Lisa Harnack

Soft drink consumption among US children and adolescents: Nutritional consequences

OBJECTIVE To determine whether carbonated soft drink consumption is associated with consumption of milk, fruit juice, and the nutrients concentrated in these beverages. DESIGN Data collected as part of the 1994 Continuing Survey of Food Intakes by Individuals were analyzed. Information on food and nutrient intake was derived from 2 days of dietary recall data collected via an in-person interview. SUBJECTS AND PARTICIPANTS Nationally representative sample of people of all ages residing in the United States (response rate = 76.2%). Analyses were restricted to children aged 2 to 18 years (N = 1,810). STATISTICAL ANALYSES PERFORMED Logistic regression analyses were conducted to predict the odds of low milk and juice consumption by soft drink consumption level. To determine whether intake of select nutrients varied by soft drink consumption, multiple linear regression modeling was conducted. Analyses were conducted using sample weights and software appropriate for the survey design. RESULTS Energy intake was positively associated with consumption of nondiet soft drinks. For example, mean adjusted energy intake was 1,830 kcal/day for school-aged children who were nonconsumers of soft drinks compared with 2,018 kcal/day for children in this age group who consumed an average of 9 oz of soda or more per day. Those in the highest soft drink consumption category consumed less milk and fruit juice compared with those in the lowest consumption category (nonconsumers). CONCLUSIONS Nutrition education messages targeted to children and/or their parents should encourage limited consumption of soft drinks. Policies that limit childrens access to soft drinks at day care centers and schools should be promoted.

Fast food restaurant use among women in the Pound of Prevention study: dietary, behavioral and demographic correlates

OBJECTIVE: To examine demographic, behavioral and dietary correlates of frequency of fast food restaurant use in a community-based sample of 891 adult women.DESIGN: A survey was administered at baseline and 3 y later as part of a randomized, prospective intervention trial on weight gain prevention.SUBJECTS: Women (n=891) aged 20–45 y who enrolled in the Pound of Prevention study.MEASUREMENTS: Frequency of fast food restaurant use, dietary intake, demographic and behavioral measures were self-reported. Dietary intake was measured using the 60-item Block Food Frequency Questionnaire. Body weight and height were directly measured.RESULTS: Twenty-one percent of the sample reported eating ≥3 fast food meals per week. Frequency of fast food restaurant use was associated with higher total energy intake, higher percentage fat energy, more frequent consumption of hamburgers, French fries and soft drinks, and less frequent consumption of fiber and fruit. Frequency of fast food restaurant use was higher among younger women, those with lower income, non-White ethnicity, greater body weight, lower dietary restraint, fewer low-fat eating behaviors, and greater television viewing. Over 3 y, increases in frequency of fast food restaurant use were associated with increases in body weight, total energy intake, percentage fat intake, intake of hamburgers, French fries and soft drinks, and with decreases in physical activity, dietary restraint and low-fat eating behaviors. Intake of several other foods, including fruits and vegetables, did not differ by frequency of fast food restaurant use.CONCLUSION: Frequency of fast food restaurant use is associated with higher energy and fat intake and greater body weight, and could be an important risk factor for excess weight gain in the population.

A Randomized School Trial of Environmental Strategies to Encourage Fruit and Vegetable Consumption among Children

The Cafeteria Power Plus project examined whether a cafeteria-based intervention would increase the fruit and vegetable (FV) consumption of children. Twenty-six schools were randomly assigned to either an intervention or control condition. Baseline lunch observations of a sample (N = 1668) of first- and third-grade students occurred in the spring of 2000; follow-up was in the spring of 2002. The intervention took place during two consecutive school years beginning in the fall of 2000 and consisted of daily activities (increasing the availability, attractiveness, and encouragement for FV) and special events (kick-offs, samplings, challenge weeks, theater production, and finale meal). Training of food-service staff and cook managers was ongoing throughout the intervention phase. Students in the intervention schools significantly increased their total fruit intake. Process measures indicated that verbal encouragement by food-service staff was associated with outcomes. The outcomes suggest that multicomponent interventions are more powerful than cafeteria programs alone with this age group.

