Higher-diet quality is associated with higher diet costs when eating at home and away from home: National Health and Nutrition Examination Survey, 2005-2016.

OBJECTIVES: To evaluate the association between diet quality and cost for foods purchased for consumption at home and away from home. DESIGN: Cross-sectional analysis. Multivariable linear regression models evaluated the association between diet quality and cost for all food, food at home (FAH) and food away from home (FAFH). SETTING: Daily food intake data from the National Health and Nutrition Examination Survey (2005-2016). Food prices were derived using data from multiple, publicly available databases. Diet quality was assessed using the Healthy Eating Index-2015 and the Alternative Healthy Eating Index-2010. PARTICIPANTS: 30 564 individuals ≥20 years with complete and reliable dietary data. RESULTS: Mean per capita daily diet cost was $14·19 (95 % CI (13·91, 14·48)), including $6·92 (95 % CI (6·73, 7·10)) for FAH and $7·28 (95 % CI (7·05, 7·50)) for FAFH. Diet quality was higher for FAH compared to FAFH (P < 0·001). Higher diet quality was associated with higher food costs overall, FAH and FAFH (P < 0·001 for all comparisons). CONCLUSIONS: These findings demonstrate that higher diet quality is associated with higher costs for all food, FAH and FAFH. This research provides policymakers, public health professionals and clinicians with information needed to support healthy eating habits. These findings are particularly relevant to contemporary health and economic concerns that have worsened because of the COVID-19 pandemic.

Daily cost of consumer food wasted, inedible, and consumed in the United States, 2001-2016.

BACKGROUND: Consumer food waste in the United States represents substantial amounts of wasted nutrients, as well as needless environmental impact from wasted agricultural inputs, energy use, and greenhouse gas emissions. Efforts to reduce food waste at the consumer level are urgently needed to address the most prominent nutrition and environmental sustainability issues we now face. Importantly, individuals report that saving money is a salient motivator for reducing food waste, yet contemporary evidence on the consumer cost of wasted food is lacking. The objectives of this study are to 1) estimate the daily per capita cost of food wasted, inedible, and consumed 2) at home and away from home, and 3) by food group. METHODS: This study utilizes cross-sectional, nationally-representative data on food intake from the National Health and Nutrition Examination Survey (2001-2016), linked with nationally representative data on food waste from published literature, as well as data on food prices and food price inflation from multiple publicly-available sources. Survey-weighted procedures estimated daily per capita expenditure on food waste for 39,758 adults aged ≥20 y. RESULTS: Total daily per capita food expenditure was $13.27, representing 27% wasted, 14% inedible, and 59% consumed. The greatest daily food waste expenditures were observed for meat and seafood purchased for consumption outside of the home ($0.94, 95% CI: $0.90-0.99), and fruits and vegetables purchased for consumption in the home ($0.68, $0.63-0.73). CONCLUSIONS: The most cost-effective ways to reduce food waste at the consumer level are to focus waste reduction efforts on meat and seafood purchased for consumption outside of the home and fruits and vegetables purchased for consumption in the home. A number of strategies are available to help consumers reduce their food waste, which can increase their financial flexibility to purchase more healthy foods while simultaneously reducing environmental impact.

Healthy diets can create environmental trade-offs, depending on how diet quality is measured.

BACKGROUND: There is an urgent need to assess the linkages between diet patterns and environmental sustainability in order to meet global targets for reducing premature mortality and improving sustainable management of natural resources. This study fills an important research gap by evaluating the relationship between incremental differences in diet quality and multiple environmental burdens, while also accounting for the separate contributions of retail losses, inedible portions, and consumer waste. METHODS: Cross sectional, nationally-representative data on food intake in the United States were acquired from the National Health and Nutrition Examination Survey (2005-2016), and were linked with nationally-representative data on food loss and waste from published literature. Survey-weighted procedures estimated daily per capita food retail loss, food waste, inedible portions, and consumed food, and were summed to represent Total Food Demand. Diet quality was measured using the Healthy Eating Index-2015 and the Alternative Healthy Eating Index-2010. Data on food intake, loss, and waste were inputted into the US Foodprint Model to estimate the amount of agricultural land, fertilizer nutrients, pesticides, and irrigation water used to produce food. RESULTS: This study included dietary data from 50,014 individuals aged ≥2 y. Higher diet quality (HEI-2015 and AHEI-2010) was associated with greater per capita Total Food Demand, as well as greater retail loss, inedible portions, consumer waste, and consumed food (P < 0.001 for all comparisons). Consumed food accounted for 56-74% of agricultural resource use (land, fertilizer nutrients, pesticides, and irrigation water), retail loss accounted for 4-6%, inedible portions accounted for 2-15%, and consumer waste accounted for 20-23%. Higher diet quality was associated with lower use of agricultural land, but the relationship to other agricultural resources was dependent on the tool used to measure diet quality (HEI-2015 vs. AHEI-2010). CONCLUSIONS: Over one-quarter of the agricultural inputs used to produce Total Food Demand were attributable to edible food that was not consumed. Importantly, this study also demonstrates that the relationship between diet quality and environmental sustainability depends on how diet quality is measured. These findings have implications for the development of sustainable dietary guidelines, which requires balancing population-level nutritional needs with the environmental impacts of food choices.

