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S M Krebs-Smith

Publications and source records attributed to S M Krebs-Smith.

At least 19 recordsLinked to original sources
PubMed2001

Evaluating the impact of population changes in diet, physical activity, and weight status on population risk for colon cancer (United States).

OBJECTIVE: To estimate the effects of observed population-level changes in risk factors on population risk and incidence of disease. METHODS: Trends in a set of risk factors for colon cancer (vegetable intake, red meat intake, alcohol consumption, physical activity levels, and weight status) were modeled for the US adult population over the years 1975-1995 and combined with relative risk estimates from epidemiologic studies and a probability distribution for the induction period to estimate the percentage change in incidence rates from 1985 to 1995 due to the five risk factors. A sensitivity analysis was performed to account for imprecision related to estimates of trends in behavior and epidemiologic risk. RESULTS: Increased vegetable intake and decreased intakes of red meat and alcohol reduced risk, while reduced physical activity and increased body mass index increased risk for colon cancer. When all five factors were considered together, change in the average population relative risk was small and the risk factors accounted for little of the recently observed decline in incidence. CONCLUSIONS: Although these factors have the potential to greatly affect risk of colon cancer and incidence rates, little of that potential was realized since adverse trends neutralized what progress had been made in the areas of vegetables, red meat, and alcohol consumption.

Adult↗
PubMed2001

Let the pyramid guide your food choices: capturing the total diet concept.

This paper discusses how the guideline "Eat a variety of foods" became "Let the Pyramid guide your food choices," presents background information on the food guidance system upon which the Food Guide Pyramid is based and reviews methods that have been used to assess aspects of the total diet, i.e., the variety, moderation and proportionality, promoted by this guidance. The methods include measures of dietary variety, patterns based on Pyramid food group intakes and scoring methods comprised of multiple dietary components. Highlights of results from these methods include the following. Although approximately one third of the U.S. population eat at least some food from all Pyramid food groups, only approximately 1-3% eat the recommended number of servings from all food groups on a given day. Fruits are the most commonly omitted food group. Vegetables and meat are the groups most commonly met by adults, and dairy the most commonly met by youth. Intakes of specific types of vegetables (i.e., dark green, deep yellow) and of grains (i.e., whole grains) are well below that recommended; intakes of total fat and added sugars exceed current recommendations. Scoring methods show those diets of the majority of the population require improvement, and that diets improve with increases in education and income. This paper also discusses the limitations and strengths of these approaches, and concludes with suggestions to improve current food guidance and methods to assess the total diet.

Age Factors↗
PubMed2001

Choose a variety of fruits and vegetables daily: understanding the complexities.

The 2000 edition of Nutrition and Your Health: Dietary Guidelines for Americans is the first to include a recommendation aimed specifically at fruits and vegetables, apart from grains. This paper discusses these changes in the Dietary Guidelines, summarizes the methods of assessment pertaining to fruit and vegetable intakes and their related factors, and reviews the data available on current levels and trends over time. Recent methodological advances in the measurement of both the aggregate U.S. food supply and foods consumed by individuals have allowed for better estimates with which recommendations can be compared. The data on individual intakes suggest the following: Americans are consuming fruits and vegetables at a level near the minimum recommendations; to be in concordance with energy-based recommendations, they would have to consume approximately 2 more servings per day; and dark green and deep yellow vegetables are accounting for a disproportionately small share of the total. Fruit and vegetable consumption appears to be rising, but only slightly, and this increase might be only an artifact of shifts in the population demographics. A number of studies suggest that low income households in poor central cities and sparsely populated rural areas often have less access to food stores and face higher prices for food, including fruits and vegetables, compared with other households. At the aggregate level, supplying enough fruits and vegetables to meet dietary recommendations for all U.S. consumers would require adjustments in U.S. agricultural production, trade, marketing practices and prices of these commodities.

Age Factors↗
PubMed2001

Choose beverages and foods to moderate your intake of sugars: measurement requires quantification.

