Analytic methods for understanding the temporal patterning of dietary and 24-hour movement behaviours: a scoping review.

Dietary and movement behaviours (physical activity [PA], sedentary behaviour [SED], and sleep) occur throughout a 24-hour day and involve multiple contexts. Understanding the temporal patterning of these 24-hour behaviours and their contextual determinants is key to determining their combined effect on health. A scoping review was conducted to identify novel analytic methods for determining temporal behaviour patterns and their contextual correlates. We searched Embase, ProQuest and EBSCOhost databases in July 2022 to identify studies published between 1997 and 2022 on temporal patterns and their contextual correlates (e.g., locational, social, environmental, personal). We included 14 studies after title and abstract (n=33,292) and full-text (n=135) screening, of which 11 were published after 2018. Most studies (n=4 in adults; n=5 in children and adolescents), examined waking behaviour patterns (i.e., both PA and SED) of which three also included sleep and six included contextual correlates. PA and diet were examined together in only one study of adults. Contextual correlates of dietary, PA and sleep temporal behaviour patterns were also examined. Machine learning with various clustering algorithms and model-based clustering techniques were most used to determine 24-hourly temporal behaviour patterns. While the included studies used a diverse range of methods, behavioural variables and assessment time periods, results showed that temporal patterns characterised by high SED and low PA were linked to poorer health outcomes, compared to those with low SED and high PA. This review identified temporal behaviour patterns, and their contextual correlates, that were associated with adiposity and cardiometabolic disease risk suggesting these methods hold promise for the discovery of holistic lifestyle exposures important to health. Standardised reporting of methods and patterns and multidisciplinary collaboration between nutrition, physical activity and sleep researchers, statisticians, and computer scientists were identified as key pathways to advance future research on temporal behaviour patterns in relation to health.

Bullying Victimization and Adverse Childhood Experiences: Retrospective Reports of Relative Impact on Emotional Distress.

The literature suggests that there is a significant overlap in definition, measurement, and outcomes between trauma and bullying victimization, but the relative impact on current emotional distress of these events has not been explored. The goal of the current study was to explore whether traditional and cyber bullying victimization has a similar negative impact on current emotional disrtresss as other adverse childhood experiences which may also lead to a traumatic response. In addition, this study examined whether the association between bullying victimization and emotional distress is exacerbated when individuals also experience additional ACEs. Retrospective reports from a diverse sample of 576 adults were collected via an online survey. When ranked against other ACEs such as viewing family mental health problems or substance abuse, or verbal, physical, emotional, and sexual victimization not from peers, nearly 30% of participants ranked bullying victimization as having the most negative impact on their levels of emotional distress. Multi-group path analyses indicated that experiencing additional ACEs seems to exacerbate distress caused by bullying and cyber bullying victimization. The current study suggests that bullying victimization may be just as detrimental as other types of ACEs that occur in childhood.

Novel Anti-virulence Compounds Disrupt Exotoxin Expression in MRSA.

Hemolysins are lytic exotoxins expressed in most strains of S. aureus , but hemolytic activity varies between strains. We have previously reported several novel anti-virulence compounds that disrupt the S. aureus transcriptome, including hemolysin gene expression. This report delves further into our two lead compounds, loratadine and a structurally related brominated carbazole, and their effects on hemolysin production in MRSA. To gain understanding into how these compounds affect hemolysis, we analyzed these exotoxins at the DNA, RNA, and protein level after in vitro treatment. While lysis of red blood cells varied between strains, DNA sequence variation did not account for it. We hypothesized that our compounds would modulate gene expression of multiple hemolysins in a laboratory strain and a clinically relevant hospital-acquired strain of MRSA, both with SCC mec type II. RNA-seq analysis of differential gene expression in untreated and compound-treated cultures revealed hundreds of differentially expressed genes, with a significant enrichment in genes involved in hemolysis. The brominated carbazole and loratadine both displayed the ability to reduce hemolysis in the laboratory strain, but displayed differential activity in a hospital-acquired strain. These results corroborate gene expression studies as well as western blots of alpha hemolysin. Together, this work suggests that small molecules may alter exotoxin production in MRSA, but that the directionality and/or magnitude of the difference is likely strain-dependent.

Corrigendum: A community focused approach toward making healthy and affordable daily diet recommendations.

[This corrects the article DOI: 10.3389/fdata.2023.1086212.].

Expression of USP25 associates with fibrosis, inflammation and metabolism changes in IgG4-related disease.