Concurrent validity of skin carotenoid status as a concentration biomarker of vegetable and fruit intake compared to multiple 24-h recalls and plasma carotenoid concentrations across one year: a cohort study.

BACKGROUND: Biological markers of vegetable and fruit (VF) intake are needed both for nutrition surveillance and for the evaluation of nutrition interventions. Optically assessed skin carotenoid status (SCS) has been proposed as a marker of intake but there are few published validity studies to date. Therefore, the objective of the study was to examine the concurrent validity of multiple methods of assessing VF intake cross-sectionally and seasonally over one year and to discuss the relative merits and limitations of each method. METHODS: Fifty-two 40-60 y old women completed a 1-year longitudinal study that included 1) SCS assessment using resonance Raman spectroscopy (RRS) and using pressure-mediated reflection spectroscopy (RS) at 12 timepoints, 2) thirty-six 24-h recalls using the Automated Self-Administered 24-Hour Dietary Assessment Tool (ASA24; total 1866 recalls), and 3) plasma carotenoid concentrations measured every 3 months. Pearson correlation coefficients and mixed linear models were used to estimate pairwise correlations between RRS, RS, ASA24, and plasma carotenoids. RESULTS: RS and RRS were strongly correlated at baseline and over the year (r = 0.86 and 0.76; respectively, P < 0.001). RS was strongly correlated with plasma carotenoids at baseline (r = 0.70) and moderately across the year (r = 0.65), as was RRS (r = 0.77 and 0.69, respectively, all P < 0.001). At baseline, self-reported VF was weakly correlated with RRS (r = 0.33; P = 0.016), but not with RS or plasma carotenoids. Across the year, self-reported VF intake was weakly correlated with both RS (r = 0.37; P = 0.008), RRS (r = 0.37; P = 0.007), and with plasma carotenoids (r = 0.36; P < 0.008). CONCLUSIONS: SCS as measured by RS and RRS is moderately to strongly correlated with plasma carotenoid concentrations both cross-sectionally and longitudinally, indicating that it can be a powerful tool to assess carotenoid-rich VF intake in populations. CLINICAL TRIAL REGISTRY: This trial was registered at ClinicalTrials.gov as NCT01674296.

Greater vegetable variety and amount are associated with lower prevalence of coronary heart disease: National Health and Nutrition Examination Survey, 1999-2014.

BACKGROUND: The 2015-2020 Dietary Guidelines for Americans (DGA) provides specific intake recommendations for vegetable variety and amount in order to protect against chronic disease. However, to the best of our knowledge, no studies have examined the link between DGA recommended vegetable variety and cardiometabolic disease. To address this research gap, our aim was to estimate the relationship between vegetable variety, vegetable amount, and prevalent cardiometabolic disease subtypes, and to assess potential determinants of vegetable variety. METHODS: Data on food intake and reported cardiometabolic disease status were acquired for 38,981 adults from the National Health and Nutrition Examination Survey (1999-2014). Vegetable variety was measured using a modified dietary diversity index that was adjusted for the potential confounding effects of vegetable amount. Temporal trends in vegetable variety and amount were assessed using univariate linear regression models. Multivariate logistic regression models were used to estimate the relationship between vegetable variety and prevalent disease, and between vegetable amount and prevalent disease. Multivariate ordered logistic regression models were used to assess the relationship between vegetable variety and explanatory variables. RESULTS: Overall, vegetable variety decreased (P = 0.035) from 1999 to 2014, but vegetable amount did not (P = 0.864). Intake of starchy vegetables decreased (P < 0.001), and intake of dark green vegetables increased (P < 0.001) over this 16-year period, but no trends were observed for other subgroups. An inverse linear relationship was observed between vegetable variety and prevalent coronary heart disease (P-trend = 0.032) but not other prevalent diseases; and between vegetable amount and coronary heart disease (P-trend = 0.026) but not other prevalent diseases. Individuals who reported consuming dark green vegetables had lower odds of having cardiovascular disease (0.86, 95% CI: 0.74-0.99) and coronary heart disease (0.78, 0.65-0.94) compared to individuals who reported not consuming any green vegetables. Living with a domestic partner was associated with greater vegetable variety (P = < 0.001), and currently smoking was associated with lower vegetable variety (P = < 0.001). Vegetable variety and amount were positively associated (P < 0.001). CONCLUSIONS: Vegetable variety and amount were inversely associated with prevalent coronary heart disease. Vegetable variety was strongly associated with vegetable amount, likely mediated by reduced habituation and increased liking. Increasing vegetable variety and amount are still important messages for the public.

