%±2.4% (95% confidence interval=-0.5% to 10.4%; P=0.07). Several criteria were significantly better for intervention subjects, including appropriate statin therapy (P<0.001), body mass index, screening (P<0.001), and alcohol screening (P<0.001). Only 13.7% of subjects with diabetes mellitus had hemoglobin A1c at goal at baseline, and this increased to 30.8% and 21.0% in the intervention and control group, respectively, at 12 months (P=0.10). CONCLUSIONS: The centralized, remote pharmacist intervention was successfully implemented. The improvements in outcomes were modest, in part because of higher than expected baseline guideline adherence. Future studies of this model should focus on patients with uncontrolled conditions at high risk for cardiovascular events. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT 01983813.

Treatment history and antimicrobial susceptibility results for Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni isolates from bovine respiratory disease cases submitted to the Iowa State University Veterinary Diagnostic Laboratory from 2013 to 2015.

Bovine respiratory disease is the most costly disease facing the cattle industry. Increasing resistance to antimicrobial treatment has been presented as a significant contributing factor, often through summarized susceptibility testing data. We assessed the relationship between previous antimicrobial treatment and antimicrobial susceptibility results from isolates of Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni cultured from bovine respiratory cases submitted to the Iowa State University Veterinary Diagnostic Laboratory from 2013 to 2015. Antimicrobial susceptibility data from 1,251 bacterial isolates were included for analysis. More bacterial isolates from cattle that received antimicrobial treatment showed resistance compared to isolates from untreated cattle, and the percentage of resistant isolates increased as the number of antimicrobial treatments increased. Resistance to enrofloxacin, spectinomycin, tilmicosin, and tulathromycin was present in >75% of M. haemolytica isolates from cattle that had received 3 or more antimicrobial treatments; resistance to each of those 4 antimicrobials was present in ≤10% of M. haemolytica isolates from untreated cattle. Similar but less dramatic trends were apparent for isolates of P. multocida and H. somni. The percentage of multi-drug resistant bacterial isolates also increased with the number of treatments. Results of our study suggest that previous antimicrobial treatment may have a profound effect on antimicrobial susceptibility testing. Summarized susceptibility results from diagnostic laboratories should not be used to make generalized statements regarding trends in antimicrobial resistance without providing context regarding antimicrobial treatment history.

The Modern Metabolic Stone Evaluation in Children.

OBJECTIVE: To evaluate metabolic abnormalities in a contemporary pediatric population after their first stone episode. The incidence of pediatric nephrolithiasis is increasing and therefore the etiologies contributing to today's pediatric stone formation may also be changing. MATERIALS AND METHODS: A retrospective review of all consecutive children presenting after their first kidney stone between 2000 and 2014 was performed. We compared demographic data, serum chemistry results, and 24-hour urine results and treatments. RESULTS: One hundred thirteen children with a mean age of 11 years (5 months to 18 years) who presented with their first kidney stone episode between 2000 and 2014 were evaluated. Sixteen patients (14%) were found to have an underlying genetic or systemic disease. Overall, there was a low rate of serum chemistry abnormalities. The most common abnormalities found within the 24-hour urine evaluation included low urine volume (89%) and hypocitraturia (68%). Hypercalciuria occurred rarely (11%). CONCLUSION: We identified a low rate of underlying genetic or systemic diseases contributing to modern pediatric stone presentation and an increased proportion of idiopathic stones. Our study differs from historical findings by identifying a low rate of hypercalciuria and a high rate of low urine volume and hypocitraturia, suggestive of changing metabolic abnormalities contributing to modern pediatric stone disease.

Radon Testing: Community Engagement By a Rural Family Medicine Office.

