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41.
BackgroundDietary supplement use is common, particularly among cancer survivors and those at increased risk for cancer.ObjectiveThe objectives of this study were to assess 1-year test–retest reproducibility of dietary supplement use reported via food frequency questionnaire (FFQ-1 vs FFQ-2) and relative validity in comparison to repeated 24-hour dietary recalls (FFQ-2 vs DRs).DesignThis ancillary study was conducted within a large prospective cohort, the American Cancer Society’s Cancer Prevention Study-3.Participants/settingBetween 2015 and 2016, 684 participants in the United States (64% women; 62% non-Hispanic White, 23% non-Hispanic Black, and 15% Hispanic) completed two FFQs and up to six unannounced telephone interviewer-administered DRs over 1 year as part of the Cancer Prevention Study-3 Diet Assessment Substudy.Primary outcome measuresFFQs queried current multivitamin-mineral supplement (≥10 components) use, frequency and dose (range) for seven supplements taken individually or as part of a complex (individual/complex) including calcium, vitamins D, C, and E, folic acid, fish oil, and glucosamine. DRs allowed exact reporting of supplement frequency and dose.Statistical analysesWeighted κ statistics were used to evaluate reproducibility between FFQ-1 and FFQ-2 and Spearman correlation coefficients assessed agreement between supplemental nutrient amounts assessed by FFQ-2 and the average of DRs.ResultsJust more than half of the participants reported taking multivitamin-mineral supplements on the baseline FFQ. Kappa statistics for the comparison of categorical responses between FFQ-1 and FFQ-2 were 0.67 for multivitamin-mineral supplements. Kappas for individual/complex supplements ranged from 0.47 for folic acid to 0.74 for vitamin D, with a mean of 0.64. Results were similar between men and women. Spearman correlation coefficients comparing FFQ-2 with the average of DRs (validity) for nutrient intakes from all sources ranged from 0.65 (fish oil for women) to 0.77 (vitamin D for men and calcium for women); results were similar among men and women.ConclusionsThese findings suggest the FFQ used in Cancer Prevention Study-3 has good reproducibility over 1 year and yields estimates comparable to a more detailed assessment for commonly consumed dietary supplements.  相似文献   
42.
BackgroundCurrent dietary guidelines recommend avoiding foods and beverages with added sugars and higher sodium before age 2 years.ObjectiveThe aim was to describe daily snack food intake (frequency and total energy) and the associations with overconsumed nutrients (added sugars, sodium, and saturated fats) and child weight-for-length z scores.DesignA cross-sectional, secondary analysis of baseline data from an ongoing longitudinal intervention was conducted.Participants and settingA sample of 141 caregivers with infants (aged 9 to 11 months) and toddlers (aged 12 to 15 months) was recruited in Buffalo, NY, between 2017 and 2019.Main outcome measuresThree 24-hour dietary recalls were used to categorize 'sweet and salty snack foods' or 'commercial baby snack foods' based on the US Department of Agriculture What We Eat in America food group classifications and estimate nutrient intakes. Child recumbent length and weight were measured by trained researchers.Statistical analysisDaily frequency (times/day), energy (kcal/day), and overconsumed nutrients from snack food intake were calculated. Multivariable regression models examined associations between the frequency of and energy from snack food intake with overconsumed nutrients and child weight-for-length z scores.ResultsInfants consumed snack foods on average 1.2 times/day contributing 5.6% of total daily energy, 19.6% of added sugars, and 6.8% of sodium. Toddlers consumed snack foods on average 1.4 times/day contributing 8.9% of total daily energy, 40.0% of added sugars, and 7.2% of sodium. In adjusted models including all children, greater frequency of sweet and salty snack food intake, but not commercial baby snack foods, was associated with higher weight-for-length z scores.ConclusionsSnack foods are frequently consumed by infants and toddlers and contribute to the intake of overconsumed nutrients such as added sugars and sodium. Given the current guidelines to avoid added sugars and higher sodium before age 2 years, additional recommendations related to nutrient-dense snack intake may be beneficial.  相似文献   
43.
BackgroundCalcium, one of the most abundant minerals in the human body, has a pivotal role in human physiology. However, only a few studies have examined the association of dietary calcium intake with mortality in a population with low calcium intake.ObjectiveThe aim of this study was to examine the association of dietary calcium intake with risk of all-cause and cause-specific mortality among Korean adults with low calcium intake.DesignThis study was a prospective cohort study.Participants/settingThe analysis was conducted using data from 44,327 eligible Korean adults aged 19 years and older who participated in the Korea National Health and Nutrition Examination Survey 2007-2015. Dietary calcium intake was assessed using 1-day 24-hour recall data.Main outcome measuresThe main outcomes of this study were mortality from all causes, cancer, cardiovascular disease, respiratory disease, and all other causes combined. The outcome was ascertained through linkage to the death registry compiled by Statistics Korea with the use of the resident registration number.Statistical analyses performedWeighted Cox proportional hazard models were used to estimate the hazard ratios and 95% CIs of the all-cause and cause-specific mortality according to dietary calcium intake.ResultsDuring a mean follow-up of 7.28 person-years, 1,889 deaths were ascertained. After multivariable adjustment, the hazard ratios for all-cause mortality for the second quintile to the highest quintile of dietary calcium intake, respectively, compared with the first quintile were 0.86 (95% CI 0.73 to 1.00), 0.82 (95% CI 0.69 to 0.98), 0.85 (95% CI 0.69 to 1.03), and 0.78 (95% CI 0.64 to 0.96) (P for trend from the lowest to the highest quintile = .04). There were no statistically significant associations between dietary calcium intake and risk of mortality from cancer, cardiovascular, or respiratory disease.ConclusionsIn this large prospective cohort study of Korean adults, lower dietary calcium intake was associated with a higher risk of all-cause mortality.  相似文献   
44.
