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41.
This review article discusses the Dietary Guidelines for Americans (DGA) in support of a total diet approach to achieving diet and health goals, especially as they relate to the obesity epidemic. However, some scientists and organizations have identified one food, food group, or nutrient as the cause of the obesity epidemic and recommend that simply reducing that food/food group/nutrient will solve the problem. This is simplistic and unlikely to be effective in long term management of the obesity problem. This article also acknowledges discrepancies in the literature and the lack of consensus opinions from systematic reviews. Failure to consider the evidence as a whole can lead to inaccurate reports which may, in turn, adversely influence clinical practice, public policy, and future research. This article also considers where the line should be drawn between individual choice and responsibility and public regulation. Using sugar sweetened beverages as an example, the article considers the lack of a consistent association between added sugars and weight in the literature and calls for policy recommendations that are based on science and emphasizes the need for evidence-based policies rather than policy-based evidence.  相似文献   
42.
The purpose of this study was to examine the association of 100% orange juice (OJ) consumption by children 2 to 18 years of age (n = 7250) participating in the 2003 to 2006 National Health and Nutrition Examination Survey with intakes of select nutrients, MyPyramid food groups, diet quality—measured by the Healthy Eating Index-2005, weight status, and associated risk factors. The National Cancer Institute method was used to estimate the usual intake of 100% OJ consumption, selected nutrients, and MyPyramid food groups. Percentages of the population below the Estimated Average Requirement were determined. Covariate adjusted logistic regression was used to determine if consumers had a lower odds ratio of being overweight or obese. Usual per capita intake of 100% OJ was 1.7 oz/d. Among consumers, the usual intake of 100% OJ for children (n = 2183; 26.2% of population) was 10.2 oz/d. Consumers had higher (P < .05) energy intakes than nonconsumers (9148 ± 113 vs 8625 ± 473 kJ). However, there were no differences in weight or body mass index in consumers and nonconsumers, and there was no significant difference in the risk of being overweight or obese between consumers and nonconsumers (odds ratio, 0.86; 95% confidence interval, 0.70-1.05). Compared with nonconsumers, consumers had a higher (P < .01) percentage (% ± SE) of the population meeting the Estimated Average Requirement for vitamin A (19.6 ± 2.0 vs 30.2 ± 1.4), vitamin C (0.0 ± 0.0 vs 29.2 ± 1.2), folate (1.3 ± 0.3 vs 5.1 ± 0.6), and magnesium (25.5 ± 2.0 vs 39.0 ± 11). The Healthy Eating Index-2005 was significantly (P < .01) higher in consumers (52.4 ± 0.4 vs 48.5 ± 0.3). Consumers also had higher intakes of total fruit, fruit juice, and whole fruit. Moderate consumption of 100% OJ should be encouraged in children as a component of a healthy diet.  相似文献   
43.
Issues involving low calcium intake and dairy product consumption are currently the focus of much debate and discussion at both the scientific and lay community levels. In this review, we examine the following major areas of interest: (1). the role of calcium intake and dairy product consumption in chronic diseases, (2). nutritional qualities of milk and other dairy products, (3). trends in calcium intake and dairy product consumption, (4). current status of calcium intakes and dairy product consumption in children, (5). tracking of calcium intake and diary product consumption, (6). the impact of school meal participation on calcium intake and dairy product consumption, (7). concerns related to calcium-fortified foods and beverages and (8). factors influencing children's milk consumption. To date, the findings indicate that calcium intake and dairy product consumption have beneficial roles in a variety of chronic diseases; dairy products provide an abundant source of vitamins and minerals; calcium intakes of children have increased over time, yet intakes are not meeting the current adequate intake (AI) calcium recommendations; dairy consumption has decreased, and soft drink consumption and, possibly, consumption of calcium-fortified products have increased; consumption of dairy products have a positive nutritional impact on diets of children, particularly from school meals, and there are many factors which influence children's milk consumption, all of which need to be considered in our efforts to promote adequate calcium intakes by children. Based on this review, areas that need immediate attention and future research imperatives are summarized in an effort to further our understanding on what we already know and what we need to know to promote healthier eating habits early in life.  相似文献   
44.