IgG4-related disease (IgG4-RD) has complex clinical manifestations ranging from fibrosis and inflammation to deregulated metabolism. The molecular mechanisms underpinning these phenotypes are unclear. In this study, by using IgG4-RD patient peripheral blood mononuclear cells (PBMCs), IgG4-RD cell lines and Usp25 knockout mice, we show that ubiquitin-specific protease 25 (USP25) engages in multiple pathways to regulate fibrotic and inflammatory pathways that are characteristic to IgG4-RD. Reduced USP25 expression in IgG4-RD leads to increased SMAD3 activation, which contributes to fibrosis and induces inflammation through the IL-1ß inflammatory axis. Mechanistically, USP25 prevents ubiquitination of RAC1, thus, downregulation of USP25 leads to ubiquitination and degradation of RAC1. Decreased RAC1 levels result in reduced aldolase A release from the actin cytoskeleton, which then lowers glycolysis. The expression of LYN, a component of the B cell receptor signalosome is also reduced in USP25-deficient B cells, which might result in B cell activation deficiency. Altogether, our results indicate a potential anti-inflammatory and anti-fibrotic role for USP25 and make USP25 a promising diagnostic marker and potential therapeutic target in IgG4-RD.

Workshop summary: building an NHANES for the future.

The American Society for Nutrition's (ASN) Committee on Advocacy and Science Policy (CASP) organized a workshop, "Building a National Health and Nutrition Examination Survey (NHANES) for the Future," held during NUTRITION 2023, which took place in Boston, MA in July 2023. CASP had already identified an urgent need for increased support and modernization to ensure that a secure future for NHANES is achievable. The survey faces challenges associated with data collection, stagnant funding, and a need for more granular data for subpopulations and groups at risk. The workshop provided an overview of NHANES, including the nutrition component, and the many other uses for the survey's data, which extend beyond nutrition. Speakers highlighted NHANES's current and emerging challenges, as well as possible solutions to address these challenges, especially with regard to response rates of underrepresented groups, linkage of survey data to other resources, incorporation of new survey methodologies, and emerging data needs. The workshop also included a "Town Hall" component to gather additional feedback on NHANES' challenges and proposed solutions from audience members. The workshop provided many possible action items that ASN will explore and use to inform effective continued advocacy in support of NHANES and to find possible opportunities for ASN and others to partner with the Centers for Disease Control and Prevention National Center for Health Statistics to strengthen this vital survey and maintain its robust and relevant data moving forward.

The role of the community café in addressing food security: Perceptions of managers and directors.

In the United States, the pay-what-you-can restaurant model (community cafes) is an increasingly popular approach to addressing food insecurity in local communities. We conducted semi-structured interviews (n = 13) with community café executive managers and directors to assess their perceptions of the role that their cafes play in addressing food security (FS). Analysis of interviews revealed two major areas of emphasis by participants. Filling an unoccupied space in the food security landscape. Interviewees regularly cited the goal of making meals available through a dependable schedule, convenient location, and welcoming atmosphere for guests to promote regular visits to the café, and they did so with an awareness of how their practices were shaped by perceived shortcomings in comparable services. In addition, guest agency and social aspects of the café as components of utilization, was another major area. Interviewees often regarded the opportunity of the food insecure guest to choose healthy options (i.e., nutritionally dense) over less healthful ones (i.e., calorically dense) from the menu as a critical component of their service. The social component of the café (e.g., community atmosphere, 'dining-out' experience) was another aspect of the café's function that promoted dignity for the guest which can lead to greater likelihood of return visits. Perceptions shared by participants of the café's role in addressing food security suggest that rather than simply adding to the available options of hunger relief services, the café model attempts to address many areas of concern, such as structural and cultural barriers, found in the traditional forms of charitable food provision.

The characterization of CD8+ T-cell responses in COVID-19.

This review gives an overview of the protective role of CD8+ T cells in SARS-CoV-2 infection. The cross-reactive responses intermediated by CD8+ T cells in unexposed cohorts are described. Additionally, the relevance of resident CD8+ T cells in the upper and lower airway during infection and CD8+ T-cell responses following vaccination are discussed, including recent worrisome breakthrough infections and variants of concerns (VOCs). Lastly, we explain the correlation between CD8+ T cells and COVID-19 severity. This review aids in a deeper comprehension of the association between CD8+ T cells and SARS-CoV-2 and broadens a vision for future exploration.

