School food environment policies may be a critical tool to promote healthy diets in children, yet their effectiveness remains unclear.
To systematically review and quantify the impact of school food ...environment policies on dietary habits, adiposity, and metabolic risk in children.
We systematically searched online databases for randomized or quasi-experimental interventions assessing effects of school food environment policies on children's dietary habits, adiposity, or metabolic risk factors. Data were extracted independently and in duplicate, and pooled using inverse-variance random-effects meta-analysis. Habitual (within+outside school) dietary intakes were the primary outcome. Heterogeneity was explored using meta-regression and subgroup analysis. Funnel plots, Begg's and Egger's test evaluated potential publication bias.
From 6,636 abstracts, 91 interventions (55 in US/Canada, 36 in Europe/New Zealand) were included, on direct provision of healthful foods/beverages (N = 39 studies), competitive food/beverage standards (N = 29), and school meal standards (N = 39) (some interventions assessed multiple policies). Direct provision policies, which largely targeted fruits and vegetables, increased consumption of fruits by 0.27 servings/d (n = 15 estimates (95%CI: 0.17, 0.36)) and combined fruits and vegetables by 0.28 servings/d (n = 16 (0.17, 0.40)); with a slight impact on vegetables (n = 11; 0.04 (0.01, 0.08)), and no effects on total calories (n = 6; -56 kcal/d (-174, 62)). In interventions targeting water, habitual intake was unchanged (n = 3; 0.33 glasses/d (-0.27, 0.93)). Competitive food/beverage standards reduced sugar-sweetened beverage intake by 0.18 servings/d (n = 3 (-0.31, -0.05)); and unhealthy snacks by 0.17 servings/d (n = 2 (-0.22, -0.13)), without effects on total calories (n = 5; -79 kcal/d (-179, 21)). School meal standards (mainly lunch) increased fruit intake (n = 2; 0.76 servings/d (0.37, 1.16)) and reduced total fat (-1.49%energy; n = 6 (-2.42, -0.57)), saturated fat (n = 4; -0.93%energy (-1.15, -0.70)) and sodium (n = 4; -170 mg/d (-242, -98)); but not total calories (n = 8; -38 kcal/d (-137, 62)). In 17 studies evaluating adiposity, significant decreases were generally not identified; few studies assessed metabolic factors (blood lipids/glucose/pressure), with mixed findings. Significant sources of heterogeneity or publication bias were not identified.
Specific school food environment policies can improve targeted dietary behaviors; effects on adiposity and metabolic risk require further investigation. These findings inform ongoing policy discussions and debates on best practices to improve childhood dietary habits and health.
While food pricing is a promising strategy to improve diet, the prospective impact of food pricing on diet has not been systematically quantified.
To quantify the prospective effect of changes in ...food prices on dietary consumption.
We systematically searched online databases for interventional or prospective observational studies of price change and diet; we also searched for studies evaluating adiposity as a secondary outcome. Studies were excluded if price data were collected before 1990. Data were extracted independently and in duplicate. Findings were pooled using DerSimonian-Laird's random effects model. Pre-specified sources of heterogeneity were analyzed using meta-regression; and potential for publication bias, by funnel plots, Begg's and Egger's tests.
From 3,163 identified abstracts, 23 interventional studies and 7 prospective cohorts with 37 intervention arms met inclusion criteria. In pooled analyses, a 10% decrease in price (i.e., subsidy) increased consumption of healthful foods by 12% (95%CI = 10-15%; N = 22 studies/intervention arms) whereas a 10% increase price (i.e. tax) decreased consumption of unhealthful foods by 6% (95%CI = 4-8%; N = 15). By food group, subsidies increased intake of fruits and vegetables by 14% (95%CI = 11-17%; N = 9); and other healthful foods, by 16% (95%CI = 10-23%; N = 10); without significant effects on more healthful beverages (-3%; 95%CI = -16-11%; N = 3). Each 10% price increase reduced sugar-sweetened beverage intake by 7% (95%CI = 3-10%; N = 5); fast foods, by 3% (95%CI = 1-5%; N = 3); and other unhealthful foods, by 9% (95%CI = 6-12%; N = 3). Changes in price of fruits and vegetables reduced body mass index (-0.04 kg/m2 per 10% price decrease, 95%CI = -0.08-0 kg/m2; N = 4); price changes for sugar-sweetened beverages or fast foods did not significantly alter body mass index, based on 4 studies. Meta-regression identified direction of price change (tax vs. subsidy), number of intervention components, intervention duration, and study quality score as significant sources of heterogeneity (P-heterogeneity<0.05 each). Evidence for publication bias was not observed.
