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Lisa Harnack

Publications and source records attributed to Lisa Harnack.

29 records · Page 2Linked to original sources
PubMed2004

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.

Child↗
PubMed2003

Impact of the Pathways intervention on dietary intakes of American Indian schoolchildren.

BACKGROUND: The Pathways study was a randomized, 3-year trial of obesity prevention in American Indian Children. An important goal of the Pathways intervention was to significantly decrease the percentage of calories eaten as fat by the intervention children, relative to controls. This paper reports the effects of the Pathways intervention on dietary intake. METHODS: Two types of dietary data were analyzed from random samples of children in 41 schools: direct observation of school lunch intake at baseline (2nd grade) and follow-up (5th grade) (n=470), and 24-hour dietary recalls at follow-up only (n=620). Nutrient contents of school meals and recalls were calculated by NDS and NDS-R software (University of Minnesota), using vendor products and recipes from each school. RESULTS: Based on lunch observations, the intervention was associated with significant decreases in mean percentage of calories from total fat (3.6%) and saturated fat (2.1%) relative to controls, and a significant increase in the percentage of calories from total carbohydrate (3.7%). Compared with the control children, intervention children reported significantly smaller 24-hour intakes of energy (263 kcal), protein (9.5 g), total fat (15.1 g), saturated fat (6.0 g), and polyunsaturated fat (2.3 g); and as a percent of calories, total fat (2.5%) and saturated fat (1.1%). Mean intake of carbohydrates as a percentage of calories was significantly greater in intervention children by 2.5%, compared with controls. CONCLUSIONS: The Pathways intervention successfully reduced the intake of percent calories from fat and saturated fat, at school lunch and over the whole day.

Child↗
PubMed2003

The effects of the Pathways Obesity Prevention Program on physical activity in American Indian children.

BACKGROUND: Inadequate opportunities for physical activity at school and overall low levels of activity contribute to the high prevalence of overweight and obesity in American-Indian children. METHODS: A school-based physical activity intervention was implemented which emphasized increasing the frequency and quality of physical education (PE) classes and activity breaks. Changes in physical activity were assessed using the TriTrac-R3D accelerometer in a subsample of 580 of the students (34%) randomly selected from the Pathways study cohort. Baseline measures were completed with children in second grade. Follow-up measurements were obtained in the spring of the fifth grade. RESULTS: Intervention schools were more active (+6.3 to +27.2%) than control schools at three of the four sites, although the overall difference between intervention and control schools (approximately 10%) was not significant (P>0.05). Boys were more active than girls by 17 to 21% (P < or =.01) at both baseline and follow-up. CONCLUSIONS: Despite the trend for greater physical activity at three of four study sites, and an overall difference of approximately 10% between intervention and control schools, high variability in accelerometer AVM and the opportunity to measure physical activity on only 1 day resulted in a the failure to detect the difference as significant.

Anthropometry↗
PubMed2003

Dietary intake and food sources of whole grains among US children and adolescents: data from the 1994-1996 Continuing Survey of Food Intakes by Individuals.

OBJECTIVE: This study characterizes whole grain consumption among a nationally representative sample of US children and adolescents. DESIGN: Data used in this study were collected as part of the 1994-1996 US Department of Agriculture Continuing Survey of Food Intakes by Individuals (CSFII). SUBJECTS/SETTING: CSFII was designed to obtain a nationally representative sample of noninstitutionalized persons of all ages residing in the United States. Analyses reported in this article are limited to participants aged 2 to 18 years with two days of dietary recall data (n=4,802). Foods reported in the survey were quantified in servings as defined by the Food Guide Pyramid using the US Department of Agriculture Pyramid Servings Database, which contains reference data for each food reported in CSFII in servings per 100 g for 30 Pyramid food groups, including whole grain and total grain. STATISTICAL ANALYSES: Means, frequencies, and logistic regression analyses were conducted as appropriate. RESULTS: Average whole grain intake ranged from 0.8 servings per day for preschool-aged children to 1.0 servings per day for adolescents. Ready-to-eat cereals, corn and other chips, and yeast breads were found to be the major food sources of whole grains accounting for 30.9%, 21.7%, and 18.1% of whole grain intake respectively among those aged two to 18 years. APPLICATIONS/CONCLUSIONS: Given the apparent low level of whole grain intake among most children and adolescents in the United States, interventions are needed to increase intake of whole-grain foods.

