Dietary intake measurement using 7 d diet diaries in British men and women in the European Prospective Investigation into Cancer-Norfolk study: a focus on methodological issues

Abstract

The aim of the present study was to describe the energy, nutrient and crude v. disaggregated food intake measured using 7 d diet diaries (7dDD) for the full baseline Norfolk cohort recruited for the European Prospective Investigation into Cancer (EPIC-Norfolk) study, with emphasis on methodological issues. The first data collection took place between 1993 and 1998 in Norfolk, East Anglia (UK). Of the 30 445 men and women, aged 40-79 years, registered with a general practitioner invited to participate in the study, 25 639 came for a health examination and were asked to complete a 7dDD. Data from diaries with data recorded for at least 1 d were obtained for 99 % members of the cohort; 10 354 (89·8 %) of the men and 12 779 (91·5 %) of the women completed the diet diaries for all 7 d. Mean energy intake (EI) was 9·44 (SD 2·22) MJ/d and 7·15 (SD 1·66) MJ/d, respectively. EI remained approximately stable across the days, but there was apparent under-reporting among the participants, especially among those with BMI . 25 kg/m 2 . Micronutrient density was higher among women than among men. In conclusion, under-reporting is an issue, but not more so than that found in national surveys. How foods were grouped (crude or disaggregated) made a difference to the estimates obtained, and comparison of intakes showed wide limits of agreement. The choice of variables influences estimates obtained from the food group data; while this may not alter the ranking of individuals within studies, this issue may be relevant when comparing absolute food intakes between studies.

Dietary magnesium and potassium intakes and circulating magnesium are associated with heel bone ultrasound attenuation and osteoporotic fracture risk in the EPIC-Norfolk cohort study ,

“…Detail of the Data Into Nutrients for Epidemiologic Research software used to record and translate the dietary information provided by the 7-d food diaries into nutrient quantities is reported elsewhere (26). All data entries were checked by nutritionists trained in use of the system (27).…”

A pilot study to determine whether using a lightweight, wearable micro-camera improves dietary assessment accuracy and offers information on macronutrients and eating rate

“…Propensity towards under-reporting using food records is far higher in obese compared with lean individuals (8)(9)(10)(11) (19 and 2 %, respectively (8) ). Furthermore, evidence of weight loss during study periods indicates under-eating.…”

“…Common techniques mainly include self-reported questionnaires and dietary records, which are subjective and known to have varying degrees of accuracy, and for this reason some have argued that all memory-based techniques should not be used in nutrition research and that objective measures should be developed in their place (1,2) . Estimates from a sample of adults aged 19-65 years participating in the 2000 UK National Diet and Nutrition Survey suggest that under-reporting occurs in up to 88 % of the sample depending on the method used to calculate underreporting and the various sub-samples examined (3) .Studies using the gold standard method of doubly labelled water (DLW) to measure energy expenditure (and, on the principle of energy balance, energy intake) have demonstrated under-reporting rates of between 2 and 59 % depending on the method of dietary assessment and population sample being studied (4)(5)(6)(7) .Propensity towards under-reporting using food records is far higher in obese compared with lean individuals (8)(9)(10)(11) (19 and 2 %, respectively (8) ). Furthermore, evidence of weight loss during study periods indicates under-eating.…”

Improving the estimation of flavonoid intake for study of health outcomes

“…41 Both of these studies used a single 24-hour recall, which may be too short in duration to reflect usual diets and may have captured unrepresentative (outlier) days that do not reflect usual diets. 61 Four studies 35,40,44,45 provided means and medians for many of the flavonoid classes, and 3 of these provided mean and median total flavonoid intakes. The median total intakes in these 3 studies were 44 mg/d, 57 mg/d, and 66 mg/d, lower than the means reported, illustrating that estimates tend to be skewed to the right (Table S1).…”

“…Inadequate dietary assessment tools also contribute to misestimation in exposure assessment. 61,95,[241][242][243][244][245][246][247][248][249] In most epidemiologic studies, very large numbers of participants (often tens of thousands) report their usual diets using semiquantitative food frequency questionnaires that maximize information while reducing both participant burden and the costs of coding and analysis. Even so, food frequency questionnaires are particularly challenging for the assessment of flavonoid intakes.…”