Dietary N-Nitroso Compounds and Risk of Hepatocellular Carcinoma: A USA-Based Study

BACKGROUND AND AIMS

N-nitroso compounds (NOCs) are among the most potent dietary carcinogens. N-nitrosodiethylamine (NDEA), N-nitrosodimethylamine (NDMA), and N-nitrosopiperidine (NPIP) are abundant in foods and carcinogenic to the liver. We investigated the relationship between dietary NOCs and HCC risk.

APPROACH AND RESULTS

In this large, hospital-based, case-control study of 827 pathologically or radiologically confirmed HCC cases and 1,013 controls, NOC intake was calculated by linking food frequency questionnaire-derived dietary data with a comprehensive NOC concentration database. Multivariable-adjusted ORs and 95% CIs of HCC by quartiles of NOC consumption were estimated using logistic regression models, with the lowest quartile as the referent. We further investigated joint effects of consuming the highest quartile of NOCs that were associated with increased HCC risk and hepatitis, diabetes, or alcohol drinking on HCC risk. After adjustment for confounding factors, higher intake of NDEA from plant sources (ORQ4 vs. Q1  = 1.58; 95% CI = 1.03-2.41), NDMA from plant sources (ORQ4 vs. Q1  = 1.54; 95% CI = 1.01-2.34), and NPIP (ORQ4 vs. Q1  = 2.52; 95% CI = 1.62-3.94) was associated with increased HCC risk. No association was observed for nitrate or total NOC intake and HCC risk. Higher consumption of HCC-inducing NOCs and positive hepatitis virus status jointly increased the risk of developing HCC.

CONCLUSIONS

In conclusion, though some of our findings may indicate the presence of reverse causation owing to lower meat intake among cases with chronic liver diseases before HCC diagnosis, the potent dietary HCC carcinogens, NDEA, NDMA, and NPIP, and their enhanced carcinogenic effects among chronic carriers of hepatitis virus warrant further prospective investigation.

Dietary N-nitroso compounds and risk of pancreatic cancer: results from a large case-control study

N-nitroso compounds (NOCs) are among the most potent dietary and pancreatic carcinogens. N-nitrosodiethylamine (NDEA) and N-nitrosodimethylamine (NDMA) are the most prevalent NOCs identified in foods. Using a validated and comprehensive N-nitroso database developed to estimate total NOCs and important individual NOCs from food intake, we investigated dietary exposure to NOCs in relation to pancreatic cancer in a large matched case-control study. Self-administered food frequency questionnaires were collected from 957 pathologically confirmed pancreatic ductal adenocarcinoma cases and 938 frequency-matched controls. For each food item, frequency of intake and portion size in grams was multiplied by the estimated NOC concentration from the N-nitroso database. Multiple unconditional logistic regression models were used to estimate the odds ratios (OR) and 95% confidence intervals (CIs) for pancreatic cancer risk by quartiles of NOCs and major food group contributors to NOCs, with the lowest quartile as referent. Following adjustment for confounders, we observed significant positive associations for NDEA (ORQ4 versus Q1 = 2.28, 95% CI = 1.71-3.04, Ptrend < 0.0001) and NDMA from plant sources (ORQ4 versus Q1 = 1.93, 95% CI = 1.42-2.61, Ptrend < 0.0001) with pancreatic cancer. The major food groups related to NDEA and NDMA intakes in this population were fermented cheese, pizza, grains, seafood and beer. No associations of intake of nitrate or total NOCs were observed; nitrite was inversely associated with pancreatic cancer. Although some of our findings probably reflect reverse causation bias due to lower meat intake in cases with latent disease, biologically plausible findings for pancreatic carcinogens, NDEA and NDMA, warrant further prospective investigation.

Breakfast consumption has no effect on neuropsychological functioning in children: a repeated-measures clinical trial

BACKGROUND

Although many studies have investigated the relation between breakfast consumption and various domains of cognitive functioning within children, some of the reported findings are inconsistent.

OBJECTIVE

We sought to determine the short-term effects of a breakfast meal on the neuropsychological functioning of healthy school-aged children after an overnight fast.