These prospective results, largely from interventional studies, support efficacy of subsidies to increase consumption of healthful foods; and taxation to reduce intake of unhealthful beverages and foods. Use of subsidies and combined multicomponent interventions appear most effective.
Dietary habits are major contributors to coronary heart disease, stroke, and diabetes. However, comprehensive evaluation of etiologic effects of dietary factors on cardiometabolic outcomes, their ...quantitative effects, and corresponding optimal intakes are not well-established.
To systematically review the evidence for effects of dietary factors on cardiometabolic diseases, including comprehensively assess evidence for causality; estimate magnitudes of etiologic effects; evaluate heterogeneity and potential for bias in these etiologic effects; and determine optimal population intake levels.
We utilized Bradford-Hill criteria to assess probable or convincing evidence for causal effects of multiple diet-cardiometabolic disease relationships. Etiologic effects were quantified from published or de novo meta-analyses of prospective studies or randomized clinical trials, incorporating standardized units, dose-response estimates, and heterogeneity by age and other characteristics. Potential for bias was assessed in validity analyses. Optimal intakes were determined by levels associated with lowest disease risk.
We identified 10 foods and 7 nutrients with evidence for causal cardiometabolic effects, including protective effects of fruits, vegetables, beans/legumes, nuts/seeds, whole grains, fish, yogurt, fiber, seafood omega-3s, polyunsaturated fats, and potassium; and harms of unprocessed red meats, processed meats, sugar-sweetened beverages, glycemic load, trans-fats, and sodium. Proportional etiologic effects declined with age, but did not generally vary by sex. Established optimal population intakes were generally consistent with observed national intakes and major dietary guidelines. In validity analyses, the identified effects of individual dietary components were similar to quantified effects of dietary patterns on cardiovascular risk factors and hard endpoints.
These novel findings provide a comprehensive summary of causal evidence, quantitative etiologic effects, heterogeneity, and optimal intakes of major dietary factors for cardiometabolic diseases, informing disease impact estimation and policy planning and priorities.
IMPORTANCE: In the United States, national associations of individual dietary factors with specific cardiometabolic diseases are not well established. OBJECTIVE: To estimate associations of intake of ...10 specific dietary factors with mortality due to heart disease, stroke, and type 2 diabetes (cardiometabolic mortality) among US adults. DESIGN, SETTING, AND PARTICIPANTS: A comparative risk assessment model incorporated data and corresponding uncertainty on population demographics and dietary habits from National Health and Nutrition Examination Surveys (1999-2002: n = 8104; 2009-2012: n = 8516); estimated associations of diet and disease from meta-analyses of prospective studies and clinical trials with validity analyses to assess potential bias; and estimated disease-specific national mortality from the National Center for Health Statistics. EXPOSURES: Consumption of 10 foods/nutrients associated with cardiometabolic diseases: fruits, vegetables, nuts/seeds, whole grains, unprocessed red meats, processed meats, sugar-sweetened beverages (SSBs), polyunsaturated fats, seafood omega-3 fats, and sodium. MAIN OUTCOMES AND MEASURES: Estimated absolute and percentage mortality due to heart disease, stroke, and type 2 diabetes in 2012. Disease-specific and demographic-specific (age, sex, race, and education) mortality and trends between 2002 and 2012 were also evaluated. RESULTS: In 2012, 702 308 cardiometabolic deaths occurred in US adults, including 506 100 from heart disease (371 266 coronary heart disease, 35 019 hypertensive heart disease, and 99 815 other cardiovascular disease), 128 294 from stroke (16 125 ischemic, 32 591 hemorrhagic, and 79 578 other), and 67 914 from type 2 diabetes. Of these, an estimated 318 656 (95% uncertainty interval UI, 306 064-329 755; 45.4%) cardiometabolic deaths per year were associated with suboptimal intakes—48.6% (95% UI, 46.2%-50.9%) of