How can 21st century public health research overcome the long-standing frustration associated with dietary assessment?

Abstract

Dr Nisreen Alwan and Janet Cade from the Nutritional Epidemiology Group at the University of Leeds investigate how information and communication technology methods can be used to standardise dietary assessment and close the data gap to reduce global disease burdens.Back in 1981, Doll and Peto said; 'Diet is a chronic source of frustration and excitement for epidemiologists'.1 Thirty years later, this is still the case. Studying the association between diet and health is becoming an increasingly important and topical area of health research in the second decade of the 21st century. For example, all of the top three most read research papers in the British Medical Journal at the time this article was written were in the field of nutritional epidemiology.2,3,4 Diet features very strongly as a risk factor for the top adverse health outcomes in the recently published Global Burden of Disease Study 2010 (GBD 2010).5 Out of the top twenty leading risk factors contributing to the burden of disease in 2010, six are dietary factors (diet low in fruits, nuts and seeds, whole grains, vegetables, seafood omega-3 fatty acids, and diet high in sodium), and another seven are directly linked to diet (high blood pressure, high body mass index, high fasting plasma glucose, childhood underweight, iron deficiency, suboptimal breastfeeding and high total cholesterol).5These findings highlight big opportunities for disease prevention, but they also raise big challenges and frustrations as Doll and Peto pointed out. One of the greatest challenges in specifying causal links between dietary exposures and disease and identifying successful public health nutritional interventions is the profound problem of measurement error. This is associated with all the commonly used dietary assessment methods in population health research, such as food frequency questionnaires; food diaries; and interviewer-administered dietary recalls. Measurement error of dietary exposures comes up as a study limitation in almost any research study linking diet to health outcomes. There are also other significant obstacles to obtaining high quality population level dietary data. These include the relatively high cost associated with the current dietary assessment tools of administering, mailing, collecting and coding dietary data, as well as the low participant response rate due to the time and effort associated with completing them. There has been little progress during the last 30 years in developing new methods that attempt to address these obstacles. Innovative population level dietary assessment methods that combine accuracy and reliability with feasibility, acceptability and low cost to assess nutritional exposures and deliver dietary interventions on a large population scale are urgently needed.The rapidly increasing use of information and communication technology globally, including the Internet and smartphones, provides a golden opportunity to achieve this. A recent World Bank report states that about three-quarters of the world's population has access to a mobile phone.6 The number of mobile subscriptions globally has grown from fewer than one billion in 2000 to over 6 billion in 2012, of which nearly five billion were in developing countries. More than 30 billion mobile applications (apps) were downloaded in 2011, with evidence of use across both the social and economic spectrum.6 Using internet and smartphone app-based dietary assessment tools linked to automated food databases to instantly generate macro- and micro-nutrient data is a promising new development for the future. …