The Dietary Guidelines for Americans, which form the basis of federal nutrition policy, have changed in subtle, but important ways with regard to sugars since they were first introduced in 1980; one might say they have become "sweeter" over time. Nonetheless, they have continued to maintain that there is a concern with overconsumption of sugars in the diets of Americans. Although the Dietary Guidelines themselves have never quantified how much constitutes overconsumption vs. moderation, the Food Guide Pyramid provides some guidance on that subject. The Pyramid's recommendations for added sugars, which vary by total energy level, are posed as a benchmark for gauging the appropriateness of the population's intakes. Data from the Food Supply series and from the Continuing Surveys of Food Intakes by Individuals are used to assess recent intakes. The population is consuming added sugars at levels far in excess of recommendations; this is generally true for all population subgroups examined, but especially for adolescents. Soft drinks are the major source of added sugars in the diet. Suggestions are given to facilitate correction of these dietary imbalances.

Age Factors↗
PubMed2000

Low energy reporters vs others: a comparison of reported food intakes.

OBJECTIVE: To partition the food reports of low energy reporters (LERs) and non-LERs into four aspects-tendency to report a given food, frequency of reports per user, portion sizes per mention, and the qualitative (low-fat, low-sugar, low-energy) differences of the reports-in order to determine what differentiates them from one another. ASSESSMENT METHOD: Two non-consecutive 24h dietary recalls. Low energy reporting was defined as energy intake lower than 80% of estimated basal metabolic rate. SETTING: In-home personal interviews. SUBJECTS: 8334 adults from a stratified, multi-stage area probability sample designed to be representative of noninstitutionlized persons residing in households in the United States. RESULTS: Across all different types of foods, there are those food groups which LERs are less likely to report (28 of 44 food groups), those which they report less frequently when they do report them (15 of 44 groups), and those for which they report smaller quantities per mention (26 of 44). Qualitative differences in the food choices-that is, differences in fat, sugar, and/or energy content-were not so widespread (4 of 24 food groups). CONCLUSIONS: The practical application of analyses such as these is to improve the methods of gathering dietary data so that this kind of bias can be reduced. Further methodological research is needed to reduce the likelihood of respondents neglecting to mention foods and underestimating portion sizes.

Adult↗
PubMed2000

Evaluation of 2 brief instruments and a food-frequency questionnaire to estimate daily number of servings of fruit and vegetables.

BACKGROUND: Measurement of fruit and vegetable intake is important in the surveillance of populations and in epidemiologic studies that examine the relations between diet and disease. Some situations require the use of brief dietary assessment tools. OBJECTIVE: Our objective was to evaluate the performance of 2 brief dietary assessment instruments, a 7-item standard screener and a new 16-item screener, and a complete food-frequency questionnaire (FFQ) in measuring total fruit and vegetable consumption. DESIGN: About 800 men and women from the National Institutes of Health-AARP Diet and Health Study completed an FFQ, 1 of the 2 screeners, and two 24-h dietary recalls. Fruit and vegetable intakes as measured by each screener and the FFQ were compared with estimated true usual intake by using a measurement-error model. RESULTS: Median daily servings of fruit and vegetables were underestimated by both screeners. The estimated agreement between true intake and the screener was higher for the new screener than for the standard screener and was higher for women than for men. The estimated agreement between true intake and the FFQ was higher than that for both screeners. Attenuation coefficients for the FFQ and screeners were comparable. CONCLUSIONS: For estimating median intakes of fruit and vegetables and the prevalence of recommended intakes being met, the use of screeners without appropriate adjustment is suboptimal. For estimating relative risks in the relations between fruit and vegetable intake and disease, screeners and this FFQ are similar in performance.

Aged↗
PubMed1998

Progress in improving diet to reduce cancer risk.

BACKGROUND: In an effort to decrease cancer risk among the population, national health objectives for the year 2000 included recommendations to decrease intake of dietary fat and alcohol and increase intake of fruits, vegetables, and grains. The purpose of this article is to assess trends in the intake of these dietary components relative to the national health objectives. METHODS: National food supply data and food consumption survey data were reviewed for their appropriateness for monitoring intake trends. Recent data from both sources are described and interpreted. RESULTS: Americans have made modest but important improvements in their diets in recent years and may meet the "Healthy People 2000" dietary objectives aimed at decreasing cancer risk. Intake of fruits, vegetables, and grains are higher, and those of fat and alcohol are lower than they were at the beginning of the decade. These trends are consistent with recent improvements in mortality rates for those cancer sites with the strongest associations with diet: the colon/rectum, prostate, and breast. CONCLUSIONS: Although the average intake of fruits, vegetables, and grain products is higher, it should be noted that the objective represents the minimum recommendations. Within each of these major food groups, further improvements can be made. In addition, special efforts should be made to guide children toward improvements in their diets and to monitor the diets of children and other subgroups.