cardiometabolic deaths in men and 41.8% (95% UI, 39.3%-44.2%) in women; 64.2% (95% UI, 60.6%-67.9%) at younger ages (25-34 years) and 35.7% (95% UI, 33.1%-38.1%) at older ages (≥75 years); 53.1% (95% UI, 51.6%-54.8%) among blacks, 50.0% (95% UI, 48.2%-51.8%) among Hispanics, and 42.8% (95% UI, 40.9%-44.5%) among whites; and 46.8% (95% UI, 44.9%-48.7%) among lower-, 45.7% (95% UI, 44.2%-47.4%) among medium-, and 39.1% (95% UI, 37.2%-41.2%) among higher-educated individuals. The largest numbers of estimated diet-related cardiometabolic deaths were related to high sodium (66 508 deaths in 2012; 9.5% of all cardiometabolic deaths), low nuts/seeds (59 374; 8.5%), high processed meats (57 766; 8.2%), low seafood omega-3 fats (54 626; 7.8%), low vegetables (53 410; 7.6%), low fruits (52 547; 7.5%), and high SSBs (51 694; 7.4%). Between 2002 and 2012, population-adjusted US cardiometabolic deaths per year decreased by 26.5%. The greatest decline was associated with insufficient polyunsaturated fats (−20.8% relative change 95% UI, −18.5% to −22.8%), nuts/seeds (−18.0% 95% UI, −14.6% to −21.0%), and excess SSBs (−14.5% 95% UI, −12.0% to −16.9%). The greatest increase was associated with unprocessed red meats (+14.4% 95% UI, 9.1%-19.5%). CONCLUSIONS AND RELEVANCE: Dietary factors were estimated to be associated with a substantial proportion of deaths from heart disease, stroke, and type 2 diabetes. These results should help identify priorities, guide public health planning, and inform strategies to alter dietary habits and improve health.
In many developing countries, nutritional and epidemiological transitions are contributing to continuous undernutrition and escalating overnutrition, resulting in coexisting forms of malnutrition ...often referred as the "double burden of malnutrition" (DBM). This complex phenomenon constitutes an unprecedented challenge to global public health and has been prioritized by international health organizations, prompting governments to swift action. Specifically, five years ago the World Health Organization proposed a roadmap to tackle the DBM though so-called "double-duty actions". The objective of this review was to synthesize the literature on interventions which address the DBM.
We developed a scoping review to identify interventions addressing the DBM. We searched PUBMED for papers reporting interventions until December 2019. Articles examining interventions, government policies, or tools at the individual, household, or community level to address the double burden of malnutrition were included.
Seven articles met the inclusion criteria. Three were from sub-Saharan Africa, one was from Southeast Asia, and one was from Central America. Two were modelling studies, with one covering 24 low-income countries and the other focusing on Ghana.
Notwithstanding the pressing issue of the DBM, there is a paucity of studies examining double-duty actions despite the attention that it has garnered within the global nutrition community. Whilst nutrient deficiencies may be curbed by poverty reduction measures, for obesity prevention nutrition, education and promotion of physical activity, along with the encouragement of local food production, may be instrumental.
IMPORTANCE: Most studies of US dietary trends have evaluated major macronutrients or only a few dietary factors. Understanding trends in summary measures of diet quality for multiple individual foods ...and nutrients, and the corresponding disparities among population subgroups, is crucial to identify challenges and opportunities to improve dietary intake for all US adults. OBJECTIVE: To characterize trends in overall diet quality and multiple dietary components related to major diseases among US adults, including by age, sex, race/ethnicity, education, and income. DESIGN, SETTING, AND PARTICIPANTS: Repeated cross-sectional investigation using 24-hour dietary recalls in nationally representative samples including 33 932 noninstitutionalized US adults aged 20 years or older from 7 National Health and Nutrition Examination Survey (NHANES) cycles (1999-2012). The sample size per cycle ranged from 4237 to 5762. EXPOSURES: Calendar year and population sociodemographic subgroups. MAIN OUTCOMES AND MEASURES: Survey-weighted, energy-adjusted mean consumption and proportion meeting targets of the American Heart