Nutrient intake disparities in the US: modeling the effect of food substitutions.

BACKGROUND: Diet quality among federal food assistance program participants remains low, and little research has assessed the diet quality of food insecure non-participants. Further research is needed to assess the extent to which food substitutions can improve the nutritional status of these vulnerable populations. Substituting egg dishes for other commonly consumed dishes at certain eating occasions may be an effective strategy for improving the daily nutrient intake among these groups. Eggs are rich in many important nutrients, and are low-cost and part of a wide range of cultural food menus, which are important considerations for low-income and ethnically diverse populations. To help guide the focus of targeted nutrition interventions and education campaigns for vulnerable populations, the present work begins by 1) estimating the prevalence of nutrient inadequacy among these groups, and then models the effect of consuming egg dishes instead of commonly consumed dishes at each eating occasion on 2) the prevalence of nutrient inadequacy, and 3) the mean intake of nutrients. METHODS: Dietary data from 34,741 adults ≥ 20 y were acquired from the National Health and Nutrition Examination Survey, 2001-2014. Diet pattern modeling was used to substitute commonly consumed egg dishes for commonly consumed main dishes at breakfast, lunch, and dinner. National Cancer Institute usual intake methods were used to estimate the prevalence of inadequate intake of 31 nutrients pre- and post-substitution, and a novel index was used to estimate change in intake of all nutrients collectively. RESULTS: Substituting eggs for commonly consumed main dishes at lunch or dinner did not change total daily nutrient intake for each group (P > 0.05), but decreased the prevalence of vitamin D inadequacy by 1-4 percentage points (P < 0.01). Substituting eggs for commonly consumed foods at breakfast increased the prevalence of folate inadequacy by 8-12 percentage points among each group (P < 0.01). CONCLUSIONS: When making food substitutions to increase nutrient intake, eating occasion should be an important consideration. Further research is needed to better understand how food substitutions affect diet costs, which may be an important driver of food purchasing decisions among low income individuals with limited food budgets.

Reducing US cardiovascular disease burden and disparities through national and targeted dietary policies: A modelling study.

BACKGROUND: Large socio-economic disparities exist in US dietary habits and cardiovascular disease (CVD) mortality. While economic incentives have demonstrated success in improving dietary choices, the quantitative impact of different dietary policies on CVD disparities is not well established. We aimed to quantify and compare the potential effects on total CVD mortality and disparities of specific dietary policies to increase fruit and vegetable (F&V) consumption and reduce sugar-sweetened beverage (SSB) consumption in the US. METHODS AND FINDINGS: Using the US IMPACT Food Policy Model and probabilistic sensitivity analyses, we estimated and compared the reductions in CVD mortality and socio-economic disparities in the US population potentially achievable from 2015 to 2030 with specific dietary policy scenarios: (a) a national mass media campaign (MMC) aimed to increase consumption of F&Vs and reduce consumption of SSBs, (b) a national fiscal policy to tax SSBs to increase prices by 10%, (c) a national fiscal policy to subsidise F&Vs to reduce prices by 10%, and (d) a targeted policy to subsidise F&Vs to reduce prices by 30% among Supplemental Nutrition Assistance Program (SNAP) participants only. We also evaluated a combined policy approach, combining all of the above policies. Data sources included the Surveillance, Epidemiology, and End Results Program, National Vital Statistics System, National Health and Nutrition Examination Survey, and published meta-analyses. Among the individual policy scenarios, a national 10% F&V subsidy was projected to be most beneficial, potentially resulting in approximately 150,500 (95% uncertainty interval [UI] 141,400-158,500) CVD deaths prevented or postponed (DPPs) by 2030 in the US. This far exceeds the approximately 35,100 (95% UI 31,700-37,500) DPPs potentially attributable to a 30% F&V subsidy targeting SNAP participants, the approximately 25,800 (95% UI 24,300-28,500) DPPs for a 1-y MMC, or the approximately 31,000 (95% UI 26,800-35,300) DPPs for a 10% SSB tax. Neither the MMC nor the individual national economic policies would significantly reduce CVD socio-economic disparities. However, the SNAP-targeted intervention might potentially reduce CVD disparities between SNAP participants and SNAP-ineligible individuals, by approximately 8% (10 DPPs per 100,000 population). The combined policy approach might save more lives than any single policy studied (approximately 230,000 DPPs by 2030) while also significantly reducing disparities, by approximately 6% (7 DPPs per 100,000 population). Limitations include our effect estimates in the model; these estimates use interventional and prospective observational studies (not exclusively randomised controlled trials). They are thus imperfect and should be interpreted as the best available evidence. Another key limitation is that we considered only CVD outcomes; the policies we explored would undoubtedly have additional beneficial effects upon other diseases. Further, we did not model or compare the cost-effectiveness of each proposed policy. CONCLUSIONS: Fiscal strategies targeting diet might substantially reduce CVD burdens. A national 10% F&V subsidy would save by far the most lives, while a 30% F&V subsidy targeting SNAP participants would most reduce socio-economic disparities. A combined policy would have the greatest overall impact on both mortality and socio-economic disparities.