Alcoholic Beverages↗
PubMed1998

Dietary sources of nutrients among US adults, 1989 to 1991.

OBJECTIVE: To identify major food sources of 27 nutrients and dietary constituents for US adults. DESIGN: Single 24-hour dietary recalls were used to assess intakes. From 3,970 individual foods reported, 112 groups were created on the basis of similarities in nutrient content or use. Food mixtures were disaggregated using the US Department of Agriculture (USDA) food grouping system. SUBJECTS/SETTING: A nationally representative sample of adults aged 19 years or older (n = 10,638) from USDA's 1989-91 Continuing Survey of Food Intakes by Individuals. ANALYSES PERFORMED: For each of 27 dietary components, the contribution of each food group to intake was obtained by summing the amount provided by the food group for all respondents and dividing by total intake from all food groups for all respondents. RESULTS: This article updates previous work and is, to the authors' knowledge the first to provide such data for carotenes, vitamin B-12, magnesium, and copper. Beef, yeast bread, poultry, cheese, and milk were among the top 10 sources of energy, fat, and protein. The following other major sources also contributed more than 2% to energy intakes: carbohydrate: yeast bread, soft drinks/soda, cakes/cookies/ quick breads/doughnuts, sugars/syrups/jams, potatoes (white), ready-to-eat cereal, and pasta; protein: pasta; and fat: margarine, salad dressings/mayonnaise, and cakes/ cookies/quick breads/doughnuts. Ready-to-eat cereals, primarily because of fortification, were among the top 10 food sources for 18 of 27 nutrients. APPLICATIONS/CONCLUSIONS: These analyses are the most current regarding food sources of nutrients and, because of disaggregation of mixtures, provide a truer picture of contributions of each food group.

Adult↗
PubMed1998

Dietary sources of nutrients among US children, 1989-1991.

OBJECTIVE: To identify major food sources of nutrients and dietary constituents for US children. METHODS: Twenty-four-hour dietary recalls were collected from a nationally representative sample of children age 2 to 18 years (n = 4008) from the US Department of Agriculture's 1989-1991 Continuing Survey of Food Intakes by Individuals. For each of 16 dietary constituents, the contribution of each of 113 food groups was obtained by summing the amount provided by the food group for all individuals and dividing by total intake from all food groups for all individuals. RESULTS: Milk, yeast bread, cakes/cookies/quick breads/donuts, beef, and cheese are among the top 10 sources of energy, fat, and protein. Many of the top 10 sources of carbohydrate (yeast bread, soft drinks/sodas, milk, ready-to-eat cereal, cakes/cookies/quick breads/donuts, sugars/syrups/jams, fruit drinks, pasta, white potatoes); protein (poultry, ready-to-eat cereal, pasta); and fat (potato chips/corn chips/popcorn) also contributed >2% each to energy intakes. Ready-to-eat cereal is among the top contributors to folate, vitamin A, vitamin C, iron, and zinc intakes. Fruit drinks, containing little juice, contribute approximately 14% of total vitamin C intakes. CONCLUSIONS: Fortified foods are influential contributors to many vitamins and minerals. Low nutrient-dense foods are major contributors to energy, fats, and carbohydrate. This compromises intakes of more nutritious foods and may impede compliance with current dietary guidance.

Adolescent↗
PubMed1997

Method for assessing food intakes in terms of servings based on food guidance.

We describe a method for comparing food intakes reported in surveys with recommendations given in the US Department of Agriculture's food guide pyramid. Such comparison was previously difficult because many foods are eaten as mixtures that cannot be categorized into pyramid food groups and because food intake data and food recommendations are expressed in different units of measurement. We developed a recipe file showing ingredients at multiple levels of breakdown and used it to disaggregate food mixtures into their ingredients so that they could be placed into pyramid food groups. Food-specific weight consistent with the pyramid definitions for serving sizes were derived from the food code book of the 1989-1991 Continuing Survey of Food Intakes by Individuals and used to develop a serving-weight file. Data collected from 8181 adults aged > or = 20 y in the survey were used to estimate the mean number of servings from pyramid food groups and percentages of the population meeting pyramid recommendations. The mean numbers of servings were close to the minimum recommendations for the grain, vegetable, and meat groups and well below the minimum recommendations for the fruit and dairy groups. large proportions of adults (43-72%) failed to meet the dietary recommendations. Our method has several nutrition monitoring and nutrition education applications.