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 Womens 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.

Effects of calorie labeling and value size pricing on fast food meal choices: results from an experimental trial.

BackgroundAlthough point-of-purchase calorie labeling at restaurants has been proposed as a strategy for improving consumer food choices, a limited number of studies have evaluated this approach. Likewise, little research has been conducted to evaluate the influence of value size pricing on restaurant meal choices.MethodsTo examine the effect of point-of-purchase calorie information and value size pricing on fast food meal choices a randomized 2 × 2 factorial experiment was conducted in which participants ordered a fast food meal from one of four menus that varied with respect to whether calorie information was provided and whether value size pricing was used. Study participants included 594 adolescents and adults who regularly ate at fast food restaurants. Study staff recorded the foods ordered and consumed by each participant. Participants also completed surveys to assess attitudes, beliefs and practices related to fast food and nutrition.ResultsNo significant differences in the energy composition of meals ordered or eaten were found between menu conditions. The average energy content of meals ordered by those randomized to a menu that included calorie information and did not include value size pricing was 842 kcals compared with 827 kcals for those who ordered their meal from a menu that did not include calorie information but had value size pricing (control menu). Results were similar in most analyses conducted stratified by factors such as age, race and education level.ConclusionAdditional research is needed to better evaluate the effects of calorie labeling and value size pricing on fast food meal choices. Studies in which participants are repeatedly exposed to these factors are needed since long term exposure may be required for behavior change.

Effect of point-of-purchase calorie labeling on restaurant and cafeteria food choices: A review of the literature

BackgroundEating away from home has increased in prevalence among US adults and now comprises about 50% of food expenditures. Calorie labeling on chain restaurant menus is one specific policy that has been proposed to help consumers make better food choices at restaurants. The present review evaluates the available empirical literature on the effects of calorie information on food choices in restaurant and cafeteria settings.MethodsComputer-assisted searches were conducted using the PUBMED database and the Google Scholar world wide web search engine to identify studies published in peer-review journals that evaluated calorie labeling of cafeteria or restaurant menu items. Studies that evaluated labeling only some menu items (e.g. low calorie foods only) were excluded from the review since the influence of selective labeling may be different from that which may be expected from comprehensive labeling.ResultsSix studies were identified that met the selection criteria for this review. Results from five of these studies provide some evidence consistent with the hypothesis that calorie information may influence food choices in a cafeteria or restaurant setting. However, results from most of these studies suggest the effect may be weak or inconsistent. One study found no evidence of an effect of calorie labeling on food choices. Each of the studies had at least one major methodological shortcoming, pointing toward the need for better designed studies to more rigorously evaluate the influence of point-of-purchase calorie labeling on food choices.ConclusionMore research is needed that meets minimum standards of methodological quality. Studies need to include behavioral outcomes such as food purchase and eating behaviors. Also, studies need to be implemented in realistic settings such as restaurants and cafeterias.

