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The effects of child formula toothpastes on enamel caries using two in vitro pH-cycling models.

AIMS/OBJECTIVES: To compare, using two pH-cycling models, the de/remineralisation effects of children's toothpastes on primary teeth. DESIGN: In vitro single-section and pH-cycling models. METHODS: Primary teeth were placed in demineralising solution for 96 hours to produce artificial carious lesions 60-100 microm deep. They were cut into 100 microm thick sections and assigned to 6 groups. Sections in Groups A and D were exposed to a non-fluoridated toothpaste, those in Groups B and E to half-pea-sized (0.16g) and those in Groups C and F to pea-sized portions (0.32g) of a 500ppm F toothpaste. pH-cycling Model I (Groups A, B, C), without added fluoride, ran for 7 days, while Model II (Groups D, E, F), with 0.25ppm F, ran for 10 days. OUTCOME MEASUREMENTS: Lesions were evaluated using polarised light microscopy and microradiography. RESULTS: Lesions in Groups B and E progressed by 64% and 61%, respectively, while those in Groups C and F progressed by only 19% and 23% respectively. CONCLUSIONS: Both 10-day and 7-day pH-cycling models were suitable for studying carious lesion progression in primary teeth (the demineralising and remineralising solutions of the 10-day cycling model contained 0.25ppm F). A pea-sized portion (0.32g) of 500ppm F toothpaste slowed down the demineralisation progression better than a half-pea-sized portion.

Cariostatic Agents↗

Improving food frequency questionnaires: a qualitative approach using cognitive interviewing.

In an attempt to improve data quality and ease of administration of standard self-administered food frequency questionnaires, various alternative approaches were tried for inquiring about frequency of consumption, portion size, seasonal intake, and food preparation. Evaluation consisted of a cognitive interviewing method in which respondents verbalize their thought process while completing several variations of a questionnaire. Interviewers observed and asked follow-up probe questions to evaluate problems or inconsistencies verbalized by respondents. Consensus and judgment by interviewers and observers suggested several problematic features of food frequency questionnaires: formatting of questions about frequency and portion size; computing average frequencies for aggregated food items or for foods eaten seasonally; comprehension of many items; and ordering of foods. These findings led to cognitive refinement and innovations, which included detailed questions regarding preparation or use of low-fat varieties or other alternatives to help better describe specifics of intake for some foods; questions on seasonal intake for several foods; inclusion of portion size ranges; and additional response categories for frequency of intake. Cognitive interviewing is an important step in pinpointing cognitive problems in dietary questionnaires.

Aged↗

Digital photography: a new method for estimating food intake in cafeteria settings.

OBJECTIVE: The primary objective of this study was to test the comparability of digital photography and visual estimation procedures for estimating food intake. RESEARCH METHODS AND PROCEDURES: The study sample included 71 breakfast meals and 59 lunch meals eaten in a university cafeteria during a single day. A total of 66 different foods were employed as test foods that could be selected by the students. Food selections and plate waste, as estimated by digital photography and visual estimation, were compared. For digital photography, three observers independently estimated portion sizes of each food item based upon digital photographs. One observer estimated portion sizes in the cafeteria setting, using visual estimation, a method that has been validated in other studies. RESULTS: To test the accuracy of the two procedures for measuring food intake, the estimates of food weights derived from both procedures were compared using Bland-Altman regression. In comparison to visual estimation, the digital photography method yielded comparable estimates of food selections, plate waste, and total food intake for seven of nine comparisons. The two methods of estimating food portions yielded comparable results for most (78%) types of foods. The two methods also yielded similar variability. DISCUSSION: These findings suggest that the digital photography method is an alternative to the traditional method of estimating food intake via direct observation.

Energy Intake↗

The financial reality of overeating.