Association (AHA) 2020 continuous diet scores, AHA score components (primary: total fruits and vegetables, whole grains, fish and shellfish, sugar-sweetened beverages, and sodium; secondary: nuts, seeds, and legumes, processed meat, and saturated fat), and other individual food groups and nutrients. RESULTS: Several overall dietary improvements were identified (P < .01 for trend for each). The AHA primary diet score (maximum of 50 points) improved from 19.0 to 21.2 (an improvement of 11.6%). The AHA secondary diet score (maximum of 80 points) improved from 35.1 to 38.5 (an improvement of 9.7%). Changes were attributable to increased consumption between 1999-2000 and 2011-2012 of whole grains (0.43 servings/d; 95% CI, 0.34-0.53 servings/d) and nuts or seeds (0.25 servings/d; 95% CI, 0.18-0.34 servings/d) (fish and shellfish intake also increased slightly) and to decreased consumption of sugar-sweetened beverages (0.49 servings/d; 95% CI, 0.28-0.70 servings/d). No significant trend was observed for other score components, including total fruits and vegetables, processed meat, saturated fat, or sodium. The estimated percentage of US adults with poor diets (defined as <40% adherence to the primary AHA diet score components) declined from 55.9% to 45.6%, whereas the percentage with intermediate diets (defined as 40% to 79.9% adherence to the primary AHA diet score components) increased from 43.5% to 52.9%. Other dietary trends included increased consumption of whole fruit (0.15 servings/d; 95% CI, 0.05-0.26 servings/d) and decreased consumption of 100% fruit juice (0.11 servings/d; 95% CI, 0.04-0.18 servings/d). Disparities in diet quality were observed by race/ethnicity, education, and income level; for example, the estimated percentage of non-Hispanic white adults with a poor diet significantly declined (53.9% to 42.8%), whereas similar improvements were not observed for non-Hispanic black or Mexican American adults. There was little evidence of reductions in these disparities and some evidence of worsening by income level. CONCLUSIONS AND RELEVANCE: In nationally representative US surveys conducted between 1999 and 2012, several improvements in self-reported dietary habits were identified, with additional findings suggesting persistent or worsening disparities based on race/ethnicity, education level, and income level. These findings may inform discussions on emerging successes, areas for greater attention, and corresponding opportunities to improve the diets of individuals living in the United States.
Nutrition transition towards a Western diet is happening in parallel with the rapidly increasing rates of cardiovascular disease and its risk factors in Kuwait. The cardiometabolic deaths ...attributable to poor diet have not been quantified among Kuwaiti adults.
Using a Comparative Risk Assessment model that incorporated dietary intake data from Kuwait's first national nutrition survey, number of cardiometabolic deaths from the World Health Organization, and estimated associations of diet with cardiometabolic deaths from the Global Burden of Disease project, we estimated the number and proportion of cardiometabolic deaths attributable to suboptimal intake of 10 dietary factors among Kuwaiti adults ages 25+ years, and by population subgroups.
An estimated 1,308 (95% uncertainty interval UI = 1,228-1,485) cardiometabolic deaths were attributed to suboptimal diet, accounting for 64.7% (95% UI = 60.7%-73.4%) of all cardiometabolic deaths in Kuwait in 2009. The low intake of nuts/seeds was associated with the highest estimated number and proportion of cardiometabolic deaths (n = 380, 18.8%), followed by high intake of sodium (n = 256, 12.6%), low intake of fruits (n = 250, 12.4%), low intake of vegetables (n = 236, 11.7%), low intake of whole grains (n = 201, 9.9%), and high intake of sugar-sweetened beverages (n = 201, 9.9%). The estimated proportions of cardiometabolic deaths attributable to suboptimal diet were higher in men (67.7%) than women (57.8%) and in younger adults aged 25-34 years (84.5%) than older adults aged ≥55 years (55.6%).
Suboptimal dietary intake was associated with a very substantial proportion of cardiometabolic deaths among Kuwaiti adults in 2009, with young adults and men experiencing the largest proportion of diet-associated cardiometabolic deaths in Kuwait.
