Toward a science-based classification of processed foods to support meaningful research and effective health policies.

Processed foods have been part of the American diet for decades, with key roles in providing a safe, available, affordable, and nutritious food supply. The USDA Food Guides beginning in 1916 and the US Dietary Guidelines for Americans (DGA) since 1980 have included various types of commonly consumed processed foods (e.g., heated, fermented, dried) as part of their recommendations. However, there are multiple classification systems based on "level" of food processing, and additional evidence is needed to establish the specific properties of foods classified as "highly" or "ultra"-processed (HPF/UPFs). Importantly, many foods are captured under HPF/UPF definitions, ranging from ready-to-eat fortified whole grain breakfast cereals to sugar-sweetened beverages and baked goods. The consequences of implementing dietary guidance to limit all intake of foods currently classified as HPF/UPF may require additional scrutiny to evaluate the impact on consumers' ability to meet daily nutrient recommendations and to access affordable food, and ultimately, on health outcomes. Based on a meeting held by the Institute for the Advancement of Food and Nutrition Sciences in May 2023, this paper provides perspectives on the broad array of foods classified as HPF/UPFs based on processing and formulation, including contributions to nutrient intake and dietary patterns, food acceptability, and cost. Characteristics of foods classified as UPF/HPFs are considered, including the roles and safety approval of food additives and the effect of food processing on the food matrix. Finally, this paper identifies information gaps and research needs to better understand how the processing of food affects nutrition and health outcomes.

Perspective: Challenges and Strategies to Reduce the Sodium Content of Foods by the Food Service Industry.

Most Americans have dietary sodium intakes that exceed the recommended limits, which is a risk factor for hypertension and CVD. The share of total food expenditures for foods prepared and consumed away from home (FAFH) is ∼55%. These foods are consumed at various venues, including restaurants, workplaces, schools and universities, military installations, and assisted living/long-term care facilities. The food service industry has dealt with and continues to deal with various challenges in its attempt to reduce the sodium content in the foods that they prepare and sell. Despite these challenges, there have been various successful strategies used to reduce the sodium content in FAFH. This perspective article provides an overview of the challenges and strategies that have been used by the food service industry to reduce sodium in FAFH, as well as future sodium reduction strategies. Because of the widespread consumption of FAFH, implementing such future strategies could have a profound impact on the sodium content of the American diet.

Challenges in the design, interpretation, and reporting of randomized controlled clinical studies on the health effects of whole foods.

Given the challenges with nutrition research, the Canadian Nutrition Society and Intertek Health Sciences Inc held an expert consultation in late 2019 to discuss the development and implementation of best practices for clinical trials on whole foods. Key challenges in the design, interpretation, and reporting of clinical efficacy studies on whole foods and opportunities for the future development of best practices are reported. Novelty: Outlines existing tools, resources, and checklists for clinical nutrition trials and provides clear and tangible steps to develop best practices for studies on whole foods.

Global evaluation of the use of glycaemic impact measurements to food or nutrient intake.

OBJECTIVE: Measures of glycaemic impact (e.g. postprandial glucose (PPG), oral glucose tolerance test (OGTT) and glycaemic index (GI)) are used by government health and regulatory agencies and public health associations around the world. The objective of this global review was to identify similarities and differences in the use of glycaemic impact measures for potential considerations for harmonisation. DESIGN: A literature and internet search was conducted to identify country government agencies and health associations that provide guidance or recommendations for PPG, OGTT, GI and glycaemic load. RESULTS: Based on this global review, the use of GI for food labelling (e.g. low GI) is limited and its use is voluntary. The application of OGTT as a diagnostic measurement of diabetes and gestational diabetes is widely used and in a consistent manner among the different regions of the world. Time-specific (e.g. 2 h) PPG is commonly used as a target not to exceed in individuals with diabetes and gestational diabetes. PPG is used by regulatory agencies for the substantiation of food labelling. There are differences, however, among regulatory agencies in the specific measure of PPG (i.e. PPG AUC v. peak PPG). Maximum targets for 2-h PPG for individuals with diabetes and gestational diabetes, ranging between 6 and 10 mmol/l, across countries suggest a potential consideration to harmonise PPG targets. CONCLUSIONS: There is general consistency in the use and/or target levels of glycaemic impact measures; however, there is a potential need to investigate harmonisation strategies on certain aspects of glycaemic impact measures.

Perspective: Measuring Sweetness in Foods, Beverages, and Diets: Toward Understanding the Role of Sweetness in Health.

