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Am J Epidemiol ; 188(10): 1858-1867, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31318012


The Oxford WebQ is an online 24-hour dietary questionnaire that is appropriate for repeated administration in large-scale prospective studies, including the UK Biobank study and the Million Women Study. We compared the performance of the Oxford WebQ and a traditional interviewer-administered multiple-pass 24-hour dietary recall against biomarkers for protein, potassium, and total sugar intake and total energy expenditure estimated by accelerometry. We recruited 160 participants in London, United Kingdom, between 2014 and 2016 and measured their biomarker levels at 3 nonconsecutive time points. The measurement error model simultaneously compared all 3 methods. Attenuation factors for protein, potassium, total sugar, and total energy intakes estimated as the mean of 2 applications of the Oxford WebQ were 0.37, 0.42, 0.45, and 0.31, respectively, with performance improving incrementally for the mean of more measures. Correlation between the mean value from 2 Oxford WebQs and estimated true intakes, reflecting attenuation when intake is categorized or ranked, was 0.47, 0.39, 0.40, and 0.38, respectively, also improving with repeated administration. These correlations were similar to those of the more administratively burdensome interviewer-based recall. Using objective biomarkers as the standard, the Oxford WebQ performs well across key nutrients in comparison with more administratively burdensome interviewer-based 24-hour recalls. Attenuation improves when the average value is taken over repeated administrations, reducing measurement error bias in assessment of diet-disease associations.

Inquéritos sobre Dietas/métodos , Acelerometria , Adulto , Biomarcadores/sangue , Biomarcadores/urina , Proteínas Sanguíneas/análise , Dióxido de Carbono/metabolismo , Dieta/estatística & dados numéricos , Carboidratos da Dieta/administração & dosagem , Ingestão de Energia , Metabolismo Energético , Feminino , Humanos , Entrevistas como Assunto , Londres , Masculino , Rememoração Mental , Sistemas On-Line , Consumo de Oxigênio , Potássio/sangue , Reprodutibilidade dos Testes , Inquéritos e Questionários
BMC Med ; 16(1): 136, 2018 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-30089491


BACKGROUND: Online dietary assessment tools can reduce administrative costs and facilitate repeated dietary assessment during follow-up in large-scale studies. However, information on bias due to measurement error of such tools is limited. We developed an online 24-h recall (myfood24) and compared its performance with a traditional interviewer-administered multiple-pass 24-h recall, assessing both against biomarkers. METHODS: Metabolically stable adults were recruited and completed the new online dietary recall, an interviewer-based multiple pass recall and a suite of reference measures. Longer-term dietary intake was estimated from up to 3 × 24-h recalls taken 2 weeks apart. Estimated intakes of protein, potassium and sodium were compared with urinary biomarker concentrations. Estimated total sugar intake was compared with a predictive biomarker and estimated energy intake compared with energy expenditure measured by accelerometry and calorimetry. Nutrient intakes were also compared to those derived from an interviewer-administered multiple-pass 24-h recall. RESULTS: Biomarker samples were received from 212 participants on at least one occasion. Both self-reported dietary assessment tools led to attenuation compared to biomarkers. The online tools resulted in attenuation factors of around 0.2-0.3 and partial correlation coefficients, reflecting ranking intakes, of approximately 0.3-0.4. This was broadly similar to the more administratively burdensome interviewer-based tool. Other nutrient estimates derived from myfood24 were around 10-20% lower than those from the interviewer-based tool, with wide limits of agreement. Intraclass correlation coefficients were approximately 0.4-0.5, indicating consistent moderate agreement. CONCLUSIONS: Our findings show that, whilst results from both measures of self-reported diet are attenuated compared to biomarker measures, the myfood24 online 24-h recall is comparable to the more time-consuming and costly interviewer-based 24-h recall across a range of measures.

Biomarcadores/química , Técnicas e Procedimentos Diagnósticos/estatística & dados numéricos , Dieta/métodos , Avaliação Nutricional , Adolescente , Adulto , Idoso , Educação a Distância , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Projetos de Pesquisa , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
PLoS One ; 12(7): e0182195, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28750055