Loratadine Combats Methicillin-Resistant Staphylococcus aureus by Modulating Virulence, Antibiotic Resistance, and Biofilm Genes.

Methicillin-resistant Staphylococcus aureus (MRSA) has evolved to become resistant to multiple classes of antibiotics. New antibiotics are costly to develop and deploy, and they have a limited effective lifespan. Antibiotic adjuvants are molecules that potentiate existing antibiotics through nontoxic mechanisms. We previously reported that loratadine, the active ingredient in Claritin, potentiates multiple cell-wall active antibiotics in vitro and disrupts biofilm formation through a hypothesized inhibition of the master regulatory kinase Stk1. Loratadine and oxacillin combined repressed the expression of key antibiotic resistance genes in the bla and mec operons. We hypothesized that additional genes involved in antibiotic resistance, biofilm formation, and other cellular pathways would be modulated when looking transcriptome-wide. To test this, we used RNA-seq to quantify transcript levels and found significant effects in gene expression, including genes controlling virulence, antibiotic resistance, metabolism, transcription (core RNA polymerase subunits and sigma factors), and translation (a plethora of genes encoding ribosomal proteins and elongation factor Tu). We further demonstrated the impacts of these transcriptional effects by investigating loratadine treatment on intracellular ATP levels, persister formation, and biofilm formation and morphology. Loratadine minimized biofilm formation in vitro and enhanced the survival of infected Caenorhabditis elegans. These pleiotropic effects and their demonstrated outcomes on MRSA virulence and survival phenotypes position loratadine as an attractive anti-infective against MRSA.

Temporal Dietary Pattern Cluster Membership Varies on Weekdays and Weekends but Both Link to Health.

BACKGROUND: Energy and dietary quality are known to differ between weekdays and weekends. Data-driven approaches that incorporate time, amount, and duration of dietary intake have previously been used to partition participants' daily weekday dietary intake time series into clusters representing weekday temporal dietary patterns (TDPs) linked to health indicators in United States adults. Yet, neither the relationship of weekend day TDPs to health indicators nor how the TDP membership may change from weekday to weekend is known. OBJECTIVES: This study was conducted to determine the association between TDPs on weekdays and weekend days and health indicators [diet quality, waist circumference (WC), body mass index (BMI), and obesity] and their overlap among participants. METHODS: A weekday and weekend day 24-hour dietary recall of 9494 nonpregnant United States adults aged 20-65 years from the cross-sectional National Health and Nutrition Examination Survey 2007-2018 was used to determine the timing and amount of energy intake. Modified dynamic time warping and kernel k-means algorithm clustered participants into 4 TDPs on weekdays and weekend days. Multivariate regression models determined the associations between TDPs and health indicators, controlling for potential confounders and adjusting for the survey design and multiple comparisons. The percentages of overlap in cluster membership between TDPs on weekdays and weekend days were also determined. RESULTS: United States adults with a TDP of evenly spaced, energy-balanced eating occasions, representing the TDP of more than one-third of all adults on weekdays and weekends, had significantly higher diet quality, lower BMI, WC, and odds of obesity when compared to those with other TDPs. Membership of most United States adults to TDPs varied from weekdays to weekends. CONCLUSIONS: Both weekday and weekend TDPs were significantly associated with health indicators. TDP membership of most United States adults was not consistent on weekdays and weekends.

Dietary Intakes of Community-Dwelling Adults in the United States across Older Adulthood: National Health and Nutrition Examination Survey 2015-March 2020.