Adult↗
PubMed1997

Characterizing food intake patterns of American adults.

Food-pattern analysis provides a way to examine diets in a multidimensional context. This study examined the diets of 8181 adults in the 1989-1991 Continuing Survey of Food Intakes by Individuals and evaluated whether they met the federal recommendations for each of five food groups. The sample was partitioned among 32 different food-intake patterns, six of which represented 44% of the population. Nutrient profiles associated with each of the patterns indicated that failure to meet one or more of the food-group recommendations was associated with nutrient inadequacy, macronutrient imbalance, or both. A reexamination of the data to account for low energy reporters did not alter these findings. The pattern of meeting all five of the food-group recommendations was among the least common, accounting for only 1% of adults' intakes.

Adult↗
PubMed1997

Food intakes of US children and adolescents compared with recommendations.

OBJECTIVES: To determine the proportion of youth meeting national recommendations for food group intake and to identify food intake patterns. DESIGN: The US Department of Agriculture's 1989-1991 Continuing Surveys of Food Intakes by Individuals were used to estimate food intake. Intake was determined from 3 days of diet by disaggregating foods into their component ingredients and using weights that correspond to servings. PARTICIPANTS: The sample included 3307 youth, 2 to 19 years of age, living in the 48 conterminous United States. Main Outcome Measures. Mean number of servings and percentage of individuals meeting national recommendations for food group intake according to demographic characteristics, patterns of intake, and nutrient profiles associated with each pattern. RESULTS: Mean numbers of servings per day were below minimum recommendations for all food groups except the dairy group (ages 2 to 11). Percentages of youth meeting recommendations ranged from approximately 30% for fruit, grain, meat, and dairy to 36% for vegetables. Sixteen percent of youth did not meet any recommendations, and 1% met all recommendations. The pattern of meeting all recommendations resulted in nutrient intakes above the recommended dietary allowances and was high in fat. Conversely, meeting none of the recommendations resulted in intakes well below the recommended dietary allowances for some nutrients. Total fat and added sugars averaged 35% and 15% of energy, respectively, and levels were similar among most demographic groups. CONCLUSION: Children and teens in the United States follow eating patterns that do not meet national recommendations. Nutrition education and intervention are needed among US children.

Adolescent↗
PubMed1996

Fruit and vegetable intakes of children and adolescents in the United States.

OBJECTIVES: To identify the ways in which fruits and vegetables are consumed by children, to provide estimates of their intakes compared with recommendations, and to estimate the percentage of children meeting those recommendations. DESIGN: We examined 3 days of dietary data from respondents in the US Department of Agriculture's 1989-1991 Continuing Survey of Food Intakes by Individuals. All foods reported in the survey were disaggregated into their component ingredients; all fruit and vegetable ingredients were assigned specific weights to correspond with a serving as defined by current dietary guidance materials; and the number of servings of each fruit and vegetable was tallied. PARTICIPANTS: A total of 3148 children and adolescents aged 2 to 18 years in the 48 conterminous United States. MAIN OUTCOME MEASURES: Percentages of fruit and vegetable servings consumed in various forms, mean number of servings consumed per day, and percentage of persons meeting various recommendations by sex/age, race/ethnicity, and household income. RESULTS: Nearly one quarter of all vegetables consumed by children and adolescents were french fries. Their intakes of all fruits and of dark green and/or deep yellow vegetables were very low compared with recommendations. Only one in five children consumed five or more servings of fruits and vegetables per day. CONCLUSION: Pediatricians should encourage the consumption of fruits and vegetables, especially dark green and deep yellow vegetables, by children.

Adolescent↗
PubMed1996

Contribution of dieting to the inverse association between energy intake and body mass index.