BackgroundAlcohol and tobacco are the major risk factors for oral and pharyngeal cancer, but diet is likely to have a role, too.ObjectiveThe objective was to analyze the relationship between adherence to the 2015-2020 Dietary Guidelines for Americans (DGA), as measured by the Healthy Eating Index 2015 (HEI-2015), and oral and pharyngeal cancer risk. Moreover, this work aimed to quantify the number of avoidable cases under different scenarios of increased adherence to the DGA, with the use of the potential impact fraction. This estimates the proportion of cases that would occur if the distribution of the risk factor in the population followed an alternative distribution.DesignA multicenter, case–control study was conducted in Italy between 1991 and 2009. Participants’ usual diet for the 2 years preceding study enrolment was assessed using a food frequency questionnaire.Participants and settingCases were 946 patients admitted to major hospitals with incident, histologically confirmed oral and pharyngeal cancer. Controls were 2,492 patients admitted to the same hospitals for acute non neoplastic conditions.Main outcome measuresThe adherence to the DGA was assessed using the HEI-2015 score (range = 0 to 100), based on 13 components. The outcome was oral and pharyngeal cancer.Statistical analyses performedOdds ratios and the corresponding 95% CIs were estimated using multiple logistic regression models adjusted for tobacco, alcohol, and other relevant covariates. The potential impact fraction was estimated under different scenarios of adherence to the DGA.ResultsIn this Italian population the HEI-2015 score ranged from 33.4 to 97.5. A higher HEI-2015 score was associated with a lower risk of oral and pharyngeal cancer, with an odds ratio of 0.70 (95% CI 0.62 to 0.79) for a 10-point increment of the score. The estimated potential impact fraction was 64.8% under the maximum achievable reduction scenario, and it ranged from 9% to 27% following other more feasible scenarios.ConclusionsThe HEI-2015 score was inversely related to oral and pharyngeal cancer risk in this Italian population. This analysis allowed for the estimation of the fraction of preventable cases, under different feasible scenarios. A share of 9% to 27% of avoidable cases of oral and pharyngeal cancer might be obtained across real-world scenarios of adherence to the DGA as measured by the HEI-2015 score.  相似文献   
45.
BackgroundUnderstanding how vegetables are incorporated into the diet, especially in the types and amounts recommended by the Dietary Guidelines for Americans, and how this alters dietary intake patterns is vital for developing targeted behavior change interventions.ObjectiveTo determine how a provision of vegetables was incorporated into the diet of adults with overweight and obesity; whether or not the provided vegetables displaced other foods; and what, if any, effect this had on diet quality and body weight and composition.DesignThis study investigated secondary outcomes from the Motivating Value of Vegetables Study, a community-based, randomized, parallel, nonblinded controlled trial. Participants were randomly assigned to a provided vegetable intervention or attention control group using a one to one allocation ratio.Participants/settingMen and women with self-reported low vegetable consumption, aged 18 to 65 years, with a body mass index ≥25 were recruited from Grand Forks, ND, between October 2015 and September 2017. Only participants randomized to the provided vegetable intervention group (n = 51; attrition = 8%) were included in this secondary analysis.InterventionDietary Guidelines for Americans recommended types and amounts of vegetables were provided weekly for 8 weeks.Main outcome measuresHow the provided vegetables were incorporated into the diet was measured using daily self-report and 24-hour dietary recalls. Diet quality was assessed via the Healthy Eating Index 2015. Body weight and composition were measured before and after the intervention.Statistical analyses performedData were assessed using generalized linear mixed models where phase (pre, post) was the within-subject factor and subject was the random effect.ResultsParticipants self-reported using 29% of the provided vegetables as substitutes for other foods. With the increase in vegetable consumption, there were decreases in total grains (mean difference ± standard deviation; –0.97 ± 3.23 oz-equivalents; P = 0.02), protein foods (–1.24 ± 3.86 oz-equivalents; P = 0.01), saturated fats (–6.44 ± 19.63 g; P = 0.02), and added sugars (–2.44 ± 6.78 tsp-equivalents; P = 0.02) consumed. Total Healthy Eating Index 2015 scores increased (+4.48 ± 9.63; P = 0.001) and dietary energy density decreased (–0.44 ± 0.52 kcal/g; P < 0.0001). There was no change in total energy intake or body weight and composition.ConclusionsIncreasing vegetable consumption to meet Dietary Guidelines for Americans recommendations alters dietary intake patterns, improving diet quality and energy density. These findings highlight the importance of characterizing how individuals incorporate Dietary Guidelines for Americans recommendations into their diet.  相似文献   
46.
