1
|
Mori N, Murphy N, Sawada N, Achaintre D, Yamaji T, Scalbert A, Ishihara J, Takachi R, Nakamura K, Tanaka J, Iwasaki M, Iso H, Inoue M, Gunter MJ, Tsugane S. Reproducibility and dietary correlates of plasma polyphenols in the JPHC-NEXT Protocol Area study. Eur J Clin Nutr 2024; 78:34-42. [PMID: 37891229 DOI: 10.1038/s41430-023-01349-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 09/18/2023] [Accepted: 09/20/2023] [Indexed: 10/29/2023]
Abstract
BACKGROUND In recent years, an increasing number of epidemiological studies have suggested a role of polyphenols in the prevention of chronic diseases. Prospective cohort studies have typically measured polyphenol concentrations in a single blood sample and the reproducibility of plasma polyphenol measurements is largely unknown. OBJECTIVE We evaluated the reproducibility of 35 plasma polyphenols collected at an interval of 1-year. We also examined correlations of these polyphenols with food group intakes calculated from weighed food records (WFR) and food frequency questionnaire (FFQ). METHODS The study included 227 middle-aged participants from the JPHC-NEXT Protocol Area in Japan. We measured 35 polyphenols in plasma collected at two points 1-year apart. Food group intakes were calculated from 12-day WFR and FFQ. For the reproducibility analysis, the intraclass correlation coefficient (ICC) of 35 polyphenol concentrations were examined between the two points. Pearson's partial correlations was used to assess the correlation between polyphenols and food groups. RESULTS Moderate- to high ICCs were observed for tea-originated polyphenols such as gallic acid, quercetin, epigallocatechin, and kaempferol - and coffee-derived polyphenols, such as caffeic acid, and ferulic acid. For the dietary analyses, moderate correlations were observed for non-alcoholic beverages intake and epigallocatechin, epicatechin, catechin, and gallic acid. For green tea, higher correlations were observed with these polyphenols. CONCLUSION Plasma concentrations of tea and coffee-related polyphenols, except for catechin, had good reproducibility over a 1-year period. The correlations between intake of non-alcoholic beverages, particularly green tea, and tea polyphenols, indicated moderate- to high correlations.
Collapse
Affiliation(s)
- Nagisa Mori
- Nutrition and Metabolism Branch, International Agency for Research on Cancer (IARC/WHO), Lyon, France.
- Division of Cohort Research, National Cancer Center Institute for Cancer Control, National Cancer Center, Tokyo, Japan.
- Section of Nutritional Epidemiology, Department of Nutritional Epidemiology and Shokuiku, National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, Osaka, Japan.
| | - Neil Murphy
- Nutrition and Metabolism Branch, International Agency for Research on Cancer (IARC/WHO), Lyon, France
| | - Norie Sawada
- Division of Cohort Research, National Cancer Center Institute for Cancer Control, National Cancer Center, Tokyo, Japan
| | - David Achaintre
- Nutrition and Metabolism Branch, International Agency for Research on Cancer (IARC/WHO), Lyon, France
- School of Plant Science and Food Security, Tel Aviv University, Tel Aviv, Israel
| | - Taiki Yamaji
- Division of Epidemiology, National Cancer Center Institute for Cancer Control, National Cancer Center, Tokyo, Japan
| | - Augustin Scalbert
- Nutrition and Metabolism Branch, International Agency for Research on Cancer (IARC/WHO), Lyon, France
| | - Junko Ishihara
- Graduate School of Environmental Health, Azabu University, Kanagawa, Japan
| | - Ribeka Takachi
- Department of Food Science and Nutrition, Nara Women's University Graduate School of Humanities and Sciences, Nara, Japan
| | - Kazutoshi Nakamura
- Division of Preventive Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Junta Tanaka
- Department of Health Promotion Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Motoki Iwasaki
- Division of Epidemiology, National Cancer Center Institute for Cancer Control, National Cancer Center, Tokyo, Japan
| | - Hiroyasu Iso
- Institute of Global Health Policy Research, Bureau of International Health Cooperation, National Center for Global Health and Medicine, Tokyo, Japan
| | - Manami Inoue
- Division of Prevention, National Cancer Center Institute for Cancer Control, National Cancer Center, Tokyo, Japan
| | - Marc J Gunter
- Nutrition and Metabolism Branch, International Agency for Research on Cancer (IARC/WHO), Lyon, France
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, United Kingdom
| | - Shoichiro Tsugane
- Division of Cohort Research, National Cancer Center Institute for Cancer Control, National Cancer Center, Tokyo, Japan
- Graduate School of Public Health, International University of Health and Welfare, Tokyo, Japan
| |
Collapse
|
2
|
Rizzolo-Brime L, Caro-Garcia EM, Alegre-Miranda CA, Felez-Nobrega M, Zamora-Ros R. Lignan exposure: a worldwide perspective. Eur J Nutr 2021; 61:1143-1165. [PMID: 34799775 DOI: 10.1007/s00394-021-02736-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 11/03/2021] [Indexed: 10/19/2022]
Abstract
Dietary lignans are phytoestrogens that are mostly found in plant-based foods, especially whole grains, seeds, nuts, legumes and vegetables. An accurate assessment of lignan exposure is crucial to evaluate their potential health benefits and to establish future recommendations and dietary guidelines. This narrative review aimed to (i) summarize the pros and the cons of the current main assessment methods for lignan exposure─i.e., dietary questionnaires, food composition tables and biomarkers, (ii) describe the individual lignans more consumed from a worldwide perspective, as well as their main food sources, (iii) determine the lignans concentrations in both urine and blood, and explore their heterogeneity among countries, and finally (iv) discuss the main determinants of lignan exposure.