BACKGROUND: Dietary guidance is set on the basis of age and life stage and defines older adults as ≥60 y. Yet, little is known about if and/or how diet quality differs beyond the age of 60. OBJECTIVE: The objective of this study was to compare the dietary intakes of 60-69 (n = 2079), 70-79 (n = 1181), and 80+ y old (n = 644) noninstitutionalized men and women in the United States using the Healthy Eating Index 2015 (HEI) and the What We Eat in America food categories. METHODS: Data were obtained from National Health and Nutrition Examination Survey 2015-2016 and 2017-March 2020. HEI and component scores were calculated using the population ratio method. Population estimates for dietary intake were calculated as the average reported over 2 separate nonconsecutive 24-h dietary recalls. RESULTS: In men and women, the reported energy intake was lower among the 80+ y olds (kcal/d men-80+: 1884 ± 30, 70-79: 2022 ± 33, 60-69: 2142 ± 39; women-80+: 1523 ± 36; 70-79: 1525 ± 33, 60-69: 1650 ± 25; P-trend < 0.001). Total HEI scores did not differ significantly across the 3 age categories, but the 80+ y olds had significantly lower scores for the green vegetables and beans component than the 60-69 y olds [men-mean (95% confidence interval): 2.0 (1.5, 2.5) compared with 3.4 (2.6, 4.1); women-2.3 (1.8, 2.8) compared with 4.4 (3.7, 5.0)]. In women, the percentage of daily calories from protein was significantly lower in the 80+ y olds than in the 60-69 and 70-79 y olds (12.9% ± 0.6%, compared with 17.0% ± 0.9% and 15.6% ± 0.6%, respectively). Protein intake did not differ significantly among the 3 age groups in men. The 80+ y old men and women reported consuming a significantly higher percentage of calories from snacks and sweets compared with the 60-69 y olds (men-80+: 18.1% ± 0.8%, 60-69: 15.4% ± 0.7%; women-80+: 19.6% ± 0.8%, 60-69: 15.5% ± 0.7%). CONCLUSION: The diet of 80+ y olds differed from that of 60-69 y olds in some key components, including energy, snacks and sweets, protein, and green vegetables. Future research is needed to determine if there are health-related consequences to these differences.

OvaPrint-A Cell-free DNA Methylation Liquid Biopsy for the Risk Assessment of High-grade Serous Ovarian Cancer.

PURPOSE: High-grade serous ovarian carcinoma (HGSOC) is the most lethal epithelial ovarian cancer (EOC) and is often diagnosed at late stage. In women with a known pelvic mass, surgery followed by pathologic assessment is the most reliable way to diagnose EOC and there are still no effective screening tools in asymptomatic women. In the current study, we developed a cell-free DNA (cfDNA) methylation liquid biopsy for the risk assessment of early-stage HGSOC. EXPERIMENTAL DESIGN: We performed reduced representation bisulfite sequencing to identify differentially methylated regions (DMR) between HGSOC and normal ovarian and fallopian tube tissue. Next, we performed hybridization probe capture for 1,677 DMRs and constructed a classifier (OvaPrint) on an independent set of cfDNA samples to discriminate HGSOC from benign masses. We also analyzed a series of non-HGSOC EOC, including low-grade and borderline samples to assess the generalizability of OvaPrint. A total of 372 samples (tissue n = 59, plasma n = 313) were analyzed in this study. RESULTS: OvaPrint achieved a positive predictive value of 95% and a negative predictive value of 88% for discriminating HGSOC from benign masses, surpassing other commercial tests. OvaPrint was less sensitive for non-HGSOC EOC, albeit it may have potential utility for identifying low-grade and borderline tumors with higher malignant potential. CONCLUSIONS: OvaPrint is a highly sensitive and specific test that can be used for the risk assessment of HGSOC in symptomatic women. Prospective studies are warranted to validate OvaPrint for HGSOC and further develop it for non-HGSOC EOC histotypes in both symptomatic and asymptomatic women with adnexal masses.

Integration of USDA Food Classification System and Food Composition Database for Image-Based Dietary Assessment among Individuals Using Insulin.

New imaging technologies to identify food can reduce the reporting burden of participants but heavily rely on the quality of the food image databases to which they are linked to accurately identify food images. The objective of this study was to develop methods to create a food image database based on the most commonly consumed U.S. foods and those contributing the most to energy. The objective included using a systematic classification structure for foods based on the standardized United States Department of Agriculture (USDA) What We Eat in America (WWEIA) food classification system that can ultimately be used to link food images to a nutrition composition database, the USDA Food and Nutrient Database for Dietary Studies (FNDDS). The food image database was built using images mined from the web that were fitted with bounding boxes, identified, annotated, and then organized according to classifications aligning with USDA WWEIA. The images were classified by food category and subcategory and then assigned a corresponding USDA food code within the USDA's FNDDS in order to systematically organize the food images and facilitate a linkage to nutrient composition. The resulting food image database can be used in food identification and dietary assessment.

Temporal Patterns of Diet and Physical Activity and of Diet Alone Have More Numerous Relationships With Health and Disease Status Indicators Compared to Temporal Patterns of Physical Activity Alone.

