Concerns have been raised about the quality of reporting in nutritional epidemiology. Research reporting guidelines such as the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement can improve quality of reporting in observational studies. Herein, we propose recommendations for reporting nutritional epidemiology and dietary assessment research by extending the STROBE statement into Strengthening the Reporting of Observational Studies in Epidemiology—Nutritional Epidemiology (STROBE-nut). Recommendations for the reporting of nutritional epidemiology and dietary assessment research were developed following a systematic and consultative process, coordinated by a multidisciplinary group of 21 experts. Consensus on reporting guidelines was reached through a three-round Delphi consultation process with 53 external experts. In total, 24 recommendations for nutritional epidemiology were added to the STROBE checklist. When used appropriately, reporting guidelines for nutritional epidemiology can contribute to improve reporting of observational studies with a focus on diet and health.

Biodiversity is key for human and environmental health. Available dietary and ecological indicators are not designed to assess the intricate relationship between food biodiversity and diet quality. We applied biodiversity indicators to dietary intake data from and assessed associations with diet quality of women and young children. Data from 24-hour diet recalls (55% in the wet season) of n = 6,226 participants (34% women) in rural areas from seven low- and middle-income countries were analyzed. Mean adequacies of vitamin A, vitamin C, folate, calcium, iron, and zinc and diet diversity score (DDS) were used to assess diet quality. Associations of biodiversity indicators with nutrient adequacy were quantified using multilevel models, receiver operating characteristic curves, and test sensitivity and specificity. A total of 234 different species were consumed, of which <30% were consumed in more than one country. Nine species were consumed in all countries and provided, on average, 61% of total energy intake and a significant contribution of micronutrients in the wet season. Compared with Simpson’s index of diversity and functional diversity, species richness (SR) showed stronger associations and better diagnostic properties with micronutrient adequacy. For every additional species consumed, dietary nutrient adequacy increased by 0.03 (P < 0.001). Diets with higher nutrient adequacy were mostly obtained when both SR and DDS were maximal. Adding SR to the minimum cutoff for minimum diet diversity improved the ability to detect diets with higher micronutrient adequacy in women but not in children. Dietary SR is recommended as the most appropriate measure of food biodiversity in diets. Significance Current research linking biodiversity and human diets has used metrics without justification from a nutritional point of view. Diet species richness, or a count of the number of different species consumed per day, assesses both nutritional adequacy and food biodiversity of diets for women and children in rural areas. The positive association of food species richness with dietary quality was observed in both the wet and the dry season. Food biodiversity contributes to diet quality in vulnerable populations in areas with high biodiversity. Reporting the number of species consumed during dietary assessment provides a unique opportunity to cut across two critical dimensions of sustainable development—human and environmental health—and complements existing indicators for healthy and sustainable diets.