Collapse
Affiliation(s)
- Lucia Rizzolo-Brime
- Unit of Nutrition and Cancer, Cancer Epidemiology Research Program, Catalan Institute of Oncology, Bellvitge Biomedical Research Institute (IDIBELL), Av Gran Via 199-203, 08908, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Elida M Caro-Garcia
- Unit of Nutrition and Cancer, Cancer Epidemiology Research Program, Catalan Institute of Oncology, Bellvitge Biomedical Research Institute (IDIBELL), Av Gran Via 199-203, 08908, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Cynthia A Alegre-Miranda
- Unit of Nutrition and Cancer, Cancer Epidemiology Research Program, Catalan Institute of Oncology, Bellvitge Biomedical Research Institute (IDIBELL), Av Gran Via 199-203, 08908, L'Hospitalet de Llobregat, Barcelona, Spain
| | | | - Raul Zamora-Ros
- Unit of Nutrition and Cancer, Cancer Epidemiology Research Program, Catalan Institute of Oncology, Bellvitge Biomedical Research Institute (IDIBELL), Av Gran Via 199-203, 08908, L'Hospitalet de Llobregat, Barcelona, Spain.
| |
Collapse
|
3
|
Xu Y, Le Sayec M, Roberts C, Hein S, Rodriguez-Mateos A, Gibson R. Dietary Assessment Methods to Estimate (Poly)phenol Intake in Epidemiological Studies: A Systematic Review. Adv Nutr 2021; 12:1781-1801. [PMID: 33684195 PMCID: PMC8483972 DOI: 10.1093/advances/nmab017] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 01/06/2021] [Accepted: 01/29/2021] [Indexed: 11/25/2022] Open
Abstract
Nutritional epidemiological studies have frequently reported associations between higher (poly)phenol intake and a decrease in the risk or incidence of noncommunicable diseases. However, the assessment methods that have been used to quantify the intakes of these compounds in large-population samples are highly variable. This systematic review aims to characterize the methods used to assess dietary (poly)phenol intake in observational studies, report the validation status of the methods, and give recommendations on method selection and data reporting. Three databases were searched for publications that have used dietary assessment methods to measure (poly)phenol intake and 549 eligible full texts were identified. Food-frequency questionnaires were found to be the most commonly used tool to assess dietary (poly)phenol intake (73%). Published data from peer-reviewed journals were the major source of (poly)phenol content data (25%). An increasing number of studies used open-access databases such as Phenol-Explorer and USDA databases on flavonoid content since their inception, which accounted for 11% and 23% of the data sources, respectively. Only 16% of the studies reported a method that had been validated for measuring the target (poly)phenols. For future research we recommend: 1) selecting a validated dietary assessment tool according to the target compounds and target period of measurement; 2) applying and combining comprehensive (poly)phenol content databases such as USDA and Phenol-Explorer; 3) detailing the methods used to assess (poly)phenol intake, including dietary assessment method, (poly)phenol content data source; 4) follow the Strengthening the Reporting of Observational Studies in Epidemiology-Nutritional Epidemiology (STROBE-nut) framework; and 5) complementing dietary intake assessment based on questionnaires with measurement of (poly)phenols in biofluids using appropriate and validated analytical methods.
Collapse
Affiliation(s)
- Yifan Xu
- Department of Nutritional Sciences, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Melanie Le Sayec
- Department of Nutritional Sciences, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Caroline Roberts
- Department of Nutritional Sciences, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Sabine Hein
- Department of Nutritional Sciences, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom,School of Psychology and Clinical Language Sciences, University of Reading, Reading, United Kingdom
| | | | | |
Collapse
|
4
|
Kumar NB, Pow-Sang J, Spiess P, Dickinson S, Schell MJ. A phase II randomized clinical trial using aglycone isoflavones to treat patients with localized prostate cancer in the pre-surgical period prior to radical prostatectomy. Oncotarget 2020; 11:1218-1234. [PMID: 32292572 PMCID: PMC7147089 DOI: 10.18632/oncotarget.27529] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 03/03/2020] [Indexed: 01/11/2023] Open
Abstract
Prostate cancer (PCa) is the most common cancer in American men. Additionally, African American Men (AAM) are 60% more likely to be diagnosed with PCa and 2.4 times more likely to die from this disease compared to Caucasian men (CM). To date, there are few strategies effective for chemoprevention for men with localized PCa. There is thus a need to continue to evaluate agents and strategies for chemoprevention of prostate cancer. Epidemiological, laboratory and early phase clinical trials have shown that the isoflavones modulates several biomarkers implicated in prostate carcinogenesis. The goal of this phase II randomized clinical trial was to explore the comparative effectiveness and safety of 40 mgs of aglycone isoflavones in AAM and CM with localized PCa in the pre-surgical period prior to radical prostatectomy. Thirty six participants (25 CM, 6AAM) were randomized to the isoflavone arm and 34 (25 CM, 7AAM) to the placebo arm, with 62 completing the intervention. Results indicated that isoflavones at a dose of 20 mgs BID for 3-6 weeks was well tolerated but did not reduce tissue markers of proliferation. A significant reduction in serum PSA was observed with isoflavone supplementation in CM compared to the placebo arm, but not observed in AAM. We observed no changes in serum steroid hormones with isoflavone supplementation. In AAM, a reduction in serum IGF-1 concentrations and IGF1: IGFBP-3 ratios were observed with isoflavone supplementation. Well-powered studies for longer duration of intervention may inform future trials with isoflavones, for chemoprevention of PCa.