Nutritional data reduction methods are widely applied in nutrition epidemiology in order to classify individuals into meaningful groups with similar dietary patterns. To date, none of the existing ...studies have applied latent class analysis to examine dietary patterns which include meal types consumed throughout a day. We investigated main meal patterns followed on weekend and weekdays, and evaluated their associations with cardio-metabolic biomarkers. The analyses were performed within the NANS (National Adult Nutrition Survey) a cross-sectional national food consumption survey of 1500 nationally representative Irish adults. A total number of seven dietary patterns were identified using latent class analysis. The typical meal pattern followed by the majority of the population was characterized by consumption of cereal or toast for breakfast, skipping or consuming a sandwich for light meal, and meat or fish with potatoes, pasta or vegetables for the main meal. Eating patterns differed on weekends, and those participants who consumed meat and eggs for breakfast instead of breakfast cereal and skipped light meal were more likely to have an unhealthier dietary pattern, a higher diastolic blood pressure, and increased serum ferritin. The application of data reduction techniques to simplify the multifaceted nature of dietary data is a useful approach to derive patterns, which might shed further light on the typical dietary patterns followed by populations.
Although reasonable to assume, it is not yet clear whether malnourished countries are at higher risk for severe or fatal coronavirus disease 2019 (COVID-19). This study aims to identify the countries ...where prevalent malnutrition may be a driving factor for fatal disease after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.
Using estimates from the Global Burden of Disease 2019, country-level burden of malnutrition was quantified using four indicators: death rates for child growth failure (underweight, stunting, and/or wasting) and years lived with disability (YLD) attributed to iron and vitamin A deficiencies and high body mass index (BMI). Global mortality descriptors of the ongoing COVID-19 pandemic were extracted from the European Centre for Disease Prevention and Control, and case fatality ratios (CFRs) were calculated introducing a lag time of 10 weeks after the first death of a confirmed case. Bivariate analyses for 172 countries were carried out for malnutrition indicators and fatal COVID-19. Correlations between burden indicators were characterized by Spearman's rank correlation coefficients (ρ) and visually by scatterplots. Restricted cubic splines and underlying negative binomial regressions adjusted for countries' age-structure, prevalent chronic comorbidities related to COVID-19, population density, and income group were used to explore non-linear relationships.
Stratified by the World Bank income group, a moderate positive association between YLD rates for iron deficiency and CFRs for COVID-19 was observed for low-income countries (ρ = 0.60,
= 0.027), whereas no clear indications for the association with child growth failure, vitamin A deficiency, or high BMI were found (ρ < 0.30). Countries ranking high on at least three malnutrition indicators and presenting also an elevated CFR for COVID-19 are sub-Saharan African countries, namely, Angola, Burkina Faso, Chad, Liberia, Mali, Niger, Sudan, and Tanzania, as well as Yemen and Guyana.
Population-level malnutrition appears to be related to increased rates of fatal COVID-19 in areas with an elevated burden of undernutrition, such as countries in the Sahel strip. COVID-19 response plans in malnourished countries, vulnerable to fatal COVID-19, should incorporate food security, nutrition, and social protection as a priority component in order to reduce COVID-19 fatality.
Breast cancer (BC) is a significant health concern among European women, with the highest prevalence rates among all cancers. Existing BC prediction models account for major risks such as hereditary, ...hormonal and reproductive factors, but research suggests that adherence to a healthy lifestyle can reduce the risk of developing BC to some extent. Understanding the influence and predictive role of lifestyle variables in current risk prediction models could help identify actionable, modifiable, targets among high-risk population groups.
To systematically review population-based BC risk prediction models applicable to European populations and identify lifestyle predictors and their corresponding parameter values for a better understanding of their relative contribution to the prediction of incident BC.
A systematic review was conducted in PubMed, Embase and Web of Science from January 2000 to August 2021. Risk prediction models were included if (i) developed and/or validated in adult cancer-free women in Europe, (ii) based on easily ascertained information, and (iii) reported models' final predictors. To investigate further the comparability of lifestyle predictors across models, estimates were standardised into risk ratios and visualised using forest plots.
From a total of 49 studies, 33 models were developed and 22 different existing models, mostly from Gail (22 studies) and Tyrer-Cuzick and co-workers (12 studies) were validated or modified for European populations. Family history of BC was the most frequently included predictor (31 models), while body mass index (BMI) and alcohol consumption (26 and 21 models, respectively) were the lifestyle predictors most often included, followed by smoking and physical activity (7 and 6 models respectively). Overall, for lifestyle predictors, their modest predictive contribution was greater for riskier lifestyle levels, though highly variable model estimates across different models.
Given the increasing BC incidence rates in Europe, risk models utilising readily available risk factors could greatly aid in widening the population coverage of screening efforts, while the addition of lifestyle factors could help improving model performance and serve as intervention targets of prevention programmes.