BACKGROUND: Dietary intake and changes in lipoprotein lipids in obese, postmenopausal women placed on an American Heart Association Step 1 diet. OBJECTIVE: The purpose of this study was to determine the specific dietary factors associated with the commonly observed decrease in HDL-C concentration in obese, postmenopausal women placed on a low-fat diet. DESIGN/SUBJECTS/INTERVENTION: Dietary intake, lipoprotein lipid concentrations, and body weight were measured before and after 10 weeks of instruction in the principles of the American Heart Association (AHA) Step 1 diet in 55 overweight and obese (body mass index=33+/-4 kg/m2), sedentary, postmenopausal women (mean age 59+/-5 years). RESULTS: The percent of energy obtained from total fat, monounsaturated, polyunsaturated, saturated fat, and dietary cholesterol decreased significantly after dietary intervention, while the polyunsaturated:saturated ratio and the percent of energy obtained from total carbohydrate, complex carbohydrate, and simple carbohydrate increased. On average, the women lost a small, but significant, amount of body weight (2%+/-3%, P<.0001). Adherence to the AHA diet reduced total cholesterol (-8%+/-8%), LDL-C (-6%+/-11%), and HDL-C (-16%+/-10%). The only dietary change that predicted decreases in HDL-C concentrations was the increase in the percent of energy from simple sugar (r=-0.32, P<.05). There were no relationships between changes in HDL-C and changes in percent of energy from fat (r=0.16), saturated fat (r=0.07), polyunsaturated fat (r=0.04), or monounsaturated fat (r=0.09). APPLICATIONS/CONCLUSIONS: In postmenopausal women, a dietary reduction in total fat, saturated fat, and cholesterol reduces body weight, total cholesterol, and LDL-C, but substitution of simple sugar for dietary fat may lead to a reduction in HDL-C. Further research is needed to determine which specific simple sugars are contributing to diet-induced reductions in HDL-C in older women placed on a low-fat diet.  相似文献   
45.
OBJECTIVE: We evaluated the effects of a preschool nutrition education and food service intervention "Healthy Start," on two-to-five-year-old children in nine Head Start Centers in upstate NY. The primary objective was to reduce the saturated fat (sat-fat) content of preschool meals to <10% daily energy (E) and to reduce consumption of sat-fat by preschoolers to <10% E. METHODS: Six centers were assigned to the food service intervention and three to control condition. Food service intervention included training workshops for cooks and monthly site visits to review progress towards goals. Child dietary intake at preschool was assessed by direct observation and plate waste measurement. Dietary intake at home was assessed by parental food record and telephone interviews. Dietary data were collected each Fall/Spring over two years, including five days of menus and recipes from each center. Dietary data were analyzed with the Minnesota NDS software. RESULTS: Consumption of saturated fat from school meals decreased significantly from 1.0%E to 10.4%E after one year of intervention and to 8.0%E after the second year, compared with an increase of 10.2% to 13.0% to 11.4%E, respectively, for control schools (p < 0.001). Total caloric intake was adequately maintained for both groups. Analysis of preschool menus and recipes over the two-year period of intervention showed a significant decrease in sat-fat content in intervention preschools (from 12.5 at baseline to 8.0%E compared with a change of 12.1%E to >11.6%E in control preschools (p < 0.001)). Total fat content of menus also decreased significantly in intervention schools (31.0% to >25.0%E) compared with controls (29.9% to >28.4%E). CONCLUSIONS: The Healthy Start food service intervention was effective in reducing the fat and saturated fat content of preschool meals and reducing children's consumption of saturated fat at preschool without compromising energy intake or intake of essential nutrients. These goals are consistent with current U.S Dietary Guidelines for children older than two years of age.  相似文献   
46.
OBJECTIVE: To examine if food group consumption varies by differences in socioeconomic, demographic, and lifestyle factors in young adults from a semirural setting in Louisiana. DESIGN: Cross-sectional. SUBJECTS: Young adults (n=1,266, 74% European American, 26% African American; 39% men, 61% women) aged 20 to 38 years, enrolled in the Bogalusa Heart Study. MEASURES: Food group consumption was assessed by a food frequency questionnaire. Socioeconomic (eg, income and education), demographic (eg, age, sex, and ethnicity), and lifestyle (eg, marital status and physical activity) information was obtained by a self-administered questionnaire and the subjects were stratified according to these groups. STATISTICAL ANALYSES: Analysis of covariance (adjusted for covariates) was used to detect differences in the mean servings of food groups consumed per day between the various socioeconomic, demographic, and lifestyle groups. RESULTS: Compared to income$45,000 had lower consumption of burgers/sandwiches (P<0.05) and those with income levels from $30,001 to $45,000 had lower consumption of mixed dishes (P<0.05). Intake of cereals/breads (P<0.05), dairy products (P<0.01), fruits/100% fruit juices (P<0.001), and vegetables (P<0.001) was higher in subjects with >12 years of education. European-American men consumed more servings of dairy products (P<0.05) and sweetened beverages (P<0.05) than African-American men. European-American women consumed more servings of dairy products (P<0.05), vegetables (P<0.05), and fats (P<0.05) than African-American women. African Americans (men and women) consumed more servings of fruits/100% fruit juices (P<0.0001) than European Americans (men and women), respectively. Married individuals consumed more servings of snacks/desserts (P<0.05), but fewer servings of alcoholic beverages (P<0.0001) than those who were unmarried. Active individuals consumed more servings of fruits/100% fruit juices (P<0.05) and fewer servings of burgers/sandwiches (P<0.05) than inactive individuals. CONCLUSIONS: These findings suggest that food group consumption varies by socioeconomic, demographic, and lifestyle factors in young adults from a semirural setting. Food and nutrition professionals who encounter diverse populations need to consider the influence of income, education, sex, ethnicity, marital status, and physical activity on food consumption patterns when planning diets, nutrition education programs, and interventions for young adults.  相似文献   
47.