DESIGN

The study was conducted in a clinical research center with the use of a counterbalanced repeated-measures design among children who either consumed breakfast or were fasting. The administered neuropsychological tests included measures of attention, impulsivity, short-term memory, cognitive processing speed, and verbal learning. The sample consisted of children aged 8-10 y (n = 128), of whom 52% were female, 38% were African American, 31% were Hispanic, 28% were white, and 3% were of another race/ethnicity.

RESULTS

There were no significant (P ≥ 0.004) differences between breakfast meal consumption and fasting for any of the neuropsychological measures administered.

CONCLUSION

Breakfast consumption had no short-term effect on neuropsychological functioning in healthy school-aged children. This trial was registered at clinicaltrials.gov as NCT01943604.

Validity and feasibility of a digital diet estimation method for use with preschool children: a pilot study

OBJECTIVE

The goal of the study was to assess the validity and feasibility of a digital diet estimation method for use with preschool children in Head Start.

METHODS

Preschool children and their caregivers participated in validation (n = 22) and feasibility (n=24) pilot studies. Validity was determined in the metabolic research unit using actual gram weight measurements as the reference method. Feasibility of using the digital diet estimation method was determined in Head Start and in the home by assessing 3 separate lunch and dinner meals.

RESULTS

The average correlation between estimated weights and actual weights was 0.96 (P < .001), and the average mean difference was 10.6 g. The digital diet estimates were 5% lower than the actual weights.

CONCLUSIONS AND IMPLICATIONS

The digital diet estimation method may be a valid and feasible method for assessing food intake of preschool children.

General versus central adiposity and relationship to pediatric metabolic risk

BACKGROUND

The influence of moderate-to-vigorous physical activity (MVPA) and general versus central adiposity on pediatric metabolic risk is not well described.

METHODS

Secondary analyses on pediatric participants from the National Health and Nutrition Examination Survey, 2003-2006 (n=2,155). MVPA (min/day) and adherence to MVPA recommendations were assessed objectively by accelerometers. Body mass index (BMI) z-score and waist circumference (WC) were measured by standard protocols. The main dependent variables included an overall metabolic risk score and clinical tests related to metabolic risk. A series of linear regression analyses were used to examine BMI z-score versus WC as a mediator of the relationship between MVPA and the metabolic risk score or the individual components, controlling for sociodemographic covariates. All analyses with BMI z-score as an independent variable controlled for WC and vice versa. The product-of-coefficients method was used to test for mediation.

RESULTS

MVPA adherence was inversely associated and WC was positively associated with the metabolic risk score (all P<0.05). MVPA was inversely associated with systolic blood pressure and positively associated with high-density lipoprotein cholesterol (HDL-C) (all P<0.05). WC was inversely associated with HDL-C and positively associated with C-reactive protein (CRP), glycohemoglobin, fasting triglycerides, and fasting insulin (all P<0.05). WC mediated the relationship between MVPA and CRP or HDL-C (both P<0.05).

CONCLUSIONS

MVPA correlated with pediatric metabolic risk and this relationship was mediated by central adiposity for CRP and HDL-C. This finding suggests the need for programs to screen for and improve children's MVPA and WC.

Perceptions of community nutrition and health needs in the Lower Mississippi Delta: a key informant approach

OBJECTIVE

Key informants' perceptions of nutrition and health needs in their southern rural communities were assessed prior to nutrition intervention planning.

DESIGN

This cross-sectional survey used in-person interviews.

SUBJECTS/SETTINGS

A sample of 490 individuals from 12 professional and lay roles in 8 community sectors in 36 counties in Arkansas, Louisiana, and Mississippi was chosen.

STATISTICAL ANALYSES PERFORMED

Factor analysis was carried out on reported food, nutrition, and health problems and contributing factors. The General Linear Models procedure identified within- and between-subject effects for factors. Tukey's post hoc tests identified differences between sectors and states. Frequencies and weighted rankings were computed for health problems.

RESULTS

Key informants rated individual-level factors (food choices, education, willingness to change, health behavior) as more important than community-level factors (food and health care access, resources) with regard to nutrition and health problems and contributors to problems. The number one health problem was hypertension.

IMPLICATIONS

Key informants are knowledgeable about nutrition and health problems, contributing factors, and available resources. Individual factors were perceived as more important contributors to nutrition and health problems providing valuable information for planning nutrition interventions.