Cardiometabolic Mortality by Supplemental Nutrition Assistance Program Participation and Eligibility in the United States.

OBJECTIVES: To investigate total and cause-specific cardiometabolic mortality among Supplemental Nutrition Assistance Program (SNAP) participants, SNAP-eligible nonparticipants, and SNAP-ineligible individuals overall and by age, gender, race/ethnicity, and other characteristics. METHODS: We performed a prospective study with nationally representative survey data from the National Health Interview Survey (2000-2009), merged with subsequent Public-Use Linked Mortality Files (2000-2011). We used survey-weighted Cox proportional hazards models adjusted for age and gender to estimate hazard ratios of total and cause-specific cardiometabolic mortality for 499 741 US adults aged 25 years or older. RESULTS: Over a mean of 6.8 years of follow-up (maximum 11.9 years), 39 293 deaths occurred, including 7408 heart disease, 2185 stroke, and 1376 diabetes deaths. Individuals participating in SNAP exhibited higher total and cardiovascular disease mortality, largely limited to non-Hispanic Whites and non-Hispanic Blacks, than both SNAP-eligible nonparticipants and SNAP-ineligible individuals, and higher diabetes mortality across races/ethnicities (P < .01). CONCLUSIONS: Participants in SNAP require greater focus to understand and further address their poor health outcomes. Public Health Implications. Low-income Americans require even greater efforts to improve their health than they currently receive, and such efforts should be a priority for public health policymakers.

Diet quality on meatless days: National Health and Nutrition Examination Survey (NHANES), 2007-2012.

OBJECTIVE: To compare diet quality scores between adult non-meat eaters and meat eaters, and to compare the consumption of diet components across quintiles of diet quality. DESIGN: Cross-sectional analysis. The Healthy Eating Index-2010 (HEI-2010) and Alternative Healthy Eating Index-2010 (AHEI-2010) were used to assess mean diet quality. Differences in consumption of diet components between quintiles of diet quality were tested using post hoc Wald tests and z tests. SETTING: The National Health and Nutrition Examination Survey (NHANES), 2007-2012. SUBJECTS: The sample consisted of 16810 respondents aged≥18 years, including 280 individuals who reported not consuming meat, poultry, game birds or seafood on two non-consecutive days of dietary recall. Dietary data were obtained from one dietary recall per individual. RESULTS: Non-meat eaters had substantially greater HEI-2010 and AHEI-2010 scores than meat eaters (P<0·05). Among non-meat eaters, mean consumption across HEI-2010 quintiles demonstrated different (P<0·05) amounts of empty calories and unsaturated:saturated fatty acids. Mean consumption across AHEI-2010 quintiles demonstrated different (P<0·05) amounts of nuts and legumes, vegetables and PUFA. CONCLUSIONS: Public health messages targeted at vegetarians and others who may choose to eat meat-free on certain days should emphasize decreased consumption of empty calories, and increased consumption of nuts and legumes, PUFA and vegetables, as a way to improve overall dietary quality.

Characterizing trends in fruit and vegetable intake in the USA by self-report and by supply-and-disappearance data: 2001-2014.