OBJECTIVE: Iowa has the highest average radon concentrations in the nation, with an estimated 400 radon-induced lung cancer deaths each year. Radon is the second leading cause of lung cancer death overall. The objectives of this study were (1) to educate the population attending a family medicine office about the dangers of radon, (2) to encourage homeowners to test for radon, (3) to work with the community to identify resources for mitigation, and (4) to assess the utility of working with a local family medicine office as a model that could be adopted for other communities with high home radon concentrations. METHODS: Participants obtained a US Environmental Protection Agency-certified activated charcoal short-term radon kit through their primary care office or by attending a seminar held by their medical office. Participants completed a short investigator-developed questionnaire about their home, heating, and demographics. RESULTS: Of 746 radon kits handed out, 378 valid results (51%) were received, of which 351 questionnaires could be matched to the kit results. The mean radon result was 10.0 pCi/L (standard deviation, 8.5 pCi/L). A radon result of 4 pCi/L or higher, the Environmental Protection Agency action level for mitigation, was found in 81% of homes (n = 285). CONCLUSIONS: Four of 5 homes tested had elevated radon levels. This family medicine office/university collaborative educational model could be useful for educating patients about other environmental dangers.

A cluster of lead poisoning among consumers of Ayurvedic medicine.

BACKGROUND: Use of alternative medications and herbal remedies is widespread in the United States and across the globe. These traditional medications can be contaminated with toxic metals. Despite several case reports of poisoning from such contamination, the epidemiological data are still limited. OBJECTIVES: To report on a cluster of lead and mercury toxicity cases in 2011 among a community of adherents of traditional medical practice of Ayurveda. METHODS: Adherents of Ayurveda were offered heavy metals screening following the identification of the index case. RESULTS: Forty-six of 115 participants (40%) had elevated blood lead levels (BLLs) of 10 µg/dl or above, with 9.6% of BLLs at or above 50 µg/dl. CONCLUSIONS: This is the largest cluster of lead and mercury toxicity following use of Ayurvedic supplements described in the literature in the US. Contamination of herbal products is a public health issue of global significance. There are few regulations addressing contamination of "natural" products or supplements.

Employing resource allocation modeling to inform HIV prevention planning for the state of Iowa.

In fiscal year (FY) 2012, the Centers for Disease Control and Prevention (CDC) reallocated their HIV prevention funding to U.S. states, territories, and some cities so as to be more highly correlated with 2008 HIV prevalence. A jurisdiction's HIV prevention funding could drop as low as $750,000 for FY 2016. Iowa was one state that experienced a substantial funding drop, and it chose to undertake a mathematical modeling exercise to inform the following questions: (a) Given current HIV prevention funding for the state, what is the optimal allocation of resources to maximize infections averted? (b) With this "optimal" resource allocation, how many (and what percentage of) HIV infections in the state can be averted? (c) Is the optimal resource allocation sufficient to achieve the National HIV/AIDS Strategy goal of 25% reduction in HIV incidence? and (d) With the "optimal" resource allocation, is the return on the investment such that it might be considered cost-effective? Here, we describe the results of the policy analysis, and the uses of the results.

Interaction of nitrate and folate on the risk of breast cancer among postmenopausal women.

Ingested nitrate can be endogenously reduced to nitrite, which may form N-nitroso compounds, known potent carcinogens. However, some studies have reported no or inverse associations between dietary nitrate intake and cancer risk. These associations may be confounded by a protective effect of folate, which plays a vital role in DNA repair. We evaluated the interaction of dietary and water nitrate intake with total folate intake on breast cancer risk in the Iowa Women's Health Study. Dietary intake was assessed at study baseline. Nitrate intake from public water was assessed using a historical database on Iowa municipal water supplies. After baseline exclusions, 34,388 postmenopausal women and 2,875 incident breast cancers were included. Overall, neither dietary nor water nitrate was associated with breast cancer risk. Among those with folate intake ≥400 µg/day, breast cancer risk was significantly increased in public water users with the highest nitrate quintile (HR = 1.40, 95% CI = 1.05-1.87) and private well users (HR = 1.38, 95% CI = 1.05-1.82) compared to public water users with the lowest nitrate quintile; in contrast, there was no association among those with lower folate intake. Our findings do not support a previous report of increased risk of breast cancer among individuals with high dietary nitrate but low folate intake.

Dietary supplements and mortality rate in older women: the Iowa Women's Health Study.