Collapse
Affiliation(s)
- Nagi B Kumar
- Cancer Epidemiology, H. Lee Moffitt Cancer Center and Research Institute, Inc., Tampa, FL, USA
| | - Julio Pow-Sang
- Department of Urology, H. Lee Moffitt Cancer Center and Research Institute, Inc., Tampa, FL, USA
| | - Philippe Spiess
- Department of Urology, H. Lee Moffitt Cancer Center and Research Institute, Inc., Tampa, FL, USA
| | - Shohreh Dickinson
- Department of Pathology, H. Lee Moffitt Cancer Center and Research Institute, Inc., Tampa, FL, USA
| | - Michael J Schell
- Department of Biostatistics, H. Lee Moffitt Cancer Center and Research Institute, Inc., Tampa, FL, USA
| |
Collapse
|
5
|
Heras-González L, Latorre J, Martinez-Bebia M, Espino D, Olea-Serrano F, Mariscal-Arcas M. The relationship of obesity with lifestyle and dietary exposure to endocrine-disrupting chemicals. Food Chem Toxicol 2020; 136:110983. [DOI: 10.1016/j.fct.2019.110983] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 11/14/2019] [Accepted: 11/17/2019] [Indexed: 01/28/2023]
|
6
|
Hoge A, Guillaume M, Albert A, Tabart J, Dardenne N, Donneau AF, Kevers C, Defraigne JO, Pincemail J. Validation of a food frequency questionnaire assessing dietary polyphenol exposure using the method of triads. Free Radic Biol Med 2019; 130:189-195. [PMID: 30395973 DOI: 10.1016/j.freeradbiomed.2018.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 10/31/2018] [Accepted: 11/01/2018] [Indexed: 12/18/2022]
Abstract
When conducting research on polyphenols and their effects on health, it is of primary importance to use standardised and validated dietary assessment tools. This paper aims at assessing the validity of a food frequency questionnaire (FFQ) for quantifying dietary polyphenol exposure among healthy adults using the method of triads. Fifty-three healthy adults, aged 20-60, were included in the study. Total dietary polyphenol intake (TDP) estimated by the FFQ was compared with TDP measured by a 3-day food record (FR) and with urinary excretion levels of total polyphenols (TUP). Pearson correlations were calculated between methods. Validity coefficients (VC) were estimated between the three measurements and the 'unknown' true intake. There was a strong correlation between both dietary methods (r = 0.70, p < 0.0001). A moderate but significant association was observed between FFQ-derived TDP and TUP (r = 0.32, p = 0.020). The method of triads yielded a VC for the FFQ of 0.63 (95%CI: 0.41-0.84), indicating a strong relationship between FFQ-derived TDP and the true polyphenol intake. This study shows that the FFQ is an adequate tool not only for measuring dietary polyphenol exposure in nutrition epidemiological studies but also for guiding clinicians in dietary advice and counselling.
Collapse
Affiliation(s)
- Axelle Hoge
- Department of Public Health, University of Liège, Liège, Belgium.
| | | | - Adelin Albert
- Department of Public Health, University of Liège, Liège, Belgium
| | - Jessica Tabart
- Plant Molecular Biology and Biotechnology Unit, University of Liège, Liège, Belgium
| | - Nadia Dardenne
- Department of Public Health, University of Liège, Liège, Belgium
| | | | - Claire Kevers
- Plant Molecular Biology and Biotechnology Unit, University of Liège, Liège, Belgium
| | - Jean-Olivier Defraigne
- Department of Cardiovascular Surgery, University Hospital of Liège; Research Centre for Experimental Surgery (CREDEC), University of Liège, and Plateforme Nutrition Antioxydante & Santé (NAS), Liège, Belgium
| | - Joël Pincemail
- Department of Cardiovascular Surgery, University Hospital of Liège; Research Centre for Experimental Surgery (CREDEC), University of Liège, and Plateforme Nutrition Antioxydante & Santé (NAS), Liège, Belgium
| |
Collapse
|
7
|
da Silva DCG, Segheto W, de Lima MFC, Pessoa MC, Pelúzio MCG, Marchioni DML, Cunha DB, Longo GZ. Using the method of triads in the validation of a food frequency questionnaire to assess the consumption of fatty acids in adults. J Hum Nutr Diet 2017; 31:85-95. [DOI: 10.1111/jhn.12497] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- D. C. G. da Silva
- Department of Nutrition and Health; Federal University of Viçosa; Viçosa Brazil
| | - W. Segheto
- Department of Nutrition and Health; Federal University of Viçosa; Viçosa Brazil
| | - M. F. C. de Lima
- Department of Nutrition and Health; Federal University of Viçosa; Viçosa Brazil
| | - M. C. Pessoa
- Nursing Department; Federal University of Minas Gerais; Belo Horizonte Brazil
| | - M. C. G. Pelúzio
- Department of Nutrition and Health; Federal University of Viçosa; Viçosa Brazil
| | - D. M. L. Marchioni
- Nutrition Department; School of Public Health; University of São Paulo; São Paulo Brazil
| | - D. B. Cunha
- Department of Epidemiology; University of the State Rio de Janeiro; Rio de Janeiro Brazil
| | - G. Z. Longo
- Department of Nutrition and Health; Federal University of Viçosa; Viçosa Brazil
| |
Collapse
|
8
|
Almiron-Roig E, Aitken A, Galloway C, Ellahi B. Dietary assessment in minority ethnic groups: a systematic review of instruments for portion-size estimation in the United Kingdom. Nutr Rev 2017; 75:188-213. [PMID: 28340101 PMCID: PMC5410991 DOI: 10.1093/nutrit/nuw058] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Context Dietary assessment in minority ethnic groups is critical for surveillance programs and for implementing effective interventions. A major challenge is the accurate estimation of portion sizes for traditional foods and dishes. Objective The aim of this systematic review was to assess records published up to 2014 describing a portion-size estimation element (PSEE) applicable to the dietary assessment of UK-residing ethnic minorities. Data sources, selection, and extraction Electronic databases, internet sites, and theses repositories were searched, generating 5683 titles, from which 57 eligible full-text records were reviewed. Data analysis Forty-two publications about minority ethnic groups (n = 20) or autochthonous populations (n = 22) were included. The most common PSEEs (47%) were combination tools (eg, food models and portion-size lists), followed by portion-size lists in questionnaires/guides (19%) and image-based and volumetric tools (17% each). Only 17% of PSEEs had been validated against weighed data. Conclusions When developing ethnic-specific dietary assessment tools, it is important to consider customary portion sizes by sex and age, traditional household utensil usage, and population literacy levels. Combining multiple PSEEs may increase accuracy, but such methods require validation.