OBJECTIVE: Obesity has been linked to frequency of meals eaten outside the home and the associated large portion sizes. These large portions, which have been shown to promote overeating, are often offered for a small additional cost which may appear economical to the consumer. The aim of this study was to calculate additional costs from medical, gasoline, and increased caloric needs that result from weight gain attributable to overeating and thus provide consumers with added incentive not to upsize their meal, or overeat in general. METHODS: The effects and costs of overeating were estimated for men and women with a BMI of 22.5, 27.5, and 32.5 by conducting a Pubmed search for relevant literature combined with US statistics obtained from open Federal and other websites. RESULTS: Among fast food restaurants, the average upsized meal increases energy content of the meal from 927 to 1324 kcal at an added cost of Dollar 0.67. Because the regular meal is already 37% of a 2500 kcal diet, the extra energy of upsizing is likely to be in excess of need and thus potentially stored as 36 grams of added adipose tissue. This hypothesized weight gain predicts an average increase auto fuel cost by Dollar 0.05 for both men and women, maintenance food cost by Dollar 0.36 and Dollar 0.35 for men and women, respectively, and health care cost from Dollar 0.82 to Dollar 6.64. CONCLUSIONS: These calculated costs exceed the value of upsized meals and may provide motivation to some consumers not to upsize their meals. The same rationale can be applied to other environments notorious for encouraging overeating. Thus, this information could be presented to individuals along with other more well publicized health risks and consequences during weight control counseling.

Costs and Cost Analysis↗

A data-based approach to diet questionnaire design and testing.

A self-administered diet history questionnaire has been developed for epidemiologic and clinical use. Both the food list and the nutrient values to be associated with it were developed using dietary data from 11,658 adult respondents to the Second National Health and Nutrition Examination Survey (NHANES II). Food items were selected on the basis of their contribution to total population intake of energy and each of 17 nutrients in the NHANES II data, and represent over 90% of each of those nutrients. Associated nutrient composition values were determined from the NHANES II database using frequency of consumption data in that survey. Portion sizes to be associated with each food item were derived from observed portion size distributions in NHANES II, based on three-dimensional models. The resulting food list and its corresponding brief data base, when used to calculate nutrients from a diet record, yielded correlations of r greater than 0.70 with the more detailed method. Field administration produced mean values comparable to national data.

Adult↗

[Assessment of the food list and serving size of a Food Frequency Questionnaire in an adult population].

This study examined both the food list and portion size values from a Food Frequency Questionnaire (FFQ) among participants in a case-control study in São Paulo, Brazil. Two hundred adult respondents to a case-control study were randomly selected (101 men and 99 women; age range: 35-69 years). FFQ food items were examined on the basis of their contribution to total population nutrient intake estimated by 24-hour dietary recall (1-DR). We examined the frequency distribution of equivalent-gram weights of each selected food from the 1-DR and identified the portion sizes as small, medium, and large in the distribution (percentiles 25, 50, and 75, respectively). The FFQ provided close estimation of total fat, saturated fatty acids, cholesterol, total fiber, vitamin B6, and folic acid compared to the 1-DR (paired t-test; p < 0.05). The FFQ food list covered the study population's main dietary nutrient sources.

Adult↗

Comparison of two dietary questionnaires validated against multiple dietary records collected during a 1-year period.

The validity of two dietary history questionnaires was examined, one the Health Habits and History Questionnaire (HHHQ) developed by Block et al and the other a questionnaire developed by investigators at the University of Michigan (UM). The reference data consisted of the mean of four 4-day dietary records and recalls collected for 1 year before administration of the questionnaires. The sample of 85 persons included black and white men and women aged 25 to 50 years. The HHHQ was entirely self-administered; the UM questionnaire had both self- and interviewer-administered components. The HHHQ group means were similar to food record estimates for energy and most nutrients, whereas the UM questionnaire produced overestimates for energy and all nutrients examined. Correlations ranged from .31 to .60 (median = .48) for the UM questionnaire and from .42 to .68 (median = .57) for the HHHQ. Use of respondent-reported portion sizes with the HHHQ produced higher correlations than use of investigator-determined "standard" portion sizes (median r = .43 vs .57). Food frequency questionnaires can provide useful nutrient data for individuals as well as groups.

Adult↗

Effects of cooking on radiocesium in fish from the Savannah River: exposure differences for the public.