BACKGROUND: Daily temporal patterns of energy intake (temporal dietary patterns [TDPs]) and physical activity (temporal physical activity patterns [TPAPs]) have been independently and jointly (temporal dietary and physical activity patterns [TDPAPs]) associated with health and disease status indicators. OBJECTIVE: The aim of this study was to compare the number and strength of association between clusters of daily TDPs, TPAPs, and TDPAPs and multiple health and disease status indicators. DESIGN: This cross-sectional study used 1 reliable weekday dietary recall and 1 random weekday of accelerometer data to partition to create clusters of participants representing the 3 temporal patterns. Four clusters were created via kernel-k means clustering algorithm of the same constrained dynamic time warping distance computed over the time series for each temporal pattern. PARTICIPANTS/SETTING: From the National Health and Nutrition Examination Survey (2003-2006), 1,836 US adults aged 20 through 65 years who were not pregnant and had valid diet, physical activity, sociodemographic, anthropometric, questionnaire, and health and disease status indicator data were included. MAIN OUTCOME MEASURES: Health status indicators used as outcome measures were body mass index, waist circumference, fasting plasma glucose, hemoglobin A1c, triglycerides, high-density lipoprotein cholesterol, total cholesterol, and systolic and diastolic blood pressure; disease status indicators included obesity, type 2 diabetes mellitus, and metabolic syndrome. STATISTICAL ANALYSES PERFORMED: Multivariate regression models determined associations between the clusters representing each pattern and health and disease status indicators, controlling for confounders and adjusting for multiple comparisons. The number of significant differences among clusters and adjusted R2 and Akaike information criterion compared the strength of associations between clusters of patterns and continuous and categorical health and disease status indicators. RESULTS: TDPAPs showed 21 significant associations with health and disease status indicators, including body mass index, waist circumference, obesity, and type 2 diabetes; TDPs showed 19 significant associations; and TPAPs showed 8 significant associations. CONCLUSIONS: TDPAPs and TDPs had stronger and more numerous associations with health and disease status indicators compared with TPAPs. Patterns representing the integration of daily dietary habits hold promise for early detection of obesity.

Usual nutrient intakes and diet quality among United States older adults participating in the Supplemental Nutrition Assistance Program compared with income-eligible nonparticipants.

BACKGROUND: The proportion of older adults with food insecurity at 8% has increased faster than that of the general United States population from 2001 to 2017. Many low-income food-insecure older adults rely on food-assistance programs, such as the Supplemental Nutrition Assistance Program (SNAP), for meeting energy and nutrient needs, whereas others are eligible but do not participate. Neither updated nutrient intake estimates nor potential differences in meeting the Dietary Reference Intakes from foods alone and with dietary supplements (DS) among low-income older adults using or eligible for SNAP are known. OBJECTIVES: This study assessed and compared national estimates of usual nutrient adequacy and dietary quality of United States older adults using SNAP and income-eligible nonparticipants. METHODS: Usual dietary intake was estimated among older adults (≥60 y; n = 2582) in the 2007-2016 NHANES cross-sectional national survey. Data on food-assistance participation and eligibility (poverty-income-ratio ≤130%), DS use, and ≥24-h dietary recalls were used. The NCI method (Markov Chain Monte Carlo approach) was applied to estimate mean usual nutrient intakes, proportion of inadequate nutrient intake, and dietary quality using the 2015 Healthy Eating Index. RESULTS: Neither usual nutrient intake from dietary and total sources nor dietary quality differed between older adult SNAP participants and eligible nonparticipants. Low dietary quality and high percentage of inadequate intake for several nutrients were apparent among both groups, especially from food sources alone, including vitamins A (56%), C (55%), D (97%), E (99%), calcium (73%), and magnesium (74%), but rates were attenuated when DS were also considered (i.e., 36% reduced risk for vitamin D inadequacy). CONCLUSIONS: Diet quality and usual nutrient intake among older adult SNAP participants and eligible nonparticipants were poor, but DS lowered the risk of nutrient inadequacy. Future policies and programs should focus on improving the intake of vitamins A, C, D, E, calcium, and magnesium and dietary quality for all older adults.

The role of regulatory T cells and follicular T helper cells in HBV infection.

Hepatitis B has become one of the major global health threats, especially in developing countries and regions. Hepatitis B virus infection greatly increases the risk for liver diseases such as cirrhosis and cancer. However, treatment for hepatitis B is limited when considering the huge base of infected people. The immune response against hepatitis B is mediated mainly by CD8+ T cells, which are key to fighting invading viruses, while regulatory T cells prevent overreaction of the immune response process. Additionally, follicular T helper cells play a key role in B-cell activation, proliferation, differentiation, and formation of germinal centers. The pathogenic process of hepatitis B virus is generally the result of a disorder or dysfunction of the immune system. Therefore, we present in this review the critical functions and related biological processes of regulatory T cells and follicular T helper cells during HBV infection.