Various global public health agencies recommend minimizing exposure to sweet-tasting foods or beverages. The underlying rationale is that reducing exposure to the perception of sweet tastes, without regard to the source of sweetness, may reduce preferences for sweetness, added sugar intake, caloric intake, and body weight. However, the veracity of this sequence of outcomes has yet to be documented, as revealed by findings from recent systematic reviews on the topic. Efforts to examine and document the effects of sweetness exposure are needed to support evidence-based recommendations. They require a generally agreed-upon methodology for measuring sweetness in foods, beverages, and the overall diet. Although well-established sensory evaluation techniques exist for individual foods in laboratory settings, they are expensive and time-consuming, and agreement on the optimal approach for measuring the sweetness of the total diet is lacking. If such a measure could be developed, it would permit researchers to combine data from different studies and populations and facilitate the design and conduct of new studies to address unresolved research questions about dietary sweetness. This narrative review includes an overview of available sensory techniques, their strengths and limitations, recent efforts to measure the sweetness of foods and diets across countries and cultures, and a proposed future direction for improving methods for measuring sweetness toward developing the data required to support evidence-based recommendations around dietary sweetness.

Guidance for the Conduct and Reporting of Clinical Trials of Breast Milk Substitutes.

Importance: Breast milk substitutes (BMS) are important nutritional products evaluated in clinical trials. Concerns have been raised about the risk of bias in BMS trials, the reliability of claims that arise from such trials, and the potential for BMS trials to undermine breastfeeding in trial participants. Existing clinical trial guidance does not fully address issues specific to BMS trials. Objectives: To establish new methodological criteria to guide the design, conduct, analysis, and reporting of BMS trials and to support clinical trialists designing and undertaking BMS trials, editors and peer reviewers assessing trial reports for publication, and regulators evaluating the safety, nutritional adequacy, and efficacy of BMS products. Design, Setting, and Participants: A modified Delphi method was conducted, involving 3 rounds of anonymous questionnaires and a face-to-face consensus meeting between January 1 and October 24, 2018. Participants were 23 experts in BMS trials, BMS regulation, trial methods, breastfeeding support, infant feeding research, and medical publishing, and were affiliated with institutions across Europe, North America, and Australasia. Guidance development was supported by an industry consultation, analysis of methodological issues in a sample of published BMS trials, and consultations with BMS trial participants and a research ethics committee. Results: An initial 73 criteria, derived from the literature, were sent to the experts. The final consensus guidance contains 54 essential criteria and 4 recommended criteria. An 18-point checklist summarizes the criteria that are specific to BMS trials. Key themes emphasized in the guidance are research integrity and transparency of reporting, supporting breastfeeding in trial participants, accurate description of trial interventions, and use of valid and meaningful outcome measures. Conclusions and Relevance: Implementation of this guidance should enhance the quality and validity of BMS trials, protect BMS trial participants, and better inform the infant nutrition community about BMS products.

Review of the scientific evidence used for establishing US policies on added sugars.

The 2015 Dietary Guidelines for Americans Advisory Committee has set recommendations to limit added sugars. This action was based on the association between dietary pattern quality scores and chronic disease risk, the results of meta-analyses conducted for the World Health Organization, and data from modeling of dietary patterns for establishing the US Department of Agriculture's Healthy US-Style Eating Patterns. Recommendations provided by the 2015-2020 Dietary Guidelines for Americans were used by the US Food and Drug Administration to establish, for the first time, the mandatory declaration of added sugars and a Daily Value of added sugars for the Nutrition Facts label. This review provides an overview of the scientific evidence considered by the World Health Organization, the 2015-2020 Dietary Guidelines for Americans, and the US Food and Drug Administration for setting recent polices and regulations on added sugars and highlights important issues and inconsistencies in the evaluations and interpretations of the evidence.

Qualified health claim for whole-grain intake and risk of type 2 diabetes: an evidence-based review by the US Food and Drug Administration.

The objective of this review is to explain how the US Food and Drug Administration (FDA) used its evidence-based review system to evaluate the scientific evidence for a qualified health claim on the role of whole-grain consumption in reducing the risk of type 2 diabetes. The labeling of health claims, including qualified health claims, on conventional foods and dietary supplements requires premarket approval by the FDA. Health claims characterize the relationship between a substance (food or food component) and a disease (eg, diabetes or cardiovascular disease) or a health-related condition (eg, hypertension). This review describes the FDA's evaluation of intervention and observational studies that characterize a relationship between whole grains and type 2 diabetes. This evidence-based review provides very limited evidence to support a health claim of a relationship between intake of whole grains and a reduced risk of type 2 diabetes.

FDA regulations regarding iodine addition to foods and labeling of foods containing added iodine.