Understanding the factors that contribute to the risk from fish consumption is an important public health concern because of potential adverse effects of radionuclides, organochlorines, other pesticides, and mercury. Risk from consumption is normally computed on the basis of contaminant levels in fish, meal frequency, and meal size, yet cooking practices may also affect risk. This study examines the effect of deep-frying on radiocesium (137Cs) levels and risk to people fishing along the Savannah River. South Carolina and Georgia have issued consumption advisories for the Savannah River, based partly on 137Cs. 137Cs levels were significantly higher in the cooked fish compared to the raw fish on a wet weight basis. Mean 137Cs levels were 0.61 pCi/g (wet weight basis) in raw fish, 0.81 pCi/g in cooked-breaded, and 0.99 pCi/g in cooked-unbreaded fish. Deep-frying with and without breading resulted in a weight loss of 25 and 39%, while 137Cs levels increased by 32 and 62%, respectively. Therefore, the differences were due mainly to weight loss during cooking. However, the data suggest that risk assessments should be based on cooked portion size for contaminant analysis, or the risk from 137Cs in fish will be underestimated. People are likely to estimate the amounts of fish they eat based on a meal size of the cooked portion, while risk assessors determine 137Cs levels in raw fish. A conversion factor of at least two for 137Cs increase during cooking is reasonable and conservative, given the variability in 137Cs levels. The data also suggest that surveys determining consumption should specifically ask about portion size before or after cooking and state which was used in their methods.

Animals↗

Development of a food frequency questionnaire (FFQ) for an elderly population based on a population survey.

Older people have different eating patterns than their younger counterparts, although in most nutritional studies of older populations, food frequency questionnaires (FFQ) that were developed and validated for the general adult population are used. In this paper, we present the advantages of developing an FFQ for an older population based on a population survey. A random sample of the Negev's (Southern Israel) Jewish population > or = 35 y old was recruited and interviewed for their dietary intake using 24-h recalls. Foods eaten were aggregated into conceptually similar groups and entered into stepwise regression models to predict variation in nutrient intake. We interviewed 796 people age 35-64 y and 377 people > or = 65 y old for the study. Significantly more items were required to reach 80% between-person variability for zinc, magnesium, vitamin E and protein for the elderly compared with the younger age group. Portion sizes of most items consumed by the elderly were smaller compared with the Israeli Ministry of Health portion sizes booklet and the younger age group's intake estimates. The nutrient values assigned for each line based on a weighted mean of the intake of the elderly were different from those using the most frequently used item. The above findings highlight some of the advantages of developing an FFQ for an older population based on a population survey. Further studies are required to compare the validity of existing tools adapted for the elderly to those developed on the basis of population surveys.

Adult↗

Determination of glycaemic index; some methodological aspects related to the analysis of carbohydrate load and characteristics of the previous evening meal.

OBJECTIVES: To determine the possible differences in glycaemic index (GI) depending on (1) the analytical method used to calculate the 'available carbohydrate' load, that is, using carbohydrates by difference (total carbohydrate by difference, minus dietary fibre (DF)) as available carbohydrates vs available starch basis (total starch minus resistant starch (RS)) of a food rich in intrinsic RS and (2) the effect of GI characteristics and/or the content of indigestible carbohydrates (RS and DF) of the evening meal prior to GI testing the following morning. DESIGN: Blood glucose and serum insulin responses were studied after subjects consuming (1) two levels of barley kernels rich in intrinsic RS (15.2%, total starch basis) and (2) after a standard breakfast following three different evening meals varying in GI and/or indigestible carbohydrates: pasta, barley kernels and white wheat bread, respectively. SUBJECTS: Healthy adults with normal body mass index. RESULTS: (1) Increasing the portion size of barley kernels from 79.6 g (50 g 'available carbohydrates') to 93.9 g (50 g available starch) to adjust for its RS content did not significantly affect the GI or insulin index (11). (2) The low GI barley evening meal, as opposed to white wheat bread and pasta evening meals, reduced the postprandial glycaemic and insulinaemic (23 and 29%, respectively, P < 0.05) areas under the curve at a standardized white bread breakfast fed the following morning. CONCLUSION: (1) Increasing portion size to compensate for the considerable portion of RS in a low GI barley product had no significant impact on GI or II. However, for GI testing, it is recommended to base carbohydrate load on specific analyses of the available carbohydrate content. (2) A low GI barley evening meal containing high levels of indigestible carbohydrates (RS and DF) substantially reduced the GI and II of white wheat bread determined at a subsequent breakfast meal.