BACKGROUND: Although dietary supplements are commonly taken to prevent chronic disease, the long-term health consequences of many compounds are unknown. METHODS: We assessed the use of vitamin and mineral supplements in relation to total mortality in 38,772 older women in the Iowa Women's Health Study; mean age was 61.6 years at baseline in 1986. Supplement use was self-reported in 1986, 1997, and 2004. Through December 31, 2008, a total of 15,594 deaths (40.2%) were identified through the State Health Registry of Iowa and the National Death Index. RESULTS: In multivariable adjusted proportional hazards regression models, the use of multivitamins (hazard ratio, 1.06; 95% CI, 1.02-1.10; absolute risk increase, 2.4%), vitamin B(6) (1.10; 1.01-1.21; 4.1%), folic acid (1.15; 1.00-1.32; 5.9%), iron (1.10; 1.03-1.17; 3.9%), magnesium (1.08; 1.01-1.15; 3.6%), zinc (1.08; 1.01-1.15; 3.0%), and copper (1.45; 1.20-1.75; 18.0%) were associated with increased risk of total mortality when compared with corresponding nonuse. Use of calcium was inversely related (hazard ratio, 0.91; 95% confidence interval, 0.88-0.94; absolute risk reduction, 3.8%). Findings for iron and calcium were replicated in separate, shorter-term analyses (10-year, 6-year, and 4-year follow-up), each with approximately 15% of the original participants having died, starting in 1986, 1997, and 2004. CONCLUSIONS: In older women, several commonly used dietary vitamin and mineral supplements may be associated with increased total mortality risk; this association is strongest with supplemental iron. In contrast to the findings of many studies, calcium is associated with decreased risk.

Rhinitis associated with pesticide use among private pesticide applicators in the agricultural health study.

Farmers commonly experience rhinitis but the risk factors are not well characterized. The aim of this study was to analyze cross-sectional data on rhinitis in the past year and pesticide use from 21,958 Iowa and North Carolina farmers in the Agricultural Health Study, enrolled 1993-1997, to evaluate pesticide predictors of rhinitis. Polytomous and logistic regression models were used to assess association between pesticide use and rhinitis while controlling for demographics and farm-related exposures. Sixty-seven percent of farmers reported current rhinitis and 39% reported 3 or more rhinitis episodes. The herbicides glyphosate [odds ratio (OR) = 1.09, 95% confidence interval (95% CI) = 1.05-1.13] and petroleum oil (OR = 1.12, 95% CI = 1.05-1.19) were associated with current rhinitis and increased rhinitis episodes. Of the insecticides, four organophosphates (chlorpyrifos, diazinon, dichlorvos, and malathion), carbaryl, and use of permethrin on animals were predictors of current rhinitis. Diazinon was significant in the overall polytomous model and was associated with an elevated OR of 13+ rhinitis episodes (13+ episodes OR = 1.23, 95% CI = 1.09-1.38). The fungicide captan was also a significant predictor of rhinitis. Use of petroleum oil, use of malathion, use of permethrin, and use of the herbicide metolachlor were significant in exposure-response polytomous models. Specific pesticides may contribute to rhinitis in farmers; agricultural activities did not explain these findings.

Antioxidant intake from fruits, vegetables and other sources and risk of non-Hodgkin's lymphoma: the Iowa Women's Health Study.

Antioxidant nutrients found in fruits, vegetables and other foods are thought to inhibit carcinogenesis and to influence immune status. We evaluated the association of these factors with risk of non-Hodgkin's lymphoma (NHL) overall and for diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma specifically in a prospective cohort of 35,159 Iowa women aged 55-69 years when enrolled at baseline in 1986. Diet was ascertained using a validated semiquantitative food frequency questionnaire. Through 2005, 415 cases of NHL (including 184 DLBCL and 90 follicular) were identified. Relative risks (RRs) and 95% confidence intervals (CIs) were estimated using Cox regression, adjusting for age and total energy. The strongest associations of antioxidants with risk of NHL (RR for highest versus lowest quartile; p for trend) were observed for dietary vitamin C (RR = 0.78; p = 0.044), alpha-carotene (RR = 0.71; p = 0.015), proanthocyanidins (RR = 0.70; p = 0.0024) and dietary manganese (RR = 0.62; p = 0.010). There were no associations with multivitamin use or supplemental intake of vitamins C, E, selenium, zinc, copper or manganese. From a food perspective, greater intake of total fruits and vegetables (RR = 0.69; p = 0.011), yellow/orange (RR = 0.72; p = 0.015) and cruciferous (RR = 0.82; p = 0.017) vegetables, broccoli (RR = 0.72; p = 0.018) and apple juice/cider (RR = 0.65; p = 0.026) were associated with lower NHL risk; there were no strong associations for other antioxidant-rich foods, including whole grains, chocolate, tea or nuts. Overall, these associations were mainly observed for follicular lymphoma and were weaker or not apparent for DLBCL. In conclusion, these results support a role for vegetables, and perhaps fruits and associated antioxidants from food sources, as protective factors against the development of NHL and follicular lymphoma in particular.