Validity of a telephone-administered 24-hour dietary recall in telephone and non-telephone households in the rural Lower Mississippi Delta region

OBJECTIVE

To determine if 24-hour dietary recall data are influenced by whether data are collected by telephone or face-to-face interviews in telephone and non-telephone households.

DESIGN

Dual sampling frame of telephone and non-telephone households. In telephone households, participants completed a 24-hour dietary recall either by face-to-face interview or telephone interview. In non-telephone households, participants completed a 24-hour dietary recall either by face-to-face interview or by using a cellular telephone provided by a field interviewer.

SUBJECTS/SETTING

Four hundred nine participants from the rural Delta region of Arkansas, Louisiana, and Mississippi.

MAIN OUTCOME MEASURES

Mean energy and protein intakes.

STATISTICAL ANALYSES PERFORMED

Comparison of telephone and non-telephone households, controlling for type of interview, and comparison of telephone and face-to-face interviews in each household type using unpaired t tests and linear regression, adjusting for gender, age, and body mass index.

RESULTS

Mean differences between telephone and face-to-face interviews for telephone households were -171 kcal (P = 0.1) and -6.9 g protein (P = 0.2), and for non-telephone households -143 kcal (P = 0.6) and 0.4 g protein (P = 1.0). Mean differences between telephone and non-telephone households for telephone interviews were 0 kcal (P = 1.0) and -0.9 g protein (P = 0.9), and for face-to-face interviews 28 kcal (P = 0.9) and 6.4 g protein (P = 0.5). Findings persisted when adjusted for gender, age, and body mass index. No statistically significant differences were detected for mean energy or protein intake between telephone and face-to-face interviews or between telephone and non-telephone households.

APPLICATIONS/CONCLUSIONS

These data provide support that telephone surveys adequately describe energy and protein intakes for a rural, low-income population.

Calcium and magnesium balance in 9-14-y-old children

Few data are available regarding calcium and magnesium absorption and endogenous fecal excretion in children. We used a multitracer stable isotope technique to assess calcium and magnesium balance in 12 boys and 13 girls aged 9-14 y (mean weight: 42 kg) maintained on relatively high calcium intakes (mean: 1310 +/- 82 mg/d). There were no significant differences in absorption of calcium or magnesium from milk between boys and girls. Calcium retention (balance) correlated positively with calcidiol (25-hydroxyvitamin D) concentration (r = 0.48, P = 0.02) and serum alkaline phosphatase activity (r = 0.44, P = 0.03). There was no significant relation between magnesium balance and concentration. When data from this study were combined with our previously reported data, an increase in total calcium absorption was seen for pubertal (Tanner stages 2-4) but not prepubertal (Tanner stage 1) white children over the range of intakes from approximately 750 to 1350 mg/d. Despite intakes similar to the 1989 recommended dietary allowance for magnesium (mean intake: 6.4 +/- 1.2 mg.kg-1.d-1), 11 of the 25 subjects (6 girls and 5 boys) were in negative magnesium balance. We conclude that benefits from higher calcium intakes, < or = 1350 mg/d, were most apparent in pubertal children. In addiction, higher magnesium intakes should be considered for children.

Absorption and tolerance of lactose in infants recovering from severe diarrhea

Nineteen infants were challenged during their convalescence from severe diarrhea with a lactose-containing meal. Twenty-four hour intake, pre- and post-challenge breath H2 levels, clinical responses, and growth were measured at approximately biweekly intervals for 3 months beginning 1 month after hospital discharge. Ten lactose-tolerant infants were assigned randomly to receive one of two formulas similar in composition except for carbohydrates: lactose (Group L) (n = 6) and sucrose (Group S) (n = 4). Infants in Group L had greater intakes and growth rates during the initial 15 days of the study. No difference in weight for age z-scores was detected between groups at the end of the observation period. Infants in Group L had higher baseline and peak breath H2 levels indicating greater colonic carbohydrate fermentation than infants in Group S: however, breath H2 levels were not predictive of tolerance to lactose-containing meals. Carbohydrate absorption by infants in Group S appeared to exceed that of infants in Group L. Thus, colonic fermentation of malabsorbed carbohydrate may have prevented diarrhea and allowed acceptable rates of catch-up growth.