OBJECTIVE: To examine the comparability of fruit and vegetable (F&V) intake data in the USA from 2001 to 2014 between data acquired from two national data collection programmes. DESIGN: Cross-sectional analysis. Linear regression models estimated trends in daily per capita intake of total F&V. Pooled differences in intake of individual F&V (n 109) were examined by processing form (fresh, frozen, canned, dried and juice). SETTING: What We Eat in America (WWEIA, 2001-2014) and Loss-Adjusted Food Availability data series (LAFA, 2001-2014). RESULTS: No temporal trends were observed in daily per capita intake of total F&V from 2001 to 2014 using WWEIA and LAFA. Modest differences between WWEIA and LAFA were observed in mean pooled intake of most individual F&V. CONCLUSIONS: WWEIA and LAFA produced similar estimates of F&V intake. However, WWEIA may be best suited for monitoring intake at the national level because it allows for the identification of individual F&V in foods with multiple ingredients, and it is structured for sub-population analysis and covariate control. LAFA does retain advantages for other research protocols, specifically by providing the only nationally representative estimates of food losses at various points in the food system, which makes it useful for examining the adequacy of the food supply at the agricultural, retail and consumer levels.

Inter- and independent effects of region and race/ethnicity on variety of fruit and vegetable consumption in the USA: 2011 Behavioral Risk Factor Surveillance System (BRFSS).

OBJECTIVE: (i) To estimate the independent and combined effects of race/ethnicity and region on the variety of fruits and vegetables consumed in the USA in 2011; and (ii) to assess whether and to what extent race/ethnicity and region may synergistically influence variety of fruit and vegetable consumption. DESIGN: Cross-sectional analysis. Multivariate logistic regression predicted the likelihood of meeting fruit and vegetable variety indicators independently and in combination for each race/ethnicity and region. Interaction effects models were used to test for interaction effects between race/ethnicity and region on fruit and vegetable variety. SETTING: The 2011 Behavioral Risk Factor Surveillance System (BRFSS). SUBJECTS: The sample consisted of 275 864 adult respondents. RESULTS: Fewer than half of respondents consumed fruit and all vegetable subcategories at least once weekly. The adjusted likelihood of meeting fruit and vegetable variety indicators varied significantly by race/ethnicity and region (P<0·05). Significant interactions between race/ethnicity and region were found for at least once weekly consumption of beans, orange vegetables, all vegetables, and fruit and all vegetables (P<0·05). CONCLUSIONS: Our results reinforce previous findings that the variety of vegetable consumption is lacking and is particularly evident among some population subgroups, such as non-Hispanic blacks in the Midwest USA, who may benefit from targeted dietary interventions.

Pulse crops: nutrient density, affordability, and environmental impact.

Introduction: Sustainable foods need to be nutrient-rich, affordable, environmentally friendly, and socially acceptable. Pulses, which include beans, lentils, chickpeas, and dried peas are a food group that can fit all those criteria. Methods: These concepts were tested serially using nutrient profiling methods that focused on protein and were extended to include food prices, greenhouse gas emissions, and energy demand. The present sustainability analyses were based on the US Department of Agriculture (USDA) nutrient composition and food prices data. Environmental impact data came from life cycle assessments (LCA). First, the USDA Protein Foods Group was disaggregated into animal and plant proteins. Plant proteins were separated into pulses, soy products, and nuts and seeds. Results: Pulses were among the lowest-cost protein sources (per 100 g and per 100 kcal) and had the lowest greenhouse gas emissions GHGE and energy demand. Pulses were among the most sustainable foods when monetary and energy costs were expressed per 50 g of protein (equivalent to 100% DV). Pulses scored well on the Nutrient Rich Food (NRF9.3) nutrient profiling system and on the related Affordable Nutrition Index that assessed nutrient density per penny. Discussion: Pulses are a source of low-cost plant-based protein and a variety of priority vitamins and minerals, have low carbon footprint and energy demand, and are a valued culinary ingredient across diverse regions and cultures. As dietary guidance turns to plant-based diets, pulses need to be integrated into the global sustainability framework.

Augmenting the National Nutrition Data System to Promote Diet Sustainability Analyses.

