What is personalised nutrition?
Internet and mobile phone technology has become integral to our daily activities and health and eating behaviour is no exception with recent technical advances having fuelled a drive towards direct-to-consumer (D-T-C) personalised nutrition. Personalised nutrition is an innovative concept that seeks to identify individual nutritional needs based on health status, genotype( Reference Ronteltap and van Trijp 1 ) and/or phenotype( Reference Boland 2 ) and then to provide healthy eating advice that is tailored to suit the individual (Food4me.org). Meanwhile, there is a growing body of evidence for the effectiveness of tailored feedback in bringing about healthy behaviour change( Reference Gordon, Griffin and Wawak 3 – Reference de Bourdeaudhuij and Brug 6 ). Surveys of D-T-C services have suggested that they are effective in producing healthy behaviour change in approximately one-third of users( Reference Egglestone, Morris and O'Brien 7 – Reference O'Daniel, Haga and Willard 10 ). Awareness of D-T-C genetic tests is increasing among consumers( Reference Finney Rutten, Gollust and Naveed 11 ). Those with a stake-hold in the delivery of personalised nutrition see immense potential to transform preventative and therapeutic nutrition and in doing so, to benefit public health and reduce health costs( Reference Lewis and Burton-Freeman 12 ). Personalised nutrition not only has potential for the tailoring of diet to individual health needs, but also to that of groups of people among the general public( Reference Gibney 13 ). For personalised nutrition intervention to have any real and enduring impact upon public health, however, we need to understand and take into account the public vision for such services( Reference Onwezen, Reinders and van der Lans 14 ). Early D-T-C personalised nutrition initiatives have, on the whole, not been commercially successful. Despite the recent rapid advance in interactive health technology( Reference Lewis and Burton-Freeman 12 ) and the potential for societal benefit, there is a dearth of research in the area of personalised nutrition and nutrigenomics from the perspective of the general public( Reference Su and Lu 15 , Reference de Vrieze, Bouwman and Komduur 16 ). Much of what research exists has focused on genetic testing albeit in various contexts, while fewer studies have considered personalised nutrition in particular.
What do the public think about nutrigenomics?
The future success of personalised nutrition in practice will depend upon the public being ready and able to take up aspects of the technology that are essential to service delivery. Personalised medicine and personalised nutrition share certain technologies. Genetic profiling is common to personalised medicine and nutrition and is likely to be important (along with phenotype, etc.) in informing personalised nutrition initiatives in the future. Understanding attitudes towards genetic testing, therefore, is relevant to understanding public response to nutrigenomics which represents the more ‘medicalised’ level of personalised nutrition provision.
Qualitative enquiry into societal views on genetic testing undertaken in the USA( Reference Glenn, Chawla and Bastani 17 – Reference Doukas, Fetters and Coyne 23 ), Australia( Reference Keogh, McClaren and Maskiell 24 ), Switzerland( Reference Vayena, Gourna and Streuli 25 ), the Netherlands( Reference Wijdenes-Pijl, Dondorp and Timmermans 26 ) and the UK( Reference Skirton 27 ), has indicated that people are aware of the potential benefits and hold generally positive attitudes towards genetic testing. Potential drivers of the uptake of genetic testing include own health( Reference Glenn, Chawla and Bastani 17 , Reference Streicher, Sanderson and Jabs 18 , Reference Keogh, McClaren and Maskiell 24 , Reference Hardie 28 , Reference McGowan, Fishman and Lambrix 29 ), the health of other family members and descendants( Reference Glenn, Chawla and Bastani 17 – Reference Goldman, Kingdon and Wasser 19 , Reference Keogh, McClaren and Maskiell 24 ), for research purposes( Reference Glenn, Chawla and Bastani 17 , Reference Keogh, McClaren and Maskiell 24 , Reference Su, Howard and Borry 30 ) and curiosity( Reference O'Daniel, Haga and Willard 10 , Reference Streicher, Sanderson and Jabs 18 , Reference Keogh, McClaren and Maskiell 24 , Reference Vayena, Gourna and Streuli 25 , Reference Hardie 28 , Reference Su, Howard and Borry 30 , Reference Basson, Futter and Greenberg 31 ). All these studies, however, also catalogued concerns surrounding the enabling technology. Online privacy and the potential for information to be used by companies for commercial gain or to fall into the hands of insurers, employers or government agencies are among issues that have been consistently raised( Reference Glenn, Chawla and Bastani 17 – Reference Skirton 27 , Reference Wilde, Meiser and Mitchell 32 , Reference Nyrhinen, Leino-Kilpi and Hietala 33 ). Aspects of the service delivery system itself may also need to be personalised. Whereas some studies of factors determining uptake of genetic testing( Reference Doukas, Fetters and Coyne 23 , Reference Townsend, Adam and Birch 34 ), have suggested that consumers liked the notion of autonomy and being in control( Reference Nyrhinen, Leino-Kilpi and Hietala 33 ), other works have implied that some consumers would prefer the input of a health professional( Reference Wilde, Meiser and Mitchell 32 , Reference Rew, Mackert and Bonevac 35 , Reference Frazier, Calvin and Mudd 36 ). In view of the differing perspectives, the mode of service delivery may need to be personalised.