The US Food and Drug Administration (FDA) regulates the addition of iodine to infant formulas, the iodization of salt, and the addition of salt and iodine to foods. The required amount of iodine in infant formulas is based on caloric content, and the label must provide the iodine content per 100 kcal. Cuprous iodide and potassium iodide may be added to table salt as a source of dietary iodine at a maximum amount of 0.01%; if added, the label must indicate that the salt is iodized. Table salt to which iodine has not been added must bear the statement, "This salt does not supply iodide, a necessary nutrient." If a nutrient is to be appropriately added to a food for the purpose of correcting a dietary insufficiency, there should be sufficient scientific information available to demonstrate a nutritional deficiency and/or identify a public health problem. Furthermore, the population groups that would benefit from the proposed fortification should be identified. If iodine is added to a food, the percent Daily Value of iodine must be listed. There are no FDA regulations governing ingredient standards for dietary supplements. As a result, some dietary supplements include iodine and others do not. If a supplement contains iodine, the Supplement Facts label must list iodine as a nutrient ingredient. If iodine is not listed on the Supplement Facts label, then it has not been added. There are similarities between the FDA, which establishes US food regulations and policies, and the Codex Alimentarius (Codex), which develops international food standards and guidelines under the aegis of the FAO and the WHO. Both the FDA and Codex call for the labeling of table salt to indicate fortification with iodine, voluntary labeling of iodine on foods, and a Daily Value (called a Nutrient Reference Value by Codex) of 150 µg for iodine.

Comparison of 2 methods for estimating the prevalences of inadequate and excessive iodine intakes.

BACKGROUND: Prevalences of iodine inadequacy and excess are usually evaluated by comparing the population distribution of urinary iodine concentration (UIC) in spot samples with established UIC cutoffs. To our knowledge, until now, dietary intake data have not been assessed for this purpose. OBJECTIVE: Our objective was to compare 2 methods for evaluating the prevalence of iodine inadequacy and excess in sex- and life stage-specific subgroups of the US population: one that uses UIC cutoffs, and one that uses iodine intake cutoffs. DESIGN: By using the iodine concentrations of foods measured in the US Food and Drug Administration's Total Diet Study (TDS), dietary intake data from the NHANES 2003-2010, and a file that maps each NHANES food to a TDS food with similar ingredients, we estimated each NHANES participant's iodine intake from each NHANES food as the mean iodine concentration of the corresponding TDS food in samples gathered over the same 2-y period. We calculated prevalences of iodine inadequacy and excess in each sex- and life stage-specific subgroup by both the UIC cutoff method and the iodine intake cutoff method-using the UIC values and dietary intakes reported for NHANES participants who provided both types of data-and compared the prevalences across methods. RESULTS: We found lower prevalences of iodine inadequacy across all sex- and life stage-specific subgroups with the iodine intake cutoff method than with the UIC cutoff method; for pregnant females, the respective prevalences were 5.0% and 37.9%. For children aged ≤8 y, the prevalence of excessive iodine intake was high by either method. CONCLUSIONS: The consideration of dietary iodine intake from all sources may provide a more complete understanding of population prevalences of iodine inadequacy and excess and thus better inform dietary guidance than consideration of UIC alone. Methods of adjusting UIC for within-person variation are needed to improve the accuracy of prevalence assessments based on UIC.

Systematic review of the evidence for an association between sugar-sweetened beverage consumption and risk of obesity.

A systematic review of the evidence for an association between sugar-sweetened beverages and risk of obesity was conducted. This review focused specifically on the role of sugar-sweetened beverages in obesity risk, taking into account energy balance. For the purpose of this review, scientific conclusions could not be drawn from the intervention studies that evaluated the relationship between sugar-sweetened beverage intake and obesity risk. Results of observational studies that examined the relationship between sugar-sweetened beverage intake and obesity risk that were adjusted for energy intake and physical activity were inconsistent for each of the three age groups evaluated (children, adolescents, and adults). From this review, evidence for an association between sugar-sweetened beverage intake and obesity risk is inconsistent when adjustment for energy balance is made.

Evidence needed to inform the next dietary reference intakes for iodine.

In 2001, Dietary Reference Intakes (DRIs) for iodine were set for the different gender and life-stage groups by the Institute of Medicine. Because of the serious consequences of iodine deficiency for the developing fetus and infant, there is particular interest in further understanding optimal iodine nutrition and improving the monitoring of iodine status, particularly during infancy, pregnancy, and lactation. This review discusses the basis for the current DRIs for iodine and the evidence that may be needed for considering and conducting the reevaluation of one or more of the DRIs.

Dietary reference intakes: cases of appropriate and inappropriate uses.

The dietary reference intakes (DRIs) are a set of reference intake levels for nutrients that can be used for planning diets and assessing nutrient inadequacies of individuals and groups. Since the publication of the DRI reports 1997-2004, the reference intake levels have been used for various purposes. While DRIs have been used appropriately for planning and assessing diets for many different situations, there have been instances in which specific DRI categories have not been applied as intended. In this review, cases are described in which DRIs were applied correctly, as well as cases from the growing number of examples in which the wrong DRI was used or DRIs were used incorrectly.