Cocoa and cardiovascular health.

Epidemiological data demonstrate that regular dietary intake of plant-derived foods and beverages reduces the risk of coronary heart disease and stroke. Among many ingredients, cocoa might be an important mediator. Indeed, recent research demonstrates a beneficial effect of cocoa on blood pressure, insulin resistance, and vascular and platelet function. Although still debated, a range of potential mechanisms through which cocoa might exert its benefits on cardiovascular health have been proposed, including activation of nitric oxide and antioxidant and antiinflammatory effects. This review summarizes the available data on the cardiovascular effects of cocoa, outlines potential mechanisms involved in the response to cocoa, and highlights the potential clinical implications associated with its consumption.

Mapping cancer for community engagement.

INTRODUCTION: Two research strategies may reduce health disparities: community participation and the use of geographic information systems. When combined with community participation, geographic information systems approaches, such as the creation of disease maps that connect disease rates with community context, can catalyze action to reduce health disparities. However, current approaches to disease mapping often focus on the display of disease rates for political or administrative units. This type of map does not provide enough information on the local rates of cancer to engage community participation in addressing disparities. METHODS: We collaborated with researchers and cancer prevention and control practitioners and used adaptive spatial filtering to create maps that show continuous surface representations of the proportion of all colorectal cancer cases diagnosed in the late stage. We also created maps that show the incidence of colorectal cancer. RESULTS: Our maps show distinct patterns of cancer and its relationship to community context. The maps are available to the public on the Internet and through the activities of Iowa Consortium for Comprehensive Cancer Control partners. CONCLUSION: Community-participatory approaches to research are becoming more common, as are the availability of geocoded data and the use of geographic information systems to map disease. If researchers and practitioners are to engage communities in exploring cancer rates, maps should be made that accurately represent and contextualize cancer in such a way as to be useful to people familiar with the characteristics of their local areas.

Coffee and caffeine intake and the risk of ovarian cancer: the Iowa Women's Health Study.

Laboratory data suggest that caffeine or some components of coffee may cause DNA mutations and inhibit tumor suppressor mechanisms, leading to neoplastic growth. However, coffee consumption has not been clearly implicated in the etiology of human postmenopausal ovarian cancer. This study evaluated the relationship of coffee and caffeine intake with risk of epithelial ovarian cancer in a prospective cohort study of 29,060 postmenopausal women. The participants completed a mailed questionnaire that assessed diet and health history and were followed for ovarian cancer incidence from 1986 to 2004. Age-adjusted and multivariate-adjusted hazard ratios were calculated for four exposure variables: caffeinated coffee, decaffeinated coffee, total coffee, and total caffeine to assess whether or not coffee or caffeine influences the risk of ovarian cancer. An increased risk was observed in the multivariate model for women who reported drinking five or more cups/day of caffeinated coffee compared to women who reported drinking none (HR = 1.81, 95% CI: 1.10-2.95). Decaffeinated coffee, total coffee, and caffeine were not statistically significantly associated with ovarian cancer incidence. Our results suggest that a component of coffee other than caffeine, or in combination with caffeine, may be associated with increased risk of ovarian cancer in postmenopausal women who drink five or more cups of coffee a day.

Constipation in pregnancy: prevalence, symptoms, and risk factors.