Diet-related noncommunicable diseases (NCDs) are increasing rapidly in low- and middle-income countries (LMICs) and constitute a leading cause of mortality. Although a call for global action has been resonating for years, the progress in national policy development in LMICs has not been assessed. This review of strategies to prevent NCDs in LMICs provides a benchmark against which policy response can be tracked over time. We reviewed how government policies in LMICs outline actions that address salt consumption, fat consumption, fruit and vegetable intake, or physical activity. A structured content analysis of national nutrition, NCDs, and health policies published between 1 January 2004 and 1 January 2013 by 140 LMIC members of the World Health Organization (WHO) was carried out. We assessed availability of policies in 83% (116/140) of the countries. NCD strategies were found in 47% (54/116) of LMICs reviewed, but only a minority proposed actions to promote healthier diets and physical activity. The coverage of policies that specifically targeted at least one of the risk factors reviewed was lower in Africa, Europe, the Americas, and the Eastern Mediterranean compared to the other two World Health Organization regions, South-East Asia and Western Pacific. Of the countries reviewed, only 12% (14/116) proposed a policy that addressed all four risk factors, and 25% (29/116) addressed only one of the risk factors reviewed. Strategies targeting the private sector were less frequently encountered than strategies targeting the general public or policy makers. This review indicates the disconnection between the burden of NCDs and national policy responses in LMICs. Policy makers urgently need to develop comprehensive and multi-stakeholder policies to improve dietary quality and physical activity. Please see later in the article for the Editors' Summary Noncommunicable diseases (NCDs)—chronic medical conditions including cardiovascular diseases (heart disease and stroke), diabetes, cancer, and chronic respiratory diseases (chronic obstructive pulmonary disease and asthma)—are responsible for two-thirds of the world's deaths. Nearly 80% of NCD deaths, close to 30 million per year, occur in low- and middle-income countries (LMICs), where they are also rising most rapidly. Diet and lifestyle (including smoking, lack of exercise, and harmful alcohol consumption) influence a person's risk of developing an NCD and of dying from it. Because they can be modified, these risk factors have been at the center of strategies to combat NCDs. In 2004, the World Health Organization (WHO) adopted the Global Strategy on Diet, Physical Activity and Health. For diet, it recommended that individuals achieve energy balance and a healthy weight; limit energy intake from total fats and shift fat consumption away from saturated fats to unsaturated fats and towards the elimination of trans-fatty acids; increase consumption of fruits, vegetables, legumes, whole grains, and nuts; limit the intake of free sugars; and limit salt consumption from all sources and ensure that salt is iodized. For physical activity, it recommended at least 30 minutes of regular, moderate-intensity physical activity on most days throughout a person's life. By signing onto the Global Strategy in 2004, WHO member countries agreed to implement it with high priority. A first step of implementation is usually the development of local policies. Consequently, one of the four objectives of the WHO Global Strategy is “to encourage the development, strengthening and implementation of global, regional, national and community policies and action plans to improve diets and increase physical activity.” Along the same lines, in 2011 the United Nations held a high-level meeting in which the need to accelerate the policy response to the NCD epidemic was emphasized. This study was done to assess the existing national policies on NCD prevention in LMICs. Specifically, the researchers examined how well those policies matched the WHO recommendations for intake of salt, fat, and fruits and vegetables, as well as the recommendations for physical activity. The researchers searched the Internet (including websites of relevant ministries and departments) for all publicly available national policies related to diet, nutrition, NCDs, and health from all 140 WHO member countries classified as LMICs by the World Bank in 2011. For countries for which the search did not turn up policies, the researchers sent e-mail requests to the relevant national authorities, to the regional WHO offices, and to personal contacts. All documents dated from 1 January 2004 to 1 January 2013 that included national objectives and guidelines for action regarding diet, physical exercise, NCD prevention, or a combination of the three, were analyzed in detail. Most of the policies obtained were not easy to find and access. For 24 countries, particularly in the Eastern Mediterranean, the researchers eventually gave up, unable to establish whether relevant national policies existed. Of the remaining 116 countries, 29 countries had no relevant policies, and another 30 had policies that failed to mention specifically any of the diet-related risk factors included in the analysis. Fifty-four of the 116 countries had NCD policies that addressed at least one of the risk factors. Thirty-six national policy documents contained strategies to increase fruit and vegetable intake, 20 addressed dietary fat consumption, 23 aimed to limit salt intake, and 35 had specific actions to promote physical activity. Only 14 countries, including Jamaica, the Philippines, Iran, and Mongolia, had policies that addressed all four risk factors. The policies of 27 countries mentioned only one of the four risk factors. Policies primarily targeted consumers and government agencies and failed to address the roles of the business community or civil society. Consistent with this, most were missing plans, mechanisms, and incentives to drive collaborations between the different stakeholders. More than eight years after the WHO Global Strategy was agreed upon, only a minority of the LMICs included in this analysis have comprehensive policies in place. Developing policies and making them widely accessible is a likely early step toward specific implementation and actions to prevent NCDs. These results therefore suggest that not enough emphasis is placed on NCD prevention in these countries through actions that have been proven to reduce known risk factors. That said, the more important question is what countries are actually doing to combat NCDs, something not directly addressed by this analysis. In richer countries, NCDs have for decades been the leading cause of sickness and death, and the fact that public health strategies need to emphasize NCD prevention is now widely recognized. LMICs not only have more limited resources, they also continue to carry a large burden from infectious diseases. It is therefore not surprising that shifting resources towards NCD prevention is a difficult process, even if the human cost of these diseases is massive and increasing. That only about 3% of global health aid is aimed at NCD prevention does not help the situation. The authors argue that one step toward improving the situation is better sharing of best practices and what works and what doesn't in policy development. They suggest that an open-access repository like one that exists for Europe could improve the situation. They offer to organize, host, and curate such a resource under the auspices of WHO, starting with the policies retrieved for this study, and they invite submission of additional policies and updates. Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001465.

Concerns have been raised about the quality of reporting in nutritional epidemiology. Research reporting guidelines such as the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement can improve quality of reporting in observational studies. Herein, we propose recommendations for reporting nutritional epidemiology and dietary assessment research by extending the STROBE statement into Strengthening the Reporting of Observational Studies in Epidemiology – Nutritional Epidemiology (STROBE‐nut). Recommendations for the reporting of nutritional epidemiology and dietary assessment research were developed following a systematic and consultative process, co‐ordinated by a multidisciplinary group of 21 experts. Consensus on reporting guidelines was reached through a three‐round Delphi consultation process with 53 external experts. In total, 24 recommendations for nutritional epidemiology were added to the STROBE checklist. When used appropriately, reporting guidelines for nutritional epidemiology can contribute to improve reporting of observational studies with a focus on diet and health.

In the present review, the association of out-of-home eating with anthropometric changes was examined. Peer-reviewed studies in eight databases were searched, and 15 prospective studies were included in the review. The quality of the data was assessed by considering risks of bias in sample selection, data collection methods, and the appropriateness of statistical tests. From this, seven studies, which used relatively large samples or had a follow-up period longer than 10 years, were retained for further analysis. It was concluded that eating out-of-home frequently, in the broad sense, is positively associated with the risk of becoming overweight or obese and weight change. With regard to specific out-of-home sources, the review shows that eating at fast-food outlets is associated with a greater increase in body weight and waist circumference over time than eating at restaurants and takeaway foods positively predict BMI change in women. More research is needed on out-of-home foods other than fast-foods and restaurant foods, such as street, canteen, and school foods.