Biomarkers in nutrition: new frontiers in research and application.

Nutritional biomarkers--biochemical, functional, or clinical indices of nutrient intake, status, or functional effects--are needed to support evidence-based clinical guidance and effective health programs and policies related to food, nutrition, and health. Such indices can reveal information about biological or physiological responses to dietary behavior or pathogenic processes, and can be used to monitor responses to therapeutic interventions and to provide information on interindividual differences in response to diet and nutrition. Many nutritional biomarkers are available; yet there has been no formal mechanism to establish consensus regarding the optimal biomarkers for particular nutrients and applications.

FDA's health claim review: whey-protein partially hydrolyzed infant formula and atopic dermatitis.

In this review, we explain how the US Food and Drug Administration (FDA) used its evidence-based review system to evaluate the scientific evidence for a qualified health claim for 100% whey-protein partially hydrolyzed infant formula (W-PHF) and reduced risk of atopic dermatitis (AD). The labeling of health claims, including qualified health claims, on conventional foods and dietary supplements require premarket approval by the FDA. Health claims characterize the relationship between a substance (food or food component) and disease (eg, cancer or cardiovascular disease) or health-related condition (eg, hypertension). To determine whether sufficient evidence exists to support the qualified health claim, the FDA evaluated human intervention studies that evaluated the role of W-PHF in reducing the risk of AD. The FDA concluded there is little to very little evidence, respectively, to support a qualified health claim concerning the relationship between intake of W-PHF and a reduced risk of AD in partially breastfed and exclusively formula-fed infants throughout the first year after birth and up to 3 years of age. In addition, the FDA required a warning statement be displayed along with the health claim to indicate to consumers that partially hydrolyzed infant formulas are not hypoallergenic and should not be fed to infants who are allergic to milk or to infants with existing milk allergy symptoms.

Summary of an NIH workshop to identify research needs to improve the monitoring of iodine status in the United States and to inform the DRI.

The Office of Dietary Supplements (ODS) at the NIH sponsored a workshop on May 12-13, 2011, to bring together representatives from various NIH institutes and centers as a first step in developing an NIH iodine research initiative. The workshop also provided an opportunity to identify research needs that would inform the dietary reference intakes for iodine, which were last revised in 2001. Iodine is required throughout the life cycle, but pregnant women and infants are the populations most at risk of deficiency, because iodine is required for normal brain development and growth. The CDC monitors iodine status of the population on a regular basis, but the status of the most vulnerable populations remains uncertain. The NIH funds very little investigator-initiated research relevant to iodine and human nutrition, but the ODS has worked for several years with a number of other U.S. government agencies to develop many of the resources needed to conduct iodine research of high quality (e.g., validated analytical methods and reference materials for multiple types of samples). Iodine experts, scientists from several U.S. government agencies, and NIH representatives met for 2 d to identify iodine research needs appropriate to the NIH mission.

Tolerable upper intake levels for trans fat, saturated fat, and cholesterol.

Tolerable upper intake levels (ULs) set by the Institute of Medicine (IOM) are important, in part because they are used for estimating the percentage of the population at potential risk of adverse effects from excessive nutrient intake. The IOM did not set ULs for trans fat, saturated fat, and cholesterol because any intake level above 0% of energy increased LDL cholesterol concentration and these three food components are unavoidable in ordinary diets. The purpose of the analysis presented in this review was to evaluate clinical trial and prospective observational data that were not previously considered for setting a UL with the aim of determining whether the current UL model could be used for saturated fat, trans fat, and cholesterol. The results of this analysis confirm the limitations of the risk assessment model for setting ULs because of its inability to identify a UL for food components, such as cholesterol, that lack an intake threshold associated with increased chronic disease risk.

How the US Food and Drug Administration evaluates the scientific evidence for health claims.

Health claims describe the relationship between a substance (food or component of food) and a disease or health-related condition. They were first authorized through the Nutrition Labeling and Education Act of 1990. The standard set by the US Congress for the scientific evidence required to authorize a claim was the significant scientific agreement standard. This strong standard was challenged by several manufacturers of dietary supplements. Several court decisions directed the US Food and Drug Administration (FDA) to provide for dietary supplement claims not meeting the significant scientific agreement standard by adding a disclaimer to the claim that would eliminate the claim's potential to be misleading. In December 2002, the FDA announced a major new initiative, "The Consumer Health Information for Better Nutrition Initiative," which, among other things, provided for the use of qualified health claims for both conventional foods and dietary supplements. The process for reviewing the scientific evidence for a claim reaching significant scientific agreement and for those that require qualifying language is the same. In January 2009, the FDA issued a guidance document entitled "Evidence-Based Review System for the Scientific Evaluation of Health Claims." The process used by the FDA to review the scientific evidence for health claims and qualified health claims are described in this article.