Collapse
Affiliation(s)
- Eva Almiron-Roig
- E. Almiron-Roig is with the MRC Elsie Widdowson Laboratory, Cambridge, United Kingdom, and the Centre for Nutrition Research, University of Navarra, Pamplona, Spain. C. Galloway was formerly with MRC Elsie Widdowson Laboratory, Cambridge, United Kingdom, and is presently with the Behaviour and Health Research Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, United Kingdom. A. Aitken and B. Ellahi are with the Faculty of Health and Social Care, University of Chester, Chester, United Kingdom
| | - Amanda Aitken
- E. Almiron-Roig is with the MRC Elsie Widdowson Laboratory, Cambridge, United Kingdom, and the Centre for Nutrition Research, University of Navarra, Pamplona, Spain. C. Galloway was formerly with MRC Elsie Widdowson Laboratory, Cambridge, United Kingdom, and is presently with the Behaviour and Health Research Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, United Kingdom. A. Aitken and B. Ellahi are with the Faculty of Health and Social Care, University of Chester, Chester, United Kingdom
| | - Catherine Galloway
- E. Almiron-Roig is with the MRC Elsie Widdowson Laboratory, Cambridge, United Kingdom, and the Centre for Nutrition Research, University of Navarra, Pamplona, Spain. C. Galloway was formerly with MRC Elsie Widdowson Laboratory, Cambridge, United Kingdom, and is presently with the Behaviour and Health Research Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, United Kingdom. A. Aitken and B. Ellahi are with the Faculty of Health and Social Care, University of Chester, Chester, United Kingdom
| | - Basma Ellahi
- E. Almiron-Roig is with the MRC Elsie Widdowson Laboratory, Cambridge, United Kingdom, and the Centre for Nutrition Research, University of Navarra, Pamplona, Spain. C. Galloway was formerly with MRC Elsie Widdowson Laboratory, Cambridge, United Kingdom, and is presently with the Behaviour and Health Research Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, United Kingdom. A. Aitken and B. Ellahi are with the Faculty of Health and Social Care, University of Chester, Chester, United Kingdom
| |
Collapse
|
9
|
Palma-Duran SA, Caire-Juvera G, Robles-Burgeño MDR, Ortega-Vélez MI, Gutiérrez-Coronado MDL, Bermúdez Almada MDC, Chávez-Suárez K, Campa-Siqueiros M, Grajeda-Cota P, Saucedo-Tamayo MDS, Valenzuela-Quintanar AI. Serum levels of phytoestrogens as biomarkers of intake in Mexican women. Int J Food Sci Nutr 2015; 66:819-25. [DOI: 10.3109/09637486.2015.1092019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
10
|
Parry B. Nutrition and Breast Cancer. Nutr Cancer 2013. [DOI: 10.1002/9781118788707.ch17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
11
|
Garduño-Diaz SD, Husain W, Ashkanani F, Khokhar S. Meeting challenges related to the dietary assessment of ethnic minority populations. J Hum Nutr Diet 2013; 27:358-66. [PMID: 24033680 DOI: 10.1111/jhn.12153] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND Migrants from the Indian subcontinent comprise the largest minority group in the UK. With the process of migration come alterations in lifestyle and eating habits. The present study aimed to disseminate the valuable information, experiences and challenges faced by researchers who conduct studies with ethnic minority groups in the area of diet and nutritional surveys, with an emphasis on migrant South Asians. METHODS The findings reported are the result of research carried out during 2008-2012, involving 1100 face-to-face dietary recalls conducted in the UK among South Asian children (aged 1.5-11 years; n = 300) and adults (≥30 years; n = 100). RESULTS Factors to consider when planning and carrying out diet and nutrition survey studies among migrant South Asians were identified and include the employment of culture-specific tools, visual aid reinforcement and the involvement of key community members and translators to facilitate recruitment and data collection. One of the best practices found when working with minority groups was the use of incentives and tangible benefits to reward study participants. It was also found that constant communication and follow-up of the study participants improved the quality of the data and the likelihood of maintaining links with community members for future studies. CONCLUSIONS From the results of in-house studies and a revision of practices reported in earlier literature, two 24-h face-to-face dietary recalls are recommended as the optimal method for the dietary assessment of migrant South Asians. To complement this assessment, ethnic-specific food frequency questionnaires such as that developed and successfully implemented among South Asians in the present study must be employed.