Adolescent↗
PubMed2003

Trends in the trans-fatty acid composition of the diet in a metropolitan area: the Minnesota Heart Survey.

OBJECTIVE: In this study, we examine trends in dietary intake of trans-fatty acids from 1980-1982 to 1995-1997 using data collected as part of the Minnesota Heart Survey (MHS). DESIGN: The MHS is an ongoing observational epidemiologic study among independent cross-sectional probability samples of adults. Twenty-four-hour dietary recalls were collected on a subset of participants. To obtain trans-fatty acid intake estimates, the dietary recall records were recalculated using the University of Minnesota Nutrition Coordinating Center Food and Nutrient Database. Subjects/setting The survey population included noninstitutionalized adults aged 25 to 74 years residing in the Minneapolis-St. Paul, MN, metropolitan area. Statistical analysis Mean intake estimates were generated for each survey, and a generalized linear mixed model was used to test the null hypothesis of no difference in the age-adjusted sex-specific means between 1980-1982, 1985-1987, 1990-1992, and 1995-1997. RESULTS: Downward trends in dietary intake of trans-fatty acids were found between 1980-1982 and 1995-1997. For example, for men mean intake of total trans-fatty acids declined from 8.3 g per day in 1980-1982 to 6.2 g per day in 1995-1997 (P<.001). Represented as a percentage of energy, similar declines were seen with mean intake of total trans-fatty acids decreasing from 3.0% of total energy in 1980-1982 to 2.2% of total energy in 1995-1997 (P<.001). APPLICATIONS/CONCLUSIONS: It seems that intake of trans-fatty acids is on the decline. Consideration should be given to additional changes in the food supply and consumer food choices that may result in further reduction in consumption of trans-fatty acids.

Adult↗
PubMed2003

Glycemic index, glycemic load, and incidence of endometrial cancer: the Iowa women's health study.

Although specific foods or nutrients have not been linked consistently with risk of endometrial cancer, obesity and diabetes are associated with increased risk. These conditions may be influenced by the glycemic index or load of the usual diet. We therefore examined the association of glycemic index and load measured at baseline using a food frequency questionnaire in a cohort of 23335 postmenopausal women. Over 15 yr of follow-up, we identified 415 incident endometrial cancers. The average glycemic index was not associated with endometrial cancer occurrence. After adjustment for other risk factors, the average glycemic load was positively but weakly associated, with a relative risk of 1.24 (95% CI = 0.90-1.72) for the highest versus lowest quintile of glycemic load (P for trend = 0.08). This relative risk was 1.46 (95% CI = 1.02-2.08; P for trend = 0.02) among nondiabetic women, but the trend was in the opposite direction among diabetic women. Our study indicates that a higher dietary glycemic load may be a risk factor for endometrial cancer incidence in nondiabetic women.

Age Factors↗
PubMed2002

Meat intake and cooking techniques: associations with pancreatic cancer.