OBJECTIVE: To prospectively estimate constipation prevalence and risk factors in pregnancy. METHODS: We enrolled healthy pregnant women in this longitudinal study during the first trimester. At each trimester and 3 months postpartum, participants completed a self-administered bowel symptom questionnaire, physical activity and dietary fiber intake measures, and a prospective 7-day stool diary. Constipation was defined using the Rome II criteria (presence of at least two of the following symptoms for at least one quarter of defecations: straining, lumpy or hard stools, sensation of incomplete evacuation, sensation of anorectal obstruction, manual maneuvers to facilitate defecation, and fewer than three defecations per week). Generalized linear logistic models explored factors associated with constipation during pregnancy. RESULTS: One hundred three women were enrolled with mean (+/-standard deviation) age of 28 (+/-5) years; 54% were nulliparous and 92% white. Constipation prevalence rates were 24% (95% confidence interval [CI] 16-33%), 26% (95% CI 17-38%), 16% (95% CI 8-26%), and 24% (95% CI 13-36%) in the first, second, and third trimesters and 3 months postpartum, respectively. Additionally, irritable bowel syndrome (by Rome II criteria) prevalence rates were 19% (95% CI 12-28%), 13% (95% CI 6-23%), 13% (95% CI 6-23%) and 5% (95% CI 1-13%) in the first, second, and third trimesters and 3 months postpartum, respectively. In multivariable longitudinal analysis, iron supplements (OR 3.5, 95% CI 1.04-12.10) and past constipation treatment (OR 3.58, 95% CI 1.50-8.57) were associated with constipation during pregnancy. CONCLUSION: Constipation measured using the Rome II criteria affects up to one fourth of women throughout pregnancy and at 3 months postpartum. LEVEL OF EVIDENCE: II.

Vitamin D intake and breast cancer risk in postmenopausal women: the Iowa Women's Health Study.

Vitamin D, a prosteroid hormone with anti-proliferative and pro-differentiation activity, is thought to act as a cancer chemopreventive agent. This study evaluated the association between vitamin D intake and breast cancer risk among women in a large prospective cohort study. A total of 34,321 postmenopausal women who had completed a questionnaire that included diet and supplement use were followed for breast cancer incidence from 1986 to 2004. Adjusted relative risks (RR) for breast cancer were calculated for dietary, supplemental, and total vitamin D intake among all women. The adjusted RR of breast cancer for women consuming >800 IU/day versus <400 IU/day total vitamin D was 0.89 (95% CI: 0.77-1.03). RRs were stronger among women with negative than positive ER or PR status. The association of high vitamin D intake with breast cancer was strongest in the first 5 years after baseline dietary assessment (RR = 0.66; 95% CI: 0.46-0.94 compared with lowest-intake group), and diminished over time. Changes in vitamin D intake over time might have contributed to the diminished association observed in later years. Vitamin D intake of >800 IU/day appears to be associated with a small decrease in risk of breast cancer among postmenopausal women. Studies evaluating all sources of vitamin D, especially sun exposure, are needed to fully understand the association between vitamin D and breast cancer risk.

Vitamin D deficiency in breastfed infants in Iowa.

OBJECTIVE: The purpose of this work was to assess the vitamin D status of breastfed infants living in Iowa (latitude: 41 degrees N). METHODS: Blood samples and dietary records from 84 breastfed infants participating in another study were used for a survey of vitamin D status at 280 days of age. The vitamin D status of those (35 infants) who did not receive preformed vitamin D at 280 days of age (unsupplemented infants) was assessed longitudinally between 112 days and 15 months of age. Plasma 25-hydroxyvitamin D and, in most cases, parathyroid hormone and alkaline phosphatase were determined. RESULTS: At 280 days of age, 10% of breastfed infants were vitamin D deficient (25-hydroxyvitamin D < 11 ng/mL). Deficiency was significantly more prevalent among dark-skinned infants and during winter and occurred exclusively in unsupplemented infants. During winter, 78% of unsupplemented infants were vitamin D deficient. During summer, only 1 infant who had dark skin pigmentation was vitamin D deficient. Longitudinal assessment of unsupplemented infants similarly showed that the majority of breastfed infants were vitamin D deficient during winter. Severe deficiency (25-hydroxyvitamin D < 5 ng/mL) was common and was accompanied by elevation of parathyroid hormone and alkaline phosphatase. The prevalence of vitamin D deficiency decreased with age but was still 12% at 15 months of age if no preformed vitamin D was received. CONCLUSIONS: Vitamin D deficiency, including severe deficiency, was common among breastfed infants in Iowa who did not receive preformed vitamin D. Deficiency occurred mostly during winter but was not completely absent during summer. It affected infants with light as well as dark skin pigmentation. Consumption of preformed vitamin D from vitamin supplements or formula is effective in preventing vitamin D deficiency. Vitamin D supplementation should be provided to all breastfed infants.