Collapse
Affiliation(s)
- S D Garduño-Diaz
- Department of General Education, American University of the Middle East, Egaila, Kuwait
| | | | | | | |
Collapse
|
12
|
Fernandez AR, Omar SZ, Husain R. Development and validation of a food frequency questionnaire to estimate the intake of genistein in Malaysia. Int J Food Sci Nutr 2013; 64:794-800. [DOI: 10.3109/09637486.2013.798269] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
13
|
Hernandez-Elizondo J, Monteagudo C, Murcia MA, Olea N, Olea-Serrano F, Mariscal-Arcas M. Assessment of the estrogenicity of the diet of a healthy female Spanish population based on its isoflavone content. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2013; 30:627-33. [PMID: 23506255 DOI: 10.1080/19440049.2013.775604] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Phytoestrogens are natural components of plants consumed by humans. The hormonal activity of these substances has long been known. Various in vitro tests have demonstrated the agonistic or antagonistic estrogenic activity of some phytoestrogens. The objective of this study was to estimate the supply of isoflavones in the diet of a healthy adult female population and to assess its estrogenic effect. The diet was assessed by questionnaire and the estrogenicity of the estimated isoflavone content was tested by E-screen, finding a mean total estrogenic capacity of 0.129 × 10⁻¹⁰ eq.E₂ (12.9 pmol day⁻¹), corresponding to a daily isoflavone intake of 265.8 μg day⁻¹. This study offers a preliminary insight into the phytoestrogen content of the diet of a healthy active population of Spanish women. The effects of this additional hormonal burden are highly controversial, and this approach to estimating dietary phytoestrogen intake of specific populations may help to elucidate its implications for human health.
Collapse
Affiliation(s)
- J Hernandez-Elizondo
- Research Group on Nutrition, Diet and Risk Assessment-AGR255, Department of Nutrition and Food Science, University of Granada, Granada, Spain
| | | | | | | | | | | |
Collapse
|
14
|
Development of a food compositional database for the estimation of dietary intake of phyto-oestrogens in a group of postmenopausal women previously treated for breast cancer and validation with urinary excretion. Br J Nutr 2013; 109:2261-8. [DOI: 10.1017/s0007114512004394] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The scientific literature contains evidence suggesting that women who have been treated for breast cancer may, as a result of their diagnosis, increase their phyto-oestrogen (PE) intake. In the present paper, we describe the creation of a dietary analysis database (based on Dietplan6) for the determination of dietary intakes of specific PE (daidzein, genistein, glycitein, formononetin, biochanin A, coumestrol, matairesinol and secoisolariciresinol), in a group of women previously diagnosed and treated for postmenopausal breast cancer. The design of the database, data evaluation criteria, literature data entry for 551 foods and primary analysis by LC–MS/MS of an additional thirty-four foods for which there were no published data are described. The dietary intake of 316 women previously treated for postmenopausal breast cancer informed the identification of potential food and beverage sources of PE and the bespoke dietary analysis database was created to, ultimately, quantify their PE intake. In order that PE exposure could be comprehensively described, fifty-four of the 316 subjects completed a 24 h urine collection, and their urinary excretion results allowed for the description of exposure to include those identified as ‘equol producers’.
Collapse
|
15
|
Validation of FFQ-based assessment of dietary lignans compared with serum enterolactone in Swedish women. Br J Nutr 2012; 109:1873-80. [PMID: 23006454 DOI: 10.1017/s000711451200387x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The validity of using FFQ to assess dietary lignans is uncertain. We aimed to validate the use of FFQ for the assessment of dietary intake of lignans compared to the serum biomarker enterolactone, the main product of dietary lignans' metabolism in human subjects. A random sample of women, aged 55–75 years, from the Swedish Mammography Cohort was selected. Information from two FFQ, the FFQ-87 (sixty-seven food items) and the FFQ-97 (ninety-three food items), and blood samples were collected. Dietary intake of lignans (secoisolariciresinol, matairesinol, lariciresinol, pinoresinol, medioresinol and syringaresinol) was assessed by the FFQ. Serum concentrations of enterolactone were analysed by time-resolved fluoroimmunoassay. The correlation coefficient between energy-adjusted lignan intake and serum enterolactone was estimated in crude and multivariable-adjusted models, taking into account the factors potentially influencing the serum enterolactone. Among the 135 participants aged 55–75 years, with a mean BMI of 26·7 kg/m2, the average energy-adjusted intake of total lignans was 1616 (sd 424) and 1516 (sd 409) μg/d according to the FFQ-87 (forty-five food items containing lignans) and the FFQ-97 (sixty-five food items containing lignans), respectively. The mean concentration of serum enterolactone was 23·2 (sd 15·4) nmol/l. The adjusted Pearson's correlation between dietary intake of lignans assessed by the FFQ-97 and serum enterolactone was statistically significant (r 0·22, P= 0·01). No significant correlation was observed for the FFQ-87 (r 0·09, P= 0·30). The present study indicates that the FFQ-97 might be better than the FFQ-87 for assessing dietary intake of lignans, although the correlation was low.
