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

Abstract

A major limitation in nutritional science is the lack of understanding of the nutritional intake of free-living people. There is an inverse relationship between accuracy of reporting of energy intake by all current nutritional methodologies and body weight. In this pilot study we aim to explore whether using a novel lightweight, wearable micro-camera improves the accuracy of dietary intake assessment. Doubly labelled water (DLW) was used to estimate energy expenditure and intake over a 14-d period, over which time participants (n 6) completed a food diary and wore a micro-camera on 2 of the days. Comparisons were made between the estimated energy intake from the reported food diary alone and together with the images from the micro-camera recordings. There was an average daily deficit of 3912 kJ using food diaries to estimate energy intake compared with estimated energy expenditure from DLW (P = 0·0118), representing an under-reporting rate of 34 %. Analysis of food diaries alone showed a significant deficit in estimated daily energy intake compared with estimated intake from food diary analysis with images from the micro-camera recordings (405 kJ). Use of the micro-camera images in conjunction with food diaries improves the accuracy of dietary assessment and provides valuable information on macronutrient intake and eating rate. There is a need to develop this recording technique to remove user and assessor bias.Key words: Dietary recording: Doubly labelled water: Micro-camera devices: Energy intake A common weakness of nutritional research is not being able to accurately assess the dietary intake of people in their home environments. To understand the impact of nutritional health in the population there is a need to understand and measure energy expenditure and intake accurately. 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. This under-eating, along with the under-reporting observed in multiple studies, f...

Usefulness of Wearable Cameras as a Tool to Enhance Chronic Disease Self-Management: Scoping Review (Preprint)

“…Studies including data analysis were predominantly feasibility or pilot studies (n = 13, 54%) [9][10][11]16,20,[22][23][24][25][26][27][28][29], followed by validation studies (n = 4, 17%) [8,28,30,31] and methodological studies (n = 5, 21%) [32][33][34][35][36]. There was one randomised controlled trial [37] conducted with acquired brain injury patients where camera images formed part of a health intervention.…”

“…There was one randomised controlled trial [37] conducted with acquired brain injury patients where camera images formed part of a health intervention. The majority of the studies were conducted in the United States of America (n = 7, 29%) [22,25,27,29,31,32,36], the United Kingdom (n = 6, 25%) [9][10][11][12][13][14], and Ireland (n = 4, 13%) [24,30,33,35]. Three studies [23,26,28] were international multicentre studies, while the remaining studies were from New Zealand [8,20,34] and Spain [37].…”

“…Feasibility and pilot studies [9][10][11]16,20,[22][23][24][25][26][27][28][29] focussed predominantly on assessing the feasibility of using wearable cameras to capture information on dietary intake/food consumption, physical activity and sedentary behaviour. Studies classified as validation [8,28,30,31] compared the validity of wearable cameras either against, or in combination with other measurement approaches, including self-reported diaries, questionnaires, as well as objective measurement techniques such as accelerometers and doubly labelled water.…”

“…Eight had between 20 -50 participants [8,9,13,20,24,[29][30][31][32][33]36,37] and only three studies (13%) [26][27][28] had more than 50 participants (maximum = 84). Participants were predominantly healthy adults (n= 15, 65%) [8,[10][11][12][13]20,22,23,[25][26][27][28]33,35,36], with some studies including athletes (n = 4, 17%) [24,[29][30][31] and school children (n = 2, 9%) [9,34]. One study used a sample of older women to examine physical activity and sedentary time [32].…”

“…In 21 studies (81%) participants wore a camera for between three to seven days; in one study, participants wore the cameras for seven weeks [37]. Studies classified as primary or secondary data analyses used wearable cameras to measure, observe or validate specific behaviours related to dietary intake (n = 10, 38%) [8][9][10][11]20,[22][23][24][25]39], physical activity (n =5, 17%) [26,27,30,32,40], a diverse range of daily activities such as travel, work and exposure to food marketing (n = 5, 17%) [12,[33][34][35]37], sedentary behaviour (n = 4, 15%) [13,29,31,36] and travel behaviours such as walking, cycling or motorised transport (n = 2, 8%) [14,28].…”