Ever more evidence associates short sleep with increased risk of metabolic diseases such as obesity, which may be related to a predisposition to non-homeostatic eating. Few studies have concurrently determined associations between sleep duration and objective measures of metabolic health as well as sleep duration and diet, however. We therefore analyzed associations between sleep duration, diet and metabolic health markers in UK adults, assessing associations between sleep duration and 1) adiposity, 2) selected metabolic health markers and 3) diet, using National Diet and Nutrition Survey data. Adults (n = 1,615, age 19-65 years, 57.1% female) completed questions about sleep duration and 3 to 4 days of food diaries. Blood pressure and waist circumference were recorded. Fasting blood lipids, glucose, glycated haemoglobin (HbA1c), thyroid hormones, and high-sensitivity C-reactive protein (CRP) were measured in a subset of participants. We used regression analyses to explore associations between sleep duration and outcomes. After adjustment for age, ethnicity, sex, smoking, and socioeconomic status, sleep duration was negatively associated with body mass index (-0.46 kg/m2 per hour, 95% CI -0.69 to -0.24 kg/m2, p < 0.001) and waist circumference (-0.9 cm per hour, 95% CI -1.5 to -0.3cm, p = 0.004), and positively associated with high-density lipoprotein cholesterol (0.03 mmol/L per hour, 95% CI 0.00 to 0.05, p = 0.03). Sleep duration tended to be positively associated with free thyroxine levels and negatively associated with HbA1c and CRP (p = 0.09 to 0.10). Contrary to our hypothesis, sleep duration was not associated with any dietary measures (p ≥ 0.14). Together, our findings show that short-sleeping UK adults are more likely to have obesity, a disease with many comorbidities.

Índice de Massa Corporal , Dieta , Metabolômica , Inquéritos Nutricionais , Sono/fisiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Saúde , Humanos , Lactente , Masculino , Reino Unido/epidemiologia , Circunferência da Cintura , Adulto Jovem
Endocr Rev ; 37(6): 584-608, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27763782


Circadian (∼24-hour) timing systems pervade all kingdoms of life and temporally optimize behavior and physiology in humans. Relatively recent changes to our environments, such as the introduction of artificial lighting, can disorganize the circadian system, from the level of the molecular clocks that regulate the timing of cellular activities to the level of synchronization between our daily cycles of behavior and the solar day. Sleep/wake cycles are intertwined with the circadian system, and global trends indicate that these, too, are increasingly subject to disruption. A large proportion of the world's population is at increased risk of environmentally driven circadian rhythm and sleep disruption, and a minority of individuals are also genetically predisposed to circadian misalignment and sleep disorders. The consequences of disruption to the circadian system and sleep are profound and include myriad metabolic ramifications, some of which may be compounded by adverse effects on dietary choices. If not addressed, the deleterious effects of such disruption will continue to cause widespread health problems; therefore, implementation of the numerous behavioral and pharmaceutical interventions that can help restore circadian system alignment and enhance sleep will be important.

Fenômenos Cronobiológicos/fisiologia , Privação do Sono , Transtornos do Sono do Ritmo Circadiano , Fenômenos Cronobiológicos/genética , Humanos , Privação do Sono/etiologia , Privação do Sono/genética , Privação do Sono/metabolismo , Privação do Sono/terapia , Transtornos do Sono do Ritmo Circadiano/etiologia , Transtornos do Sono do Ritmo Circadiano/genética , Transtornos do Sono do Ritmo Circadiano/metabolismo , Transtornos do Sono do Ritmo Circadiano/terapia
Br J Nutr ; 116(3): 434-42, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27221157


The human circadian system anticipates and adapts to daily environmental changes to optimise behaviour according to time of day and temporally partitions incompatible physiological processes. At the helm of this system is a master clock in the suprachiasmatic nuclei (SCN) of the anterior hypothalamus. The SCN are primarily synchronised to the 24-h day by the light/dark cycle; however, feeding/fasting cycles are the primary time cues for clocks in peripheral tissues. Aligning feeding/fasting cycles with clock-regulated metabolic changes optimises metabolism, and studies of other animals suggest that feeding at inappropriate times disrupts circadian system organisation, and thereby contributes to adverse metabolic consequences and chronic disease development. 'High-fat diets' (HFD) produce particularly deleterious effects on circadian system organisation in rodents by blunting feeding/fasting cycles. Time-of-day-restricted feeding, where food availability is restricted to a period of several hours, offsets many adverse consequences of HFD in these animals; however, further evidence is required to assess whether the same is true in humans. Several nutritional compounds have robust effects on the circadian system. Caffeine, for example, can speed synchronisation to new time zones after jetlag. An appreciation of the circadian system has many implications for nutritional science and may ultimately help reduce the burden of chronic diseases.

Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Comportamento Alimentar , Fenômenos Fisiológicos da Nutrição , Estado Nutricional/fisiologia , Obesidade/etiologia , Animais , Dieta Hiperlipídica/efeitos adversos , Humanos , Obesidade/fisiopatologia