BackgroundPuerto Rican adults residing in the US mainland experience a high prevalence of metabolic syndrome (MetS). A diet containing healthy protein-rich sources may help control risk factors for MetS.ObjectiveThis study aimed to evaluate 2-year longitudinal associations between intake of various protein-rich foods and changes in the six MetS components.DesignThis is a secondary analysis of a longitudinal cohort study using data from the baseline (2004–2007) and 2-year follow-up visits (2006–2011) in the Boston Puerto Rican Health Study.Participants/settingParticipants were self-identified Puerto Ricans, aged 45 to 75 years, residing in Boston, Massachusetts, or the surrounding area (n = 1,126).Main outcome measuresMetS components were fasting glucose, high-density lipoprotein (HDL) cholesterol, triglycerides, systolic and diastolic blood pressures, and waist circumference.Statistical analysisBaseline intake of foods reported in a semiquantitative food frequency questionnaire were expressed as servings/day, and protein-rich foods were categorized as unprocessed white meat, unprocessed red meat, processed meat, milk and yogurt, cheese, fish and seafood, beans, nuts, and eggs. Associations between each continuous protein food group and continuous 2-year change in MetS components were assessed using linear mixed models adjusted for socioeconomic and behavioral factors, and other dietary sources.ResultsThe top contributors to total protein intake were unprocessed red meat (13.3%) and unprocessed poultry (13.0%), and the lowest were eggs (2.92%) and nuts (0.91%). Higher intake of processed meats was associated with an increase in waist circumference over 2 years (β = 1.28; standard error [SE] = 0.63), whereas higher intake of fish and seafood was associated with a decrease in waist circumference (β = ?3.47; SE = 1.39). Intake of unprocessed poultry was associated with a decrease in triglycerides (β = ?24.5; SE = 9.13). No other significant associations were observed between protein sources and 2-year changes in MetS components.ConclusionsConsuming less processed meat and more fish and seafood and unprocessed poultry was associated with decreases in waist circumference and triglycerides among US mainland Puerto Ricans. Other dietary protein sources were not related to cardiometabolic health.  相似文献   
47.
48.
目的 对膳食炎症指数(DII)与慢性肾脏病发病之间的研究进行综述,探究两者之间的关系。方法 以“膳食炎症指数”、“促炎饮食”和“慢性肾脏病”、“肾小球滤过率”为检索词,在PubMed, Web of Science和EMBASE等数据库进行检索,查询并严格筛选合格文献,进一步综述膳食炎症指数与慢性肾病的流行病学关系,并从炎症因子方面解释阐述了膳食炎症指数与慢性肾病之间可能的相关机制。结果 促炎饮食会造成慢性肾脏病的发病风险升高,相反,抗炎饮食可以有效降低慢性肾脏病的发病风险,特定的炎症因子标志物对慢性肾脏病的发病有特定作用。结论 膳食炎症指数对慢性肾脏病的发生有一定的影响,未来可能作为慢性肾病发病的预防控制策略之一,并可能给肾脏疾病的防治提供重要的科学依据。  相似文献   
49.
Gastric cancer etiology: a biochemical hypothesis.   总被引:1,自引:0,他引:1  
We have proposed a two-stage biochemical model for the etiology of "intestinal" gastric cancer. The model postulates that the gastric mucosal barrier is biochemically pierced as a result of chemical interactions between the mucoproteins and mucopolysaccharides of the barrier and ingested polysaccharrides (starches). This would allow the growth of gastric flora which could produce carcinogenic nitrosamines and/or nitrosamides. Observational and experimental evidence in favor of the model is provided. The model suggests various research initiatives, the results of which might provide the basis for biochemical and physiological methods for the prevention and/or treatment of gastric cancer. Various ways in which the model may be tested are also noted.  相似文献   
50.
This randomised double-blind study examined the frequency of diarrhoea in intensive care unit patients given a fibre-containing feed, Enrich, and a fibre-free feed, Ensure. A daily diarrhoea score was calculated from the frequency, volume and consistency of the stools. A score greater than 12 indicated diarrhoea, and greater than 50 severe diarrhoea. Ninety one patients met the criteria for participation: Enrich 45, Ensure 46. The groups were similar in age, sex ratio, feed volume, antibiotic usage, upper gastro-intestinal bleeding prophylaxis and plasma albumin concentrations. Diarrhoea occurred in 16 patients given Enrich and 13 given Ensure, severe diarrhoea affecting 5 and 9 respectively (NS). Forty seven of 343 (14%) Enrich feeding days and 51 of 342 (15%) Ensure feeding days were complicated by diarrhoea — severe diarrhoea: 8 and 12 feeding days (NS). We conclude soy polysaccharide (21 g/L) did not reduce diarrhoea in intensive care unit patients given enteral feeds.  相似文献   
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