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Objective: To examine the association between walnut consumption and measures of cognitive function in the US population. Design: Nationally representative cross sectional study using 24 hour dietary recalls of intakes to assess walnut and other nut consumption as compared to the group reporting no nut consumption. Setting: 1988-1994 and 1999-2002 rounds of the National Health and Nutrition Examination Survey (NHANES). Population: Representative weighted sample of US adults 20 to 90 years of age. Main Outcome Measure: The Neurobehavioral Evaluation System 2 (NES2), consisting of simple reaction time (SRTT), symbol digit substitution (SDST), the single digit learning (SDLT), Story Recall (SRT) and digit-symbol substitution (DSST) tests. Results: Adults 20-59 years old reporting walnut consumption of an average of 10.3 g/d required 16.4ms less time to respond on the SRTT, P=0.03, and 0.39s less for the SDST, P=0.01. SDLT scores were also significantly lower by 2.38s (P=0.05). Similar results were obtained when tertiles of walnut consumption were examined in trend analyses. Significantly better outcomes were noted in all cognitive test scores among those with higher walnut consumption (P < 0.01). Among adults 60 years and older, walnut consumers averaged 13.1 g/d, scored 7.1 percentile points higher, P=0.03 on the SRT and 7.3 percentile points higher on the DSST, P=0.05. Here also trend analyses indicate significant improvements in all cognitive test scores (P < 0.01) except for SRTT (P = 0.06) in the fully adjusted models. Conclusion: These significant, positive associations between walnut consumption and cognitive functions among all adults, regardless of age, gender or ethnicity suggest that daily walnut intake may be a simple beneficial dietary behavior. [ABSTRACT FROM AUTHOR]

Objective: To examine the utility of using external estimates of within-person variation to adjust usual nutrient intake distributions.Design: Analyses of the prevalence of inadequate intake of an example nutrient by the Estimated Average Requirement (EAR) cut-point method using three different methods of statistical adjustment of the usual intake distribution of a single 24-hour recall in Russian children in 1996, using the Iowa State University method for adjustment of the distribution. First, adjusting the usual intake distribution with day 2 recalls from the same 1996 sample (the correct method); second, adjusting the distribution using external variance estimates derived from US children in 1996; and third, adjusting the distribution using external estimates derived from Russian children of the same age in 2000. We also present prevalence estimates based on nave statistical analysis of the unadjusted distribution of intakes.Setting/subjects: Children drawn from the Russia Longitudinal Monitoring Survey in 1996 and 2000 and from the 1996 Continuing Survey of Food Intakes by Individuals.Results: When the EAR cut-point method is applied to a single recall, the resulting prevalence estimate in this study is inflated by 1001300%. When the intake distribution is adjusted using an external variance estimate, the prevalence estimate is much less biased, suggesting that any adjustment may give less biased estimates than no adjustment.Conclusions: In moderately large samples, adjusting distributions with external estimates of variances results in more reliable prevalence estimates than using 1-day data. [ABSTRACT FROM AUTHOR]

Abstract: The epidemiologic findings on the relationship between alcohol consumption and colon cancer are inconsistent. The National Health and Nutrition Examination Survey (NHANES) I Epidemiologic Follow-Up Study (NHEFS) included a prospective cohort population representative of the general U.S. population, which had not been fully utilized for examining the risk between colon cancer and alcohol drinking. The NHEFS consisted of 10,220 participants prospectively followed over a decade. Alcohol consumption, amount and type of beverage, and drinking patterns at baseline were considered in examination of the effect of alcohol consumption on the risk of colon cancer. The consumption of one or more alcoholic beverages a day at baseline was associated with approximately a 70% greater risk of colon cancer [relative risk (RR) = 1.69; 95% confidence interval (CI) = 1.03, 2.79], with a strong positive dose-response relationship (P = 0.04). This association appeared to be exclusively related to daily drinking of one or more drinks of liquor (RR = 2.48; 95% CI = 1.66, 4.53). Additionally, more than a 70% increased risk of colon cancer was observed for more than 34 yr of alcohol drinking history compared with nondrinkers (RR = 1.73; 95% CI = 1.08, 2.78). Overall, alcohol consumption was significantly associated with increased risk of colon cancer. The most important factor for colon cancer seems to be liquor consumption. [ABSTRACT FROM AUTHOR]

Within- and between-person variation in nutrient intake has been characterized in different adult populations, but little is known of country, age, or sex differences among children. The objectives of this study were as follows: 1) to describe the mean intake, within- and between-individual CV and variance ratios of nutrient intake among children ages 9-18 y old in Russia and the United States in 1996; 2) to compare the age and sex-related differences in nutrient intake variance within and between countries; and 3) to hypothesize about the feasibility of using within-individual variance estimates from one nationally representative sample to adjust the usual intake distributions in another nationally representative sample. Mean intakes of all nutrients except magnesium were significantly higher among U.S. children (P < 0.001); within-person variation was higher among the U.S. children, possibly indicating greater access to a wide array of foods. Strong differentials existed in variance components by sex in both countries, although not in the same direction, and differed by age in U.S. girls. Ratios of within- to between-person variance in 8 of 11 nutrients were lower among Russian (range: 0.9-1.6) than U.S. children (range: 1.4-1.7), suggesting that day-to-day bias may not affect Russian dietary recalls as strongly as in the United States. Researchers are encouraged to use these estimates to conduct sensitivity analyses of usual intake distributions in their own data when multiple days of data collection are not feasible. [ABSTRACT FROM AUTHOR]