Research on sustainable diets has become an important and growing area of the nutrition field, but recent studies have pointed to a lack of sustainability metrics and methods that are hindering research and policy progress. To fill this gap, the White House National Strategy on Hunger, Nutrition, and Health calls for increased funding to improve metrics, data collection, and research to address all domains of sustainability, which include nutrition/health, economic, environmental, and social domains. Commodity recipe databases, such as the Food Commodity Intake Database (FCID), are important tools for conducting diet sustainability analyses because they translate mixed dishes from dietary surveys, such as the National Health and Nutrition Examination Survey (NHANES), into commodity ingredients. These ingredients have been linked to data on environmental impacts and economic costs from other databases, thus facilitating collaboration between nutrition researchers, environmental scientists, economists, and others. These linkages cannot be made with other components of the national nutrition data system, such as the Food Patterns Equivalents Database (FPED), because the disaggregated food groups from them are not relevant for examining environmental impacts. Although the NHANES is conducted on an ongoing basis, and FPED is continually updated, the FCID has not been officially updated since 2010. This severely limits advancements in sustainability research and related policy analyses. In this commentary, we argue that the federal government should promote this diet sustainability work by integrating a commodity recipe database into the national nutrition data system, and updating it on a regular basis, as it does with other component databases.

Opportunities for Consistent and Holistic Metrics to Support Food Systems Transformation: A Summary of a Symposium Presented at Nutrition 2023.

There is an urgent need for global food systems transformation to realize a future where planetary health reaches its full potential. Paramount to this vision is the ability of stakeholders across sectors to understand how foods and dietary patterns impact food systems inclusive of all domains of sustainability-environmental, nutrition/health, economic and social. This article is a synopsis of presentations by 3 food systems experts to share the latest science in a session entitled "How do you measure sustainability? Opportunities for consistent and holistic metrics to support food systems transformation" at the American Society for Nutrition's 2023 annual conference. As summarized here, global population data showing widespread malnutrition underscore the important role of dietary diversity through a balance of plant- and animal-source foods to achieve nutritionally adequate diets and reduce risk of noncommunicable diseases. Yet, recent international audits of countries, companies, and organizations and their sustainability targets largely demonstrate an underrepresentation of robust nutrition/health metrics to support public nutrition and health progress. Addressing limitations in diet-sustainability modeling systems provides a viable opportunity to accurately reflect the important contributions and trade-offs of diets across all domains of sustainability to ultimately support evidence-based decision making in advancing healthy food systems.

Restricted carbohydrate diets below 45% energy are not associated with risk of mortality in the National Health and Nutrition Examination Survey, 1999-2018.

Introduction: Cardiometabolic diseases (CMD) are the leading causes of death for people living in the United States. Dietary strategies, such as restricting carbohydrate intake, are becoming popular strategies for improving health status. However, there is limited and often contradictory evidence on whether restricting carbohydrate intake is related to all-cause, CMD, or cardiovascular disease (CVD) mortality. Methods: The objective of the present study was to evaluate the association between restricted carbohydrate diets (<45%en) and mortality from all-causes, CMD, and CVD, stratified by fat amount and class. Data were acquired using the National Health and Nutrition Examination Survey (1999-2018) linked with mortality follow-up until December 31, 2019 from the Public-use Linked Mortality Files. Multivariable survey-weighted Cox proportional hazards models estimated hazard ratios for 7,958 adults (≥20 y) that consumed <45%en from carbohydrates and 27,930 adults that consumed 45-65%en from carbohydrates. Results: During the study period a total of 3,780 deaths occurred, including 1,048 from CMD and 1,007 from CVD, during a mean follow-up of 10.2 y. Compared to individuals that met carbohydrate recommendations (45-65%en), those that consumed carbohydrate restricted diets (<45%en) did not have significantly altered risk of mortality from all-causes (HR: 0.98; 95% CI: 0.87, 1.11), CMD (1.18; 0.95, 1.46), or CVD (1.20; 0.96, 1.49). These findings were maintained when the restricted carbohydrate diet group was stratified by intake of total fat, saturated fat (SFA), monounsaturated fat (MUFA), and polyunsaturated fat (PUFA). Discussion: Carbohydrate restriction (<45%en) was not associated with mortality from all-causes, CVD, or CMD. Greater efforts are needed to characterize the risk of mortality associated with varied degrees of carbohydrate restriction, e.g., low (<26%en) and high (>65%en) carbohydrate diets separately.

Are People Consuming the Diets They Say They Are? Self-Reported vs Estimated Adherence to Low-Carbohydrate and Low-Fat Diets: National Health and Nutrition Examination Survey, 2007-2018.