Heterocyclic amines (HCAs), and polycyclic aromatic hydrocarbons (PAHs), formed in temperature and time-dependent manners during cooking of meat, may increase the risk of certain cancers. As these compounds could be carcinogenic for the pancreas, we assessed meat intake, preparation methods, and doneness preferences as risk factors for exocrine pancreatic cancer. In a case-control study (cases=193, controls=674), subjects provided information on their usual meat intake and how it was cooked, e.g. fried, grilled or barbecued (BBQ), etc. Meat doneness preferences were measured using photographs that showed internal doneness and external brownness with a numerical scale. Data were analyzed with unconditional logistic regression. Odds ratios (ORs) increased with increased intake of grilled/BBQ red meat in an analysis adjusted for age, sex, smoking, education, race, and diabetes. Based on amount of BBQ meat consumed, the OR and 95% confidence interval (CI) for the fifth quintile relative to the reference group (quintiles 1 and 2) was 2.19 (1.4, 3.4). Findings were not substantively changed by further adjustment for calories, total fat, fruit and vegetables, or alcohol consumption (from a food frequency questionnaire (FFQ)). Other meat variables did not show statistically significant associations with risk nor did they substantively alter the findings for BBQ. These included total meat, processed meat, total red meat, total white meat, total broiled meat, total fried meat, or total meat cooked by means other than grilling. We conclude that grilled red meat intake is a risk factor for pancreatic cancer and that method of meat preparation in addition to total intake is important in assessing the effects of meat consumption in epidemiologic studies.

Adult↗
PubMed2002

An evaluation of the Dietary Guidelines for Americans in relation to cancer occurrence.

BACKGROUND: Although scientific knowledge regarding the influence of nutritional factors on health and disease serves as the basis for specific recommendations included in the Dietary Guidelines for Americans, limited empirical epidemiologic data are available to verify that adherence to the cluster of nutrition-related behaviors included in the Dietary Guidelines will reduce the incidence of disease. OBJECTIVE: We examined the association of compliance with the Dietary Guidelines and incident cancers. DESIGN: Data from a population-based cohort of postmenopausal women (n = 34 708) were examined. A dietary guidelines index was derived as a summary measure of compliance with the Dietary Guidelines, and the association of this index and cancer incidence was examined for all cancers combined and for site-specific cancers with > 100 events. RESULTS: For all cancers combined, the relative risks associated with the upper 4 quintiles of the dietary guidelines index in reference to the bottom quintile were 0.95 (95% CI: 0.87, 1.05) for quintile 2, 0.88 (95% CI: 0.80, 0.97) for quintile 3, 0.88 (95% CI: 0.80, 0.96) for quintile 4, and 0.85 (95% CI: 0.77, 0.93) for quintile 5 (P for trend < 0.01). Similar patterns in relative risks were found for cancers of the colon, bronchus and lung, breast, and uterus. In contrast, ovarian cancer incidence was positively associated with the dietary guidelines index. CONCLUSION: Our findings suggest that adherence to the cluster of nutrition-related behaviors included in the Dietary Guidelines for Americans may be associated with a lower risk of cancer.

Age Factors↗
PubMed2002

Relationship of folate, vitamin B-6, vitamin B-12, and methionine intake to incidence of colorectal cancers.

It is hypothesized that diets deficient in folate, methionine, and vitamins B-6 and B-12 cause DNA hypomethylation and, as a result, increase risk of colorectal cancers. Furthermore, it is proposed that alcohol, a methyl group antagonist, increases risk of colorectal cancers among those with low intake of folate. Data from the Iowa Women's Health Study, a population-based cohort of incident cancer, were used to examine the relationship of folate, methionine, and vitamins B-6 and B-12 to occurrence of cancers of the colon (n = 598) and rectum (n = 123) over 13 yr of follow-up. There were no independent associations of folate, methionine, or vitamins B-6 and B-12 derived from a food frequency questionnaire with incidence of colon cancer. Adjusted relative risks (RRs) of rectal cancer were similar across categories of folate, vitamin B-12, and methionine intake, but RRs increased progressively with increasing intake of vitamin B-6 [P (for trend) = 0.03]. RRs suggested that incidence of cancer of the proximal colon was lower among those with 1) high folate and high vitamin B-12 intake [RR = 0.59, 95% confidence interval (CI) = 0.39-0.89] and 2) high folate and high vitamin B-6 intake (RR = 0.65, 95% CI = 0.50-0.84) than among those with the lowest intake of these nutrients. Incidence of cancer of the proximal colon was also somewhat lower among those with high folate and low alcohol intake (RR = 0.44, 95% CI = 0.22-0.89). Findings provide limited support for an association between dietary factors involved in DNA methylation and risk of cancers of the colon and rectum.

Aged↗