Coffee consumption and risk of type 2 diabetes mellitus: an 11-year prospective study of 28 812 postmenopausal women.

BACKGROUND: Coffee intake may be associated with reduced risk of type 2 diabetes mellitus because of minerals, phytochemicals, and antioxidants in coffee, but the role of caffeine is unclear. Our objective was to examine the association between total, caffeinated, and decaffeinated coffee intake, as assessed by food frequency questionnaire at baseline, and risk of incident type 2 diabetes mellitus. METHODS: This prospective analysis of the Iowa Women's Health Study (1986-1997) included 28 812 postmenopausal women free of diabetes and cardiovascular disease in the general community. The main outcome measure was incident type 2 diabetes mellitus as determined by mailed questionnaire. RESULTS: Coffee intake was categorized as 0, less than 1, 1 to 3, 4 to 5, and 6 or more cups per day. During 11 years of follow-up, there were 1418 incident cases of diabetes. Relative risks (RRs) were adjusted for a variety of demographic, adiposity, and lifestyle measures. Compared with women who reported 0 cups of coffee per day, women who consumed 6 or more cups per day had a 22% lower risk (RR = 0.78; 95% confidence interval [CI], 0.61-1.01) of diabetes (P for linear trend across categories, .06). This association appeared to be largely explained by decaffeinated coffee (RR = 0.67; 95% CI, 0.42-1.08; P for trend, .006) rather than regular coffee (RR = 0.79; 95% CI, 0.59-1.05; P for trend, .90). Intake of magnesium and phytate did not explain these associations. Intakes of caffeine from all sources was not associated with risk of diabetes. CONCLUSION: Coffee intake, especially decaffeinated, was inversely associated with risk of type 2 diabetes mellitus in this cohort of postmenopausal women.

Interaction among heme iron, zinc, and supplemental vitamin C intake on the risk of lung cancer: Iowa Women's Health Study.

Redox-active iron present at physiological levels in the pulmonary epithelial lining fluid may lead to damage of lung tissue under some circumstances. For example, factors that increase potential for oxidative stress, such as higher intake of heme iron or higher intake of vitamin C in the presence of high intake of iron, might increase the risk of lung cancer, whereas higher intake of the antioxidant zinc might decrease that risk. During 16 yr of follow-up, 34,708 postmenopausal women, aged 55-69 yr at baseline who completed a food-frequency questionnaire for the Iowa Women's Health Study, were followed for 700 incident lung cancers. When subjects were stratified by intake of vitamin C supplements, among women who took vitamin C supplements of >500 mg/day, after adjusting for age, total energy intake, cigarette smoking, alcohol consumption, and dietary zinc or dietary heme iron intake, relative risks across categories of dietary heme iron intake were 1.0, 0.85, 0.93, 1.32, 1.70, and 3.77 (P for trend = 0.05; P for interaction = 0.08), whereas corresponding figures for dietary zinc intake were 1.0, 1.15, 0.71, 0.84, 0.61, and 0.11 (P for trend = 0.12; P for interaction = 0.04). The strength of the associations of heme iron and zinc intake with lung cancer appeared to be stronger with increasing levels of vitamin C supplement intake. Our results suggest that high dietary heme iron intake may increase the risk of lung cancer, whereas high dietary zinc may decrease the risk of lung cancer among postmenopausal women who consume high-dose vitamin C supplements. This finding may be of particular importance to smokers, for whom vitamin C supplementation is a common recommendation.