Adult↗

Why should we study human food intake behaviour?

Several aspects of human eating behaviour may be relevant for identifying effective measures to treat or prevent diseases like obesity, diabetes, or the metabolic syndrome, whose natural history is strongly influenced by nutritional factors. Physiological factors determine hunger, satiety and satiation, and a biological learning mechanism supports the acquisition of food likes and dislikes. The paradigm of "conditioned taste aversion" refers to the acquisition of a strong rejection response after the intake of a food has been followed by digestive disorder. Food likes are acquired following the experience of the beneficial post-ingestive effects of intake. Physiological mechanisms reinforce the liking for energy-rich foods and both environmental and biological conditions facilitate "passive overconsumption". Sensory factors are important determinants of appetite and food choices from birth to old age. The human newborn exhibits an innate repertoire of acceptance or rejection for taste substances. The progressive change of sensory functions associated with ageing affects appetite and the pleasure of eating. Many individual psychological characteristics affect food intake behaviour in a significant way. These include chronic dietary restraint, disinhibition, etc. These psychological traits can be objectively assessed using validated psychometric instruments. Various stimuli present in the environment also affect ingestive behaviours in humans. Portion size is one potent environmental determinant of how much a person eats, regardless of hunger. The general increase in portion sizes observed in North America over the last decades might have played an important role in the rapid rise of obesity prevalence. Socio-economic factors also affect food selection and food intake in human societies. Factors such as education level and income determine food choices and behaviours in a way that does affect the risk of obesity. Behavioural science has provided many insights about crucial cause-and-effect relationships that affect nutrition and health. Therefore, clinicians and nutritionists cannot neglect this important area if they wish to effectively modify the habitual diet of individual patients or the general population.

Appetite↗

Common genetic variations in CCK, leptin, and leptin receptor genes are associated with specific human eating patterns.

Obesity has a heritable component; however, the heterogeneity of obesity complicates dissection of its genetic background. In this study, we therefore focused on eating patterns as specific traits within obesity. These traits have a heritable component; genes associated with a specific eating pattern have not yet been reported at the population level. In this study, we determined whether genetic variations in cholecystokinin (CCK) and leptin genes underlie specific eating patterns. We selected obese individuals showing extreme snacking behavior or use of excessive portion sizes from a large population-based sample (n = 17,357) from the Prospect-EPIC (European Prospective Study into Cancer and Nutrition) study. Using allele-specific PCRs, we tested several single nucleotide polymorphisms in the candidate genes and performed haplotype analysis. Obese carriers of common allelic variations in leptin or the leptin receptor gene had an increased risk to display extreme snacking behavior. In contrast, obese carriers of common allelic variations in CCK had an increased risk to eating increased meal sizes. In conclusion, we identified common allelic variants specifically associated with distinctly different eating patterns, namely extreme snacking behavior or excessive portion size.

Aged↗

Validity and reproducibility of a quantitative food frequency questionnaire for a cohort study in Japan.

BACKGROUND: A self-administered quantitative food frequency questionnaire (Qx) was developed for a population-based cohort study on cancer in Takayama, Japan. METHODS: The Qx was tested among 58 male and 59 female volunteers. Average daily nutrient intakes for the previous year calculated from the Qx were compared with those from 3-day food records and four 24-h recalls. The Qx was also validated among 37 volunteers by comparing the nutrient intakes calculated from the Qx with 12 1-day food records during a year. We also calculated the intra-class correlation coefficients for various nutrients between the Qx and the second Qx administered by the same volunteers 1 year after the first survey. RESULTS: Pearson correlation coefficients between total energy from the Qx and 3-day records were 0.38 for men and 0.25 for women and those between the Qx and 24-h recalls were 0.19 and -0.02 for men and women, respectively. Correlations between the several nutrients from the Qx and 3-day records ranged from 0.2 to 0.5 for both men and women. These correlations after energy adjustment ranged from 0.2 to 0.6 for men and from 0.1 to 0.7 for women. In general, the correlations for various nutrients between the Qx and 12 1-day records were higher than those described above. The intra-class correlation coefficients ranged from 0.46 to 0.78 in men and from 0.36 to 0.67, except for vitamin C in women. When the information on portion size was excluded, almost all of the above indices showed somewhat lower figures. CONCLUSION: These results suggest that our food frequency questionnaire with portion size information can be used to estimate nutrient intakes of each individual.