OBJECTIVE: To examine the association of energy and % energy from fat with body mass index (BMI) and determine if self-reported dieting altered observed associations. DESIGN: Dietary intake data based on dietary recalls from four nonconsecutive days over a 1 year period were examined relative to BMI. The relation between energy intake and % energy from fat and BMI was examined by linear regression analysis. SUBJECTS: The sample included 1854 free-living women aged 19-50 years who participated in the 1985-6 Continuing Surveys of Food Intakes by Individuals conducted by the United States Department of Agriculture. RESULTS: Reported energy intake was inversely associated with BMI (regression coefficient (beta) = -0.001 24, standard error (s.e.) = 0.000 31). Controlling for low energy dieting alone reduced the inverse energy intake-BMI association by approximately 20% (beta = -0.001 00, s.e. = 0.000 31), compared to reductions of 16%, 13% and 10%, respectively, when health status, age and education were added individually to the energy intake-BMI linear regression. Physical activity, smoking status, % energy from fat and report of low fat dieting did not reduce the energy intake-BMI association. Controlling for nondietary factors related to BMI and potentially influencing energy intake reduced the inverse energy intake-BMI association by approximately 22% (beta = -0.000 97, s.e. = 0.00025). Further adjustment for low energy dieting on day 1 reduced the inverse energy intake-BMI association by 40% (beta = -0.000 74, s.e. = 0.000 26), suggesting that intermittent energy restriction was a significant factor in the reduced energy intake reported among overweight women. Percent energy from fat was not associated with BMI (beta = 0.049, s.e. = 0.025, P = 0.055). Exclusion of 37 women reporting poor health status further attenuated the inverse association between energy intake and BMI (beta = -0.000 64), s.e. = 0.000 26), while it strengthened the previously non-significant positive association between % energy from fat and BMI (beta = 0.062; s.e. = 0.024). CONCLUSION: Intermittent energy restriction appeared to be a significant factor in the reduced energy intake reported among overweight women in this sample. Adequate assessment of energy expenditure is required to correctly interpret the association of energy intake to body weight.

Adult↗
PubMed1995

US adults' fruit and vegetable intakes, 1989 to 1991: a revised baseline for the Healthy People 2000 objective.

OBJECTIVES: This study provides revised baseline data for the Healthy People 2000 objective related to fruit and vegetable intakes, accounting for fruits and vegetable intakes, accounting for fruits and vegetables from all sources and measuring servings in a manner consistent with current dietary guidance. METHODS: Dietary data from 8181 adults in the US Department of Agriculture's 1989-1991 Continuing Surveys of Food Intakes by Individuals were examined. All foods were disaggregated into their component ingredients; all fruit and vegetable ingredients were assigned specific weights to correspond to a serving as defined by current dietary guidance materials; and the number of servings was tallied. RESULTS: While mean intakes of fruits and vegetables--4.3 servings per day--were not far from the Year 2000 objective, only 32% of American adults' intakes met the objective. When more stringent standards were set either to compensate for higher calorie levels or to achieve the balance between fruits and vegetables suggested in current guidance, only 24% and 12%, respectively, met the recommendations. CONCLUSIONS: These results suggest a need to develop strategies for overcoming barriers to eating fruits and vegetables.

Adult↗
PubMed1994

"Eat for Health": a supermarket intervention for nutrition and cancer risk reduction.

OBJECTIVES: The results of an evaluation of "Eat for Health," a supermarket nutrition intervention, are presented. The study tested whether such a program could be successfully carried out and whether it could effect changes in knowledge, attitudes, and food purchasing behavior in line with nutrition and cancer risk reduction guidelines. METHODS: The evaluation consisted of an in-store monitoring element, an in-store and telephone consumer survey, and an analysis of sales data on selected foods. A matched-pair design, using a total of 40 stores in the intervention and comparison groups, was used. RESULTS: The intervention was successfully implemented and had limited success in changing some food purchasing behaviors. There appeared to be no effect on knowledge and attitudes except for increased awareness of a link between diet and cancer and of the program itself. CONCLUSIONS: Despite the intervention's success, limitations of the consumer survey and sales data analyses and the continuing diffusion of nutrition messages throughout society make it difficult to specify the impact of this program on consumer nutrition knowledge and behaviors.

Adult↗