BACKGROUND: Mischaracterization of dietary intake by patients and study participants is a common problem that presents challenges to clinical and public health approaches to improve diet quality, identify healthy eating patterns, and reduce the risk of chronic disease. OBJECTIVE: This study examined participants' self-reported adherence to low-carbohydrate and low-fat diets compared with their estimated adherence using up to 2 24-hour recalls. DESIGN: This cross-sectional study acquired data on dietary intake from respondents in the National Health and Nutrition Examination Survey, 2007-2018. PARTICIPANTS/SETTING: This study included 30 219 respondents aged 20 years and older who had complete and reliable dietary data and were not pregnant or breastfeeding. MAIN OUTCOME MEASURES: The main outcome was prevalence of self-reported and estimated adherence to low-carbohydrate or low-fat diet patterns. STATISTICAL ANALYSES PERFORMED: Self-reported adherence to low-carbohydrate or low-fat diets was evaluated using responses to questionnaires. Estimated adherence to these diets was assessed using data from up to 2 24-hour recalls and usual intake methodology developed by the National Cancer Institute. RESULTS: Of the 1.4% of participants who reported following a low-carbohydrate diet, estimated adherence (<26% energy from carbohydrates) using 24-hour recalls was 4.1%, whereas estimated adherence among those that did not report following a low-carbohydrate diet was <1% (P value for difference = .014). Of the 2.0% of participants who reported following a low-fat diet, estimated adherence (<30% energy from fat) was 23.0%, whereas estimated adherence among those who did not report following a low-fat diet was 17.8% (P value for difference = .048). CONCLUSIONS: This research demonstrates that most individuals mischaracterized their diet pattern when compared with up to 2 24-hour recalls. These findings emphasize the need for clinicians and public health professionals to be cautious when interpreting individuals' self-reported diet patterns, and should aim to collect more detailed dietary data when possible.

Foodprint 2.0: A computational simulation model that estimates the agricultural resource requirements of diet patterns.

Reducing the environmental pressures stemming from food production is central to meeting global sustainability targets. Shifting diets represents one lever for improving food system sustainability, and identifying sustainable diet opportunities requires computational models to represent complex systems and allow users to evaluate counterfactual scenarios. Despite an increase in the number of food system sustainability models, there remains a lack of transparency of data inputs and mathematical formulas to facilitate replication by researchers and application by diverse stakeholders. Further, many models lack the ability to model multiple geographic scales. The present study introduces Foodprint 2.0, which fills both gaps. Foodprint 2.0 is an updated biophysical simulation model that estimates the agricultural resource requirements of diet patterns and can be adapted to suit a variety of research purposes. The objectives of this study are to: 1) describe the new features of Foodprint 2.0, and 2) demonstrate model performance by estimating the agricultural resource requirements of food demand in the United States (US) using nationally representative dietary data from the National Health and Nutrition Examination Survey from 2009-2018. New features of the model include embedded functions to integrate individual-level dietary data that allow for variance estimation; new data and calculations to account for the resource requirements of food trade and farmed aquatic food; updated user interface; expanded output data for over 200 foods that include the use of fertilizer nutrients, pesticides, and irrigation water; supplementary files that include input data for all parameters on an annual basis from 1999-2018; sample programming code; and step-by-step instructions for users. This study demonstrates that animal-sourced foods consumed in the US accounted for the greatest share of total land use, fertilizer nutrient use, pesticide use, and irrigation water use, followed by grains, fruits, and vegetables. Greater adherence to the Dietary Guidelines for Americans was associated with lower use of land and fertilizer nutrients, and greater use of pesticides and irrigation water. Foodprint 2.0 is a highly modifiable model that can be a useful resource for informing sustainable diet policy discussions.

Greater adherence to the Dietary Guidelines for Americans is associated with lower diet-related greenhouse gas emissions but higher costs.

Introduction: Few studies have evaluated the sustainability of popular diet patterns in the US, which limits policy action and impedes consumer efficacy to make sustainable dietary changes. This study filled this gap by evaluating the relationship between diet quality, greenhouse gas emissions (GHGE), and diet cost for plant-based, restricted carbohydrate, low grain, low fat, and time restricted diet patterns. Methods: Dietary data were retrieved from the National Health and Nutrition Examination Survey (2011-2018, n = 8,146) and linked with data on GHGE and food prices from publicly available databases. Diet quality was measured using the Healthy Eating Index-2015. The present study (1) compared the mean diet quality, GHGE, and diet cost between diet patterns, (2) evaluated the association of diet quality to GHGE and diet cost for each diet pattern, and (3) estimated the contribution of food sources to GHGE and diet cost for each diet pattern. Results: Higher diet quality was associated with lower GHGE for the general population and for most diet patterns (p < 0.01) except for the plant-based and time restricted diet patterns (p > 0.05). Higher diet quality was associated with higher cost for the general population and for all dietary patterns (p < 0.01) except the time restricted diet pattern (p > 0.05). Protein foods, mostly beef, accounted for the largest share of GHGE (29-40%) and diet cost (28-47%) for all diet patterns except plant-based. Discussion: Higher diet quality was associated with lower GHGE but was often accompanied by higher diet cost. These sustainability trade-offs can help inform major policy discussions in the US and shed light on further research needs in the area of food systems transformation.