Cigarette Smoking and Colorectal Cancer Risk by Molecularly Defined Subtypes

BACKGROUND Cigarette smoking is an established risk factor for colorectal cancer. Because colorectal carcinogenesis is a heterogeneous process, we investigated whether cigarette smoking is differentially associated with molecularly defined subtypes of colorectal cancer. METHODS We evaluated associations between smoking and incident colorectal cancer, overall and by microsatellite instability (MSI) phenotype (MSI-high vs MSI-low or microsatellite stable), CpG island methylator phenotype (CIMP positive or CIMP negative), and BRAF mutation status (BRAF mutation positive or BRAF mutation negative), among 37 399 participants in a population-based cohort study (the Iowa Womens Health Study). Cigarette smoking (and other exposures) was assessed by self-report at baseline in 1986, including smoking status (never and ever [former or current]), age at initiation, total duration, average number of cigarettes smoked per day, cumulative pack-years, and induction period. Vital status and state of residence were determined by mailed follow-up questionnaires in 1987, 1989, 1992, and 1997 and by linkage to Iowa death certificate records. Nonrespondents were checked via the National Death Index to identify descendants. Participants with newly diagnosed (ie, incident) colorectal cancer were identified through annual linkage with the Iowa Cancer Registry. Archived paraffin-embedded tumor tissue specimens were obtained for 555 patients with colorectal cancer who were diagnosed from January 1, 1986, through December 31, 2002, and MSI status, CIMP status, and BRAF status were determined. Multivariable Cox regression models were fit to estimate relative risks (RRs) and 95% confidence intervals (CIs). RESULTS Ever-smokers were at moderately increased risk for incident colorectal cancer (RR = 1.19, 95% CI = 1.05 to 1.35) compared with never-smokers. Higher risk estimates were observed for current smokers with MSI-high tumors (RR = 1.99, 95% CI = 1.26 to 3.14), CIMP-positive tumors (RR = 1.88, 95% CI = 1.22 to 2.90), and BRAF mutation-positive tumors (RR = 1.92, 95% CI = 1.22 to 3.02). Other smoking-related variables (ie, age at initiation, total duration, average number of cigarettes smoked per day, cumulative pack-years, and induction period) were also associated with MSI-high, CIMP-positive, and BRAF mutation-positive tumor subtypes. Conversely, cigarette smoking status (ever vs never) was not associated with the MSI-low or microsatellite stable (RR = 1.00, 95% CI = 0.79 to 1.25), CIMP-negative (RR = 1.02, 95% CI = 0.81 to 1.30), or BRAF mutation-negative subtypes (RR = 1.00, 95% CI = 0.65 to 1.27). CONCLUSIONS In this prospective study of older women, cigarette smoking was associated with the MSI-high, CIMP-positive, and BRAF mutation-positive colorectal cancer subtypes, which indicates that epigenetic modification may be functionally involved in smoking-related colorectal carcinogenesis.

Dietary Supplements and Mortality Rate in Older Women

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 Womens 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.

Putting the Whole Grain Puzzle Together: Health Benefits Associated with Whole Grains—Summary of American Society for Nutrition 2010 Satellite Symposium

The symposium “Putting the Whole Grain Puzzle Together: Health Benefits Associated with Whole Grains” sponsored by the ASN brought together researchers to review the evidence regarding the health benefits associated with whole grains. Current scientific evidence indicates that whole grains play an important role in lowering the risk of chronic diseases, such as coronary heart disease, diabetes, and cancer, and also contribute to body weight management and gastrointestinal health. The essential macro- and micronutrients, along with the phytonutrients present in whole grains, synergistically contribute to their beneficial effects. Current evidence lends credence to the recommendations to incorporate whole grain foods into a healthy diet and lifestyle program. The symposium also highlighted the need for further research to examine the role of whole grain foods in disease prevention and management to gain a better understanding of their mechanisms of action.

Dietary catechins and cancer incidence among postmenopausal women: the Iowa Women's Health Study (United States)

Objective: Catechins are bioactive flavonoids present in tea, fruits, and vegetables. Previous epidemiological studies regarding tea and cancer risk were inconclusive, possibly because catechins are also present in other plant foods. We investigated whether a high intake of catechins are associated with cancer incidence among postmenopausal women. Methods: A cohort of 34,651 postmenopausal cancer-free women aged 55–69 years were followed from 1986 to 1998. At baseline, data on diet, medical history, and lifestyle were collected. Incident cancers were obtained through linkage with a cancer registry. Cox proportional hazards analysis was used to estimate risk ratios. Results: After adjustment for potential confounders, catechin intake was inversely associated with rectal cancer incidence only (risk ratios from lowest to highest quartile: 1.00, 0.93, 0.73, and 0.55; p for trend 0.02). Non-significant inverse trends were found for cancer of the upper digestive tract, pancreas, and for hematopoietic cancers. Catechins derived primarily from fruits, (+)-catechin and (−)-epicatechin, tended to be inversely associated with upper digestive tract cancer, whereas catechins derived from tea were inversely associated with rectal cancer. Conclusions: Among several cancers studied, our data suggest that catechin intake may protect against rectal cancer. The distinct effects found for catechins derived from solid foods (fruits) and beverages (tea) may be due to differences in bioavailability or metabolism of the catechins, or to their interactions with other dietary components.