BACKGROUND: The effect of the recent obesity epidemic on body composition remains unknown. Furthermore, age-related changes in body composition are still unclear. OBJECTIVE: The objective was to simultaneously examine the effects of birth cohort and age on body composition. DESIGN: A total of 1786 well-functioning, community-based whites and blacks (52% women and 35% blacks) aged 70-79 y from the Health, Aging, and Body Composition Study underwent dual-energy X-ray absorptiometry annually from 1997 to 2003. RESULTS: At baseline, mean +/- SD percentage body fat, fat mass, and lean mass (bone-free) were 28 +/- 5%, 24 +/- 7 kg, and 56 +/- 7 kg, respectively, for men and 39 +/- 6%, 28 +/- 9 kg, and 40 +/- 6 kg for women. Mixed models were used to assess the effects of cohort and age-related changes on body composition. Later cohorts in men had a greater percentage body fat (0.32% per birth year, P < 0.0001) than did earlier cohorts. This cohort effect was due to a greater increase in fat mass than in lean mass (0.45 kg and 0.17 kg/birth year, respectively). With increasing age, percentage body fat in men initially increased and then leveled off. This age-related change was due to an accelerated decrease in lean mass and an initial increase and a later decrease in fat mass. Similar but less extreme effects of cohort and age were observed in women. CONCLUSIONS: The combination of effects of both birth cohort and age leads to bigger body size and less lean mass in the elderly.  相似文献   
48.
In the accompanying paper, several tetrahydropyridine analogs of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were screened for their abilities to be oxidized by monoamine oxidase (MAO) to pyridiniums and to produce neurotoxicity in mice. We reported that most of the analogs were oxidized by MAO to pyridiniums and some of the analogs were neurotoxic. We concluded that the capacity of a tetrahydropyridine MPTP analog to be oxidized by MAO to a pyridinium was a necessary, but not sufficient, condition for the compound to be a neurotoxin. In the present paper we attempt to explain further the neurotoxicity or lack of neurotoxicity of these analogs by evaluating the abilities of the pyridinium compounds to serve as substrates for the neostriatal dopamine (DA) transport system and as inhibitors of mitochondrial respiration. We now report that all of the neurotoxic MPTP analogs are oxidized to pyridiniums that are good substrates for the neostriatal DA carrier and good inhibitors of mitochondrial respiration. The results are consistent with an important role for both uptake of the pyridiniums by the DA carrier and inhibition by the pyridiniums of mitochondrial respiration in the neurotoxicity induced by MPTP and its analogs.  相似文献   
49.
50.
Gimme 5: A Fresh Nutrition Concept for Students (Gimme 5) was a 4-year intervention targeting increased fruit and vegetable consumption by high school students. Twelve schools were randomized to intervention or control conditions. The cohort (2,213 students; 56% female, 84% Euro-American) were followed from 9th to 12th grade. Interventions were composed of a school-based media campaign, classroom workshops, school meal modification, and parental involvement. For each of the four Gimme 5 intervention components, process evaluation measures were developed to assess program dose, penetration, and utilization, as well as external competing factors. Process evaluation results are presented to illustrate the various functions of process evaluation data. These include, but are not limited to, describing program implementation, quality control and monitoring, and explaining study outcomes. The implementation of process evaluation systems to complement the outcome measures in a high school-based intervention provides useful strategies for a more comprehensive approach to program evaluation.  相似文献   
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