Fat Intake Modifies the Association between Restricted Carbohydrate Diets and Prevalent Cardiometabolic Diseases among Adults in the United States: National Health and Nutrition Examination Survey, 1999-2018.

Background: Cardiometabolic diseases (CMDs), which include heart disease, stroke, and diabetes, account for over one-third of the mortality burden in the United States annually. Nearly one-half of all deaths from CMD are attributable to suboptimal diet quality, and many Americans are turning to special diets for general health improvement. Among the most popular of these diets restrict daily carbohydrate intake to <45% of energy, yet their association with CMD is not well understood. Objectives: This study evaluated the association between restricted carbohydrate diets and prevalent CMD, stratified by fat intake. Methods: Dietary and CMD data were retrieved from 19,078 participants aged ≥20 y in the National Health and Nutrition Examination Survey, 1999-2018. The National Cancer Institute methodology was used to assess usual dietary intake. Results: Compared to participants that met recommendations for all macronutrients, those that consumed restricted carbohydrate diets were 1.15 (95% CI: 1.14, 1.16) times as likely to have CMD; and those that met recommendations for carbohydrates, but not all macronutrients, were 1.02 (95% CI: 1.02, 1.03) times as likely to have CMD. Higher intakes of saturated and polyunsaturated fat were associated with greater prevalence of CMD in restricted and recommended carbohydrate intake groups. Higher intake of monounsaturated fat was associated with lower prevalence of CMD among participants that met carbohydrate, but not all macronutrient, recommendations. Conclusions: To our knowledge, this is the first nationally representative study to evaluate the relationship between carbohydrate restriction and CMD, stratifying by fat intake. Greater efforts are needed to understand longitudinal relationships between carbohydrate restriction and CMD.

Greenhouse gas emissions, cost, and diet quality of specific diet patterns in the United States.

BACKGROUND: Major policy agendas are calling for accelerated investment in research that addresses the impact of diet patterns on multiple domains of sustainability. OBJECTIVES: To evaluate the comparative greenhouse gas emissions, diet cost, and diet quality of plant-based, low-grain, restricted carbohydrate, low-fat, and time-restricted diet patterns on a daily per capita basis. METHODS: Dietary data from the National Health and Nutrition Examination Survey (2013-2016, n = 4025) were merged with data on greenhouse gas emissions (GHGEs) and food prices from multiple databases. The Healthy Eating Index-2015 was used to measure diet quality. RESULTS: The plant-based diet pattern had the lowest GHGEs [3.5 kg carbon dioxide equivalent (CO2eq); 95% confidence interval (CI): 3.3, 3.8 kg CO2eq] and among the lowest diet cost ($11.51; 95% CI: $10.67, $12.41), but diet quality (45.8; 95% CI: 43.3, 48.5) was similar (P > 0.005) to most other diet patterns. All of the sustainability impacts of the low-grain diet pattern were intermediate. The restricted carbohydrate diet pattern had the highest diet cost ($18.46; 95% CI: $17.80, $19.13) but intermediate diet quality (46.8; 95% CI: 45.7, 47.9) and moderate-to-high GHGEs (5.7 kg CO2eq; 95% CI: 5.4, 5.9 kg CO2eq). The low-fat diet pattern had the highest diet quality (52.0; 95% CI: 50.8, 53.1) and intermediate GHGEs (4.4 kg CO2eq; 95% CI: 4.1, 4.6 kg CO2eq) and diet cost ($14.53; 95% CI: $13.73, $15.38). The time-restricted diet pattern had among the lowest diet quality score (42.6; 95% CI: 40.8, 44.6), had GHGEs similar to most other diet patterns (4.6 kg CO2eq; 95% CI: 4.2, 5.0 kg CO2eq), and low-to-moderate diet cost ($12.34; 95% CI: $11.38, $13.40). CONCLUSIONS: Most diet patterns are associated with sustainability trade-offs. The nature of these trade-offs can help inform discussions on food and nutrition policy in the United States, including the National Strategy on Hunger, Nutrition, and Health, and future Dietary Guidelines for Americans.