Collapse
|
16
|
Vanaelst B, Huybrechts I, Bammann K, Michels N, de Vriendt T, Vyncke K, Sioen I, Iacoviello L, Günther K, Molnar D, Lissner L, Rivet N, Raul JS, de Henauw S. Intercorrelations between serum, salivary, and hair cortisol and child-reported estimates of stress in elementary school girls. Psychophysiology 2012; 49:1072-81. [PMID: 22725679 DOI: 10.1111/j.1469-8986.2012.01396.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 04/26/2012] [Indexed: 11/27/2022]
Abstract
To evaluate the impact of stress on children's well-being, it is important to have valid and reliable stress assessment methods. Nevertheless, selection of an appropriate method for a particular research question may not be straightforward, as there is currently no consensus on a reference method to measure stress in children. This article examined to what extent childhood stress can be estimated accurately by stressor questionnaires (i.e., Coddington life events scale) and biological markers (serum, salivary, and hair cortisol) using the Triads (a triangulation) method in 272 elementary school girls. Salivary cortisol was shown to most accurately indicate true childhood stress for short periods in the past (i.e., last 3 months), whereas hair cortisol may be preferred above salivary measurements for periods more distant and thus for chronic stress assessment. However, applicability should be confirmed in larger and more heterogeneous populations.
Collapse
|
17
|
Slater B, Enes CC, López RVM, Damasceno NRT, Voci SM. Validation of a food frequency questionnaire to assess the consumption of carotenoids, fruits and vegetables among adolescents: the method of triads. CAD SAUDE PUBLICA 2011; 26:2090-100. [PMID: 21180982 DOI: 10.1590/s0102-311x2010001100010] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Accepted: 03/01/2010] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to validate the intake of carotenoids, fruits and vegetables estimated by the Food Frequency Questionnaire for Adolescents (FFQA) using the method of triads. Blood samples were collected from 80 elementary school adolescents to assess serum levels of β-carotene. Partial correlation coefficients (r) were calculated between an estimated intake of carotenoids, fruits and vegetables and the serum levels of β-carotene. Validity coefficients were calculated using the method of triads. With the exception of carotenoids, partial r from the food frequency questionnaire (FFQ) were greater than those of the 24-hour recall (24hR). The fruit/vegetable group showed the highest partial r for the FFQ (r = 0.235) and the 24hR (r = 0.137). The highest validity coefficient was obtained for the vegetable group, as assessed by the FFQ (r = 0.873). On average, the validity coefficient values for the FFQ were greater than those obtained for the 24hR or the β-carotene serum levels. The FFQA is an accurate tool for estimating the intake of carotenoids, fruits and vegetables in this population group.
Collapse
|
18
|
Peterson J, Dwyer J, Adlercreutz H, Scalbert A, Jacques P, McCullough ML. Dietary lignans: physiology and potential for cardiovascular disease risk reduction. Nutr Rev 2010; 68:571-603. [PMID: 20883417 DOI: 10.1111/j.1753-4887.2010.00319.x] [Citation(s) in RCA: 220] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The present review of the literature on lignan physiology and lignan intervention and epidemiological studies was conducted to determine if lignans decrease the risks of cardiovascular disease in Western populations. Five intervention studies using flaxseed lignan supplements indicated beneficial associations with C-reactive protein, and a meta-analysis that included these studies also suggested lignans have a lowering effect on plasma total and low-density lipoprotein cholesterol. Three intervention studies using sesamin supplements indicated possible lipid- and blood pressure-lowering associations. Eleven human observational epidemiological studies examined dietary intakes of lignans in relation to cardiovascular disease risk. Five showed decreased risk with either increasing dietary intakes of lignans or increased levels of serum enterolactone (an enterolignan used as a biomarker of lignan intake), five studies were of borderline significance, and one was null. The associations between lignans and decreased risk of cardiovascular disease are promising, but they are yet not well established, perhaps due to low lignan intakes in habitual Western diets. At the higher doses used in intervention studies, associations were more evident.
Collapse
Affiliation(s)
- Julia Peterson
- Jean Mayer United States Department of Agriculture Human Nutrition Research Center on Aging and Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachussets, USA
| | | | | | | | | | | |
Collapse
|
19
|
Yokota RTDC, Miyazaki ES, Ito MK. Applying the triads method in the validation of dietary intake using biomarkers. CAD SAUDE PUBLICA 2010; 26:2027-37. [DOI: 10.1590/s0102-311x2010001100004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Accepted: 06/16/2010] [Indexed: 11/22/2022] Open
Abstract
The triads method is applied in validation studies of dietary intake to evaluate the correlation between three measurements (food frequency questionnaire, reference method and biomarker) and the true intake using validity coefficients (Á). The main advantage of this technique is the inclusion of the biomarker, which presents independent errors compared with those of the traditional methods. The method assumes the linearity between the three measurements and the true intake and independence between the three measurement errors. Limitations of this technique include the occurrence of Á > 1, known as "Heywood case", and the existence of negative correlations, which do not allow the calculation of Á. The objective of this review is to present the concept of the method, describe its application and examine the validation studies of dietary intake that use the triads method. We also conceptualize the "bootstrap" method, used to estimate the confidence intervals of the validity coefficients.