Adult↗

An examination of the trade-offs in public health resulting from the use of default exposure assumptions in fish consumption advisories.

Efforts to provide for public health protection from environmental contaminants in fish have resulted in various advisories or recommendations with regard to fish consumption from local, state, and federal agencies. These advisories are based on measured levels of contaminants in fish that are combined with values for body weight and portion size to produce an estimate of an "acceptable" consumption frequency (e.g., eat no more than once per month). Because values for body weight and portion size are generally generic default values, they do not necessarily relate to a specific population or to any individual in that population. Thus, the use of default values may result in underprotection or overprotection in any given case. Given the benefits of fish consumption and the risks from overexposure to various toxicants, vigilance is required by custodians of public health to ensure that populations are protected while being cautious not to over- or underprotect them. In this analysis, we examine the "acceptable" consumption limits derived for fish species/groups consumed by three specific populations and determine the extent of public health protection afforded by these limits. To accomplish this, the "acceptable" consumption frequencies are derived based, in part, on default assumptions and are compared to intakes calculated from empirically derived species-specific individual consumption and demographic data. Sensitivity analyses and population-specific probabilistic assessments of exposure are conducted to identify those values and/or assumptions which might significantly influence the resulting fish consumption advisories. Three populations were chosen for study based on their ability to represent populations of greatest concern: those most sensitive and/or those most exposed. We conclude from this investigation that consumption pattern data, contaminant data and body weight data together can be used to make fish consumption advisories more focused and, therefore, less likely to be under- or overprotective.

Animals↗

Is shorter always better? Relative importance of questionnaire length and cognitive ease on response rates and data quality for two dietary questionnaires.

In this study, the authors sought to determine the effects of length and clarity on response rates and data quality for two food frequency questionnaires (FFQs): the newly developed 36-page Diet History Questionnaire (DHQ), designed to be cognitively easier for respondents, and a 16-page FFQ developed earlier for the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. The PLCO Trial is a 23-year randomized controlled clinical trial begun in 1992. The sample for this substudy, which was conducted from January to April of 1998, consisted of 900 control and 450 screened PLCO participants aged 55-74 years. Controls received either the DHQ or the PLCO FFQ by mail. Screenees, who had previously completed the PLCO FFQ at baseline, were administered the DHQ. Among controls, the response rate for both FFQs was 82%. Average amounts of time needed by controls to complete the DHQ and the PLCO FFQ were 68 minutes and 39 minutes, respectively. Percentages of missing or uninterpretable responses were similar between instruments for questions on frequency of intake but were approximately 3 and 9 percentage points lower (p < or = 0.001) in the DHQ for questions on portion size and use of vitamin/mineral supplements, respectively. Among screenees, response rates for the DHQ and the PLCO FFQ were 84% and 89%, respectively, and analyses of questions on portion size and supplement use showed few differences. These data indicated that the shorter FFQ was not better from the perspective of response rate and data quality, and that clarity and ease of administration may compensate for questionnaire length.

Aged↗

Comparison of dietary assessment methods in nutritional epidemiology: weighed records v. 24 h recalls, food-frequency questionnaires and estimated-diet records.