The role of Raptor in lymphocytes differentiation and function.

Raptor, a key component of mTORC1, is required for recruiting substrates to mTORC1 and contributing to its subcellular localization. Raptor has a highly conserved N-terminus domain and seven WD40 repeats, which interact with mTOR and other mTORC1-related proteins. mTORC1 participates in various cellular events and mediates differentiation and metabolism. Directly or indirectly, many factors mediate the differentiation and function of lymphocytes that is essential for immunity. In this review, we summarize the role of Raptor in lymphocytes differentiation and function, whereby Raptor mediates the secretion of cytokines to induce early lymphocyte metabolism, development, proliferation and migration. Additionally, Raptor regulates the function of lymphocytes by regulating their steady-state maintenance and activation.

Long-Tailed Food Classification.

Food classification serves as the basic step of image-based dietary assessment to predict the types of foods in each input image. However, foods in real-world scenarios are typically long-tail distributed, where a small number of food types are consumed more frequently than others, which causes a severe class imbalance issue and hinders the overall performance. In addition, none of the existing long-tailed classification methods focus on food data, which can be more challenging due to the inter-class similarity and intra-class diversity between food images. In this work, two new benchmark datasets for long-tailed food classification are introduced, including Food101-LT and VFN-LT, where the number of samples in VFN-LT exhibits real-world long-tailed food distribution. Then, a novel two-phase framework is proposed to address the problem of class imbalance by (1) undersampling the head classes to remove redundant samples along with maintaining the learned information through knowledge distillation and (2) oversampling the tail classes by performing visually aware data augmentation. By comparing our method with existing state-of-the-art long-tailed classification methods, we show the effectiveness of the proposed framework, which obtains the best performance on both Food101-LT and VFN-LT datasets. The results demonstrate the potential to apply the proposed method to related real-life applications.

A Scoping Review of Household Factors Contributing to Dietary Quality and Food Security in Low-Income Households with School-Age Children in the United States.

Low-income and food-insecure households are at risk of poor dietary quality and even more severe food insecurity. Especially in childhood, consuming a nutritionally adequate diet is an essential driver of health, growth, and development. Household-level factors can present challenges to support the nutritional needs of low-income and food-insecure household members. The aim of this scoping review is to identify the contributing household factors to dietary quality and food security in US households of school-aged children 5 to 19 years and synthesize the evidence around emergent themes for application to future interventions. The scoping review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols Extension for Scoping Reviews using search terms addressing food insecurity, low income, and dietary behaviors in the database PubMed. Screening by 3 independent reviewers of the title, abstract, and full study phases identified 44 studies. The 5 themes around which the studies grouped were: parental behaviors, child/adolescent behaviors, food procurement behaviors, food preparation behaviors, and household environment factors. Most studies were cross-sectional (n = 41, 93%) and focused on parental behaviors (n = 31, 70%), followed by food preparation and procurement behaviors. The themes identified were interrelated and suggest that incorporating education on parent and child behaviors that influence food procurement and preparation, along with strengthening organization and planning in the household environment, may hold promise to improve dietary quality and food security among food-insecure and low-income households. The findings can be used to inform future nutrition education interventions aimed at improving dietary quality and food security in households with school-aged children.

Major Gaps in Understanding Dietary Supplement Use in Health and Disease.

Precise dietary assessment is critical for accurate exposure classification in nutritional research, typically aimed at understanding how diet relates to health. Dietary supplement (DS) use is widespread and represents a considerable source of nutrients. However, few studies have compared the best methods to measure DSs. Our literature review on the relative validity and reproducibility of DS instruments in the United States [e.g., product inventories, questionnaires, and 24-h dietary recalls (24HR)] identified five studies that examined validity (n = 5) and/or reproducibility (n = 4). No gold standard reference method exists for validating DS use; thus, each study's investigators chose the reference instrument used to measure validity. Self-administered questionnaires agreed well with 24HR and inventory methods when comparing the prevalence of commonly used DSs. The inventory method captured nutrient amounts more accurately than the other methods. Reproducibility (over 3 months to 2.4 years) of prevalence of use estimates on the questionnaires was acceptable for common DSs. Given the limited body of research on measurement error in DS assessment, only tentative conclusions on these DS instruments can be drawn at present. Further research is critical to advancing knowledge in DS assessment for research and monitoring purposes.