Collapse
|
20
|
Tseng M, Olufade T, Kurzer MS, Wahala K, Fang CY, van der Schouw YT, Daly MB. Food frequency questionnaires and overnight urines are valid indicators of daidzein and genistein intake in U.S. women relative to multiple 24-h urine samples. Nutr Cancer 2009; 60:619-26. [PMID: 18791925 DOI: 10.1080/01635580801993751] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Data regarding convenient, valid methods for measuring U.S. isoflavone intake are limited. We evaluated a soy food questionnaire (SFQ), the Willett food frequency questionnaire (FFQ), and overnight urine samples relative to excretion in 24-h urine samples. We also described intake among women in a high-risk program for breast or ovarian cancer. Between April 2002 and June 2003, 451 women aged 30 to 50 yr with a family history of breast or ovarian cancer completed the SFQ and FFQ. Of them, 27 provided four 24-h and overnight urine specimens. In these women, 24-h sample measures were correlated with SFQ estimates of daidzein (Spearman r = .48) and genistein (r = .54) intake, moderately correlated with the Willett FFQ (daidzein r = .38, genistein r = .33), and strongly correlated with overnight urine excretion (daidzein r = .84, genistein r = 0.93). Among all 451 SFQ respondents, mean (median) daidzein and genistein intakes were 2.8 (0.24) and 3.9 (0.30) mg/day. Primary sources of both were soymilk, soy nuts, and tofu. We conclude that targeted soy food questionnaires, comprehensive FFQs, and multiple overnight urines are all reasonable options for assessing isoflavone intake in epidemiologic studies.
Collapse
Affiliation(s)
- Marilyn Tseng
- Division of Population Science, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19130, USA.
| | | | | | | | | | | | | |
Collapse
|
21
|
Landberg R, Kamal-Eldin A, Andersson A, Vessby B, Aman P. Alkylresorcinols as biomarkers of whole-grain wheat and rye intake: plasma concentration and intake estimated from dietary records. Am J Clin Nutr 2008; 87:832-8. [PMID: 18400704 DOI: 10.1093/ajcn/87.4.832] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Alkylresorcinols (ARs), phenolic lipids exclusively present in the outer parts of wheat and rye grains, have been proposed as specific dietary biomarkers of whole-grain wheat and rye intake. OBJECTIVE The objective was to validate plasma ARs as a biomarker of whole-grain wheat and rye intakes by studying the correlation between their plasma concentration and intake calculated from food records. DESIGN In a randomized crossover study, 22 women and 8 men were given a defined amount of either whole-grain or refined-cereal-grain products to be included in their habitual diets for two 6-wk periods. Blood samples were collected and food intakes were recorded before and after each intervention period. RESULTS Plasma AR concentrations were significantly higher after the whole-grain diet period than after the refined-grain period (P < 0.0001) and were well correlated with average daily AR intake estimated by self-reported weighed food records (Spearman's r = 0.58, P < 0.001). CONCLUSION Plasma AR concentrations are correlated with intake assessed by food records, which suggests that ARs are selective nutritional biomarkers for the intake of whole-grain wheat and rye.
Collapse
Affiliation(s)
- Rikard Landberg
- Department of Food Science, Swedish University of Agriculture Science, Uppsala, Sweden.
| | | | | | | | | |
Collapse
|
22
|
Milder IEJ, Kuijsten A, Arts ICW, Feskens EJM, Kampman E, Hollman PCH, Van 't Veer P. Relation between plasma enterodiol and enterolactone and dietary intake of lignans in a Dutch endoscopy-based population. J Nutr 2007; 137:1266-71. [PMID: 17449591 DOI: 10.1093/jn/137.5.1266] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Enterolignans are phytoestrogenic compounds derived from the conversion of dietary lignans by the intestinal microflora that may be protective against cardiovascular diseases and cancer. To evaluate the use of enterolignans as biomarkers of dietary lignan intake, we studied the relation between plasma and dietary lignans. We determined the dietary intake of 4 lignans (secoisolariciresinol (SECO), matairesinol (MAT), pinoresinol, and lariciresinol) using the European Prospective Investigation into Cancer and Nutrition FFQ, and plasma enterodiol (END) and enterolactone (ENL) concentrations were determined by liquid chromatography-tandem mass spectrometry. The population consisted of 637 men and women, aged 19-75 y, participating in a case-control study on colorectal adenomas. Participants did not use antibiotics in the preceding calendar year. We found a modest association between lignan intake and plasma END (Spearman r = 0.09, P = 0.03) and ENL (Spearman r = 0.18, P <0.001). The correlation of total lignan intake with plasma enterolignans was slightly stronger than that of only SECO plus MAT. The plasma concentrations of both END and ENL were associated with intake of dietary fiber and vegetable protein but not with intake of other macronutrients. The relation between lignan intake and plasma END was modulated by age and previous use of antibiotics, whereas for ENL, it was modulated by weight, current smoking, and frequency of defecation. However, even when we included these nondietary factors in the regression models, the explained variance in plasma END and ENL remained low (2 and 13%, respectively).