Women (n 160) aged 50 to 65 years were asked to weigh their food for 4 d on four occasions over the period of 1 year, using the PETRA (Portable Electronic Tape Recorded Automatic) scales. Throughout the year, they were asked to complete seven other dietary assessment methods: a simple 24 h recall, a structured 24 h recall with portion size assessments using photographs, two food-frequency questionnaires, a 7 d estimated record or open-ended food diary, a structured food-frequency (menu) record, and a structured food-frequency (menu) record with portion sizes assessed using photographs. Comparisons between the average of the 16 d weighed records and the first presentation of each method indicated that food-frequency questionnaires were not appreciably better at placing individuals in the distribution of habitual diet than 24 h recalls, due partly to inaccuracies in the estimation of frequency of food consumption. With a 7 d estimated record or open-ended food diary, however, individual values of nutrients were most closely associated with those obtained from 16 d weighed records, and there were no significant differences in average food or nutrient intakes.

Diet Records↗

Identification of optimal ranges in ribeye area for portion cutting of beef steaks.

Restaurant-ready (21-d aged, needle tenderized) loin steaks (strip, S; and T-bone, TB) representing three portion sizes (227, 284, and 340 g for S; 397, 454, and 510 g for TB) were portioned from 71 low-Choice beef carcasses representing seven ribeye size groups (70.9 cm2 and less to 103.2 cm2 and greater, in 6.3-cm2 increments). Steaks (n = 568) were cooked on a grooved grill to temperatures of either 67 or 77 degrees C and evaluated for cooking characteristics, sensory attributes (n = 284), and shear force (n = 284) to identify optimal ribeye areas for portioned steaks. As expected, thickness of all portioned steaks decreased (P < .05) as ribeye size increased, whereas thickness of steaks increased (P < .05) as portion size increased. The S were significantly thicker than TB. The TB cooked faster (P < .05) than did S for ribeye areas 77.4 to 83.8 cm2 in the average portion sizes and for ribeye areas 71.0 to 96.6 cm2 in the large portion sizes. However, S cooked significantly faster than did TB for ribeye areas less than 70.9 cm2 in the average portion sizes. The S had higher (P < .05) initial tenderness scores and lower (P < .05) shear values than did TB. Initial tenderness scores were lower (P < .05) for ribeye areas greater than 103.2 cm2 compared with ribeye areas less than 83.8 cm2 and 90.3 to 96.6 cm2, with all others being intermediate. Shear force tended (P = .08) to follow the initial tenderness results. The S cooked to both end point temperatures, and TB cooked to 67 degrees C had higher (P < .05) initial tenderness scores than did TB cooked to 77 degrees C. Tenderness was reduced in TB cooked to higher temperatures as well as in S and TB portioned from ribeye areas greater than 103.2 cm2. Steaks portioned from carcasses with ribeye areas between 77.4 to 96.6 cm2 can optimize both cooking time and tenderness for the foodservice sector.

Animals↗

Optimizing oral nutritional drink supplementation in patients with chronic obstructive pulmonary disease.

Nutritional support is indicated in some patients with chronic obstructive pulmonary disease to restore nutritional status and improve functional capacity. However, the efficacy of nutritional supplements is sometimes disappointing, partly owing to a compensatory drop in habitual food intake. We retrospectively studied the effect of nutritional drink supplements, differing in portion size and energy content, on weight gain and body composition. Thirty-nine patients with stable chronic obstructive pulmonary disease, participating in an 8-week pulmonary rehabilitation programme and eligible for nutritional support, were studied. Group A (n 19) received three portions of 125 ml (2380 kJ), whereas group B (n 20) received three portions of 200 ml (3350 kJ) daily. The macronutrient composition of the regimens was similar (20 % protein, 60 % carbohydrates and 20 % fat). Lung function, body weight, body composition (by bio-electrical impedance analysis), habitual dietary intake (by dietary history) and resting energy expenditure (by ventilated hood) were determined. Weight gain was compared with expected weight as predicted by a computer simulation model. Although patients in both groups significantly increased in weight, this increase was higher in group A (A, 3.3 (sd 1.9) kg; B, 2.0 (sd 1.2) kg; P=0.019), while receiving less energy. The observed weight gain in group A was similar to that expected, but in group B it was lower than expected (P<0.001). In both groups, fat-free mass and fat mass were gained in a ratio of 2:1, fat-free mass increasing primarily during the first 4 weeks. This study illustrates that there might be an optimum for the portion size of nutritional drink supplements in chronic obstructive pulmonary disease and that more is not always better.

Adipose Tissue↗