Collapse
Affiliation(s)
- Ivon E J Milder
- Centre for Nutrition and Health, National Institute of Public Health and the Environment, 3720 BA Bilthoven, The Netherlands.
| | | | | | | | | | | | | |
Collapse
|
23
|
McNaughton SA, Hughes MC, Marks GC. Validation of a FFQ to estimate the intake of PUFA using plasma phospholipid fatty acids and weighed foods records. Br J Nutr 2007; 97:561-8. [PMID: 17313719 DOI: 10.1017/s0007114507381385] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Due to the growing knowledge about the role of specific fatty acids in health and disease, dietary intake measurements of individual fatty acids or classes of fatty acids are becoming increasingly important. The objective of this study was to evaluate the ability of the Nambour FFQ to estimate intakes of specific fatty acids, particularly PUFA. The study population was a sub-sample of adult participants in a randomised controlled trial of beta-carotene and sunscreen in the prevention of skin cancer (n 43). Dietary intake was assessed by a self-administered FFQ and a weighed food record (WFR). Non-fasting blood samples were collected and analysed for plasma phospholipid fatty acids. Median intakes on the FFQ were generally higher than the WFR except for the n-3 PUFA groups, where the FFQ estimated higher intakes. Correlations between the FFQ and WFR were moderate (r 0 x 32-0 x 59) except for trans fatty acids (r 0 x 03). Correlations between each of the dietary assessment methods and the plasma phospholipids were poor for all fatty acids other than the PUFA. Using the methods of triads approach, the FFQ validity coefficients for total n-3 fatty acids, total long chain n-3 fatty acids, EPA, arachidonic acid, docosapentaenoic acid and DHA were 0 x 50, 0 x 63, 0 x 45 and 0 x 62 and 0 x 62, respectively. For most fatty acids, the FFQ adequately estimates group mean fatty acid intakes and can adequately rank individuals; however, the ability of this FFQ to estimate trans fatty acids was poor.
Collapse
Affiliation(s)
- S A McNaughton
- School of Population Health, University of Queensland, Herston, Australia.
| | | | | |
Collapse
|
24
|
Bhakta D, Higgins CD, Sevak L, Mangtani P, Adlercreutz H, McMichael AJ, dos Santos Silva I. Phyto-oestrogen intake and plasma concentrations in South Asian and native British women resident in England. Br J Nutr 2007; 95:1150-8. [PMID: 16768838 DOI: 10.1079/bjn20061777] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Phyto-oestrogens, naturally occurring hormone-like chemicals in plant food, may play a protective role against hormone-related chronic diseases. South Asian migrants in the UK have a lower incidence of hormone-related cancer than their hosts but the extent to which this difference may be due to phytoestrogen intake is not known. The aim was to compare habitual phytoestrogen intake in first-generation South Asian migrant women and native British women. South Asian (n 221) and native British women (n 50) were recruited from general practitioner lists and were asked to provide monthly 24h recalls for a period of 1 year. An enhanced phytoestrogen database was compiled using data from a literature search and unpublished data. A sub-sample of South Asian women (n 100) and the native British women (n 40) also provided blood samples every 3 months during the 1-year period. The median daily intakes (μg/d) of isoflavones (184·2 v. 333·9) and lignans (110·8 v. 148·8) were significantly lower in South Asians than in the native British (P<0·001, P=0·04 respectively).There were no significant differences in mean plasma isoflavone levels (nmol/l) but plasma enterolactone was significantly lower in the South Asians (13·9 (sd17·5) v. 28·5 (SD23·3),P<0·001). The main sources of phytoestrogens were bread and vegetables in both ethnic groups. Habitual phytoestrogen intake in South Asian and native British women was below 1mg/d and was higher in the native British diet. The present study does not support the hypothesis that differences in phytoestrogen intake, or in circulating levels, could explain differences in hormone-related cancer risks between these two populations.
Collapse
Affiliation(s)
- Dee Bhakta
- Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | | | | | | | | | | | | |
Collapse
|
25
|
French MR, Thompson LU, Hawker GA. Validation of a phytoestrogen food frequency questionnaire with urinary concentrations of isoflavones and lignan metabolites in premenopausal women. J Am Coll Nutr 2007; 26:76-82. [PMID: 17353586 DOI: 10.1080/07315724.2007.10719588] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE The purpose of this study was to examine the association between dietary intake of phytoestrogens estimated by a food frequency questionnaire (FFQ) with urinary metabolites. METHODS Participants were 26 premenopausal, Caucasian women aged 25 to 42 years. Dietary intake of isoflavones (genistein and daidzein) and lignans (secoisolariciresinol and matairesinol) were estimated by a 53-item interviewer-administered FFQ on two occasions, reflecting 'habitual' (previous 2 months) and 'recent' (previous 2 days) dietary intake. Isoflavone (genistein, daidzein) and lignan (enterolactone, enterodiol and secoisolariciresinol) concentrations were measured in 24-hour urine samples by gas chromatography-mass spectrometry. Correlations between FFQ (habitual and recent, separately) and urinary metabolite values were assessed using Spearman correlation coefficients. RESULTS Mean habitual isoflavone and lignan intakes were 13.7 mg/day and 13.8 mg/day, respectively. Mean urinary concentrations of isoflavones and lignans were 17.4 micromol/day and 20.6 micromol/day, respectively. Recent and habitual isoflavone intakes were correlated with urinary excretion of metabolites (r = 0.64, p < 0.001 and r = 0.54, p = 0.004, respectively). Urinary excretion of lignans was also modestly correlated with recent and habitual lignan intakes (r = 0.46, p = 0.02 and r = 0.40, p = 0.05, respectively). CONCLUSIONS Our results support the use of this FFQ as a measure of dietary isoflavone and lignan intake in epidemiological studies.
Collapse
Affiliation(s)
- Melissa R French
- Osteoporosis Research Program, Women's College Hospital, 76 Grenville Street, Toronto, Ontario M5S 1B2, CANADA
| | | | | |
Collapse
|