Survey studies conducted in the USA( Reference Haga, Barry and Mills 8 , Reference Kerath, Klein and Kern 37 – Reference Durfy, Bowen and McTiernan 47 ), Canada( Reference Etchegary, Cappelli and Potter 48 ), Russia( Reference Makeeva, Markova and Roses 49 , Reference Makeeva, Markova and Puzyrev 50 ), Finland( Reference Toiviainen, Jallinoja and Aro 51 , Reference Aro, Hakonen and Hietala 52 ), Sweden( Reference Hoeyer, Olofsson and Mjörndal 53 ), the Netherlands( Reference Morren, Rijken and Baanders 54 ), Australia( Reference Wilde, Meiser and Mitchell 55 ), Canada( Reference Ries, Hyde-Lay and Caulfield 56 ) and the UK( Reference Sanderson, Wardle and Jarvis 57 ) have indicated largely positive attitudes towards genetic testing. The public also appear positive about donating genetic material to biobanks( Reference Goldman, Kingdon and Wasser 19 , Reference Brothers, Morrison and Clayton 58 , Reference Treweek, Doney and Leiman 59 ) and willing to supply genetic material for research purposes( Reference Pulley, Brace and Bernard 60 ). Reasons suggested by the public for taking up genetic testing not only include improving one's own health( Reference Gollust, Gordon and Zayac 61 – Reference Cappelli, Surh and Humphreys 64 ), but also of other family members and descendants( Reference Akinleye, Roberts and Royal 62 – Reference Bosompra, Flynn and Ashikaga 66 ) . Unsurprisingly, therefore, those with a family history of inherited conditions have been found to have more favourable attitudes towards genetic testing( Reference Catz, Green and Tobin 21 , Reference Wilde, Meiser and Mitchell 55 , Reference Kettis-Lindblad, Ring and Viberth 67 ) and may be willing to pay more( Reference Ries, Hyde-Lay and Caulfield 56 ). A sizeable proportion would avail of genetic testing for no reason other than curiosity( Reference Hull, Sharp and Botkin 42 , Reference Makeeva, Markova and Roses 49 , Reference Makeeva, Markova and Puzyrev 50 , Reference Gollust, Gordon and Zayac 61 , Reference Akinleye, Roberts and Royal 62 , Reference Ormond, Hudgins and Ladd 68 ). Others, on the other hand, may not want to know test results unless treatment was available( Reference Hoeyer, Olofsson and Mjörndal 53 , Reference Morren, Rijken and Baanders 54 ).
Despite generally positive attitudes towards genetic testing, and in keeping with existing qualitative studies into genetic testing (see previous paragraph), quantitative research, mainly surveys conducted over the last couple of decades conducted in the USA( Reference Haga, Barry and Mills 8 , Reference Kerath, Klein and Kern 37 , Reference Ormond, Hudgins and Ladd 68 – Reference Neumann, Hammitt and Mueller 71 ), Canada( Reference Etchegary, Cappelli and Potter 48 , Reference Ries, Hyde-Lay and Caulfield 56 ), Australia( Reference Taylor 72 ), Europe( Reference Gaskell, Allum and Stares 73 ), the UK( Reference Treweek, Doney and Leiman 59 ), Finland( Reference Jallinoja, Hakonen and Aro 74 , Reference Hietala, Hakonen and Aro 75 ) and the Netherlands( Reference Henneman, Vermeulen and van El 76 ) also indicate considerable concern among the public about internet privacy, data security, data use and data destiny( Reference McGuire, Diaz and Wang 41 , Reference Peters, Rose and Armstrong 43 , Reference Singer, Antonucci and Hoewyk 44 , Reference Toiviainen, Jallinoja and Aro 51 – Reference Ries, Hyde-Lay and Caulfield 56 ). Previous surveys into public attitudes towards genomics( Reference Aro, Hakonen and Hietala 52 , Reference Hoeyer, Olofsson and Mjörndal 53 , Reference Wilde, Meiser and Mitchell 55 , Reference Kettis-Lindblad, Ring and Viberth 67 ), however, have failed to recruit samples that have been representative of the general population, making it difficult to draw firm conclusions as to the response of various societal groups to this emerging technology. Attitudes to genetic testing, however, appear to vary by gender, age and educational level. Males( Reference Haga, Barry and Mills 8 , Reference Aro, Hakonen and Hietala 52 , Reference Sanderson, Wardle and Jarvis 57 , Reference Cherkas, Harris and Levinson 63 ) and older individuals( Reference Finney Rutten, Gollust and Naveed 11 , Reference Kerath, Klein and Kern 37 , Reference Aro, Hakonen and Hietala 52 , Reference Sanderson, Wardle and Jarvis 57 ) appear most favourable towards the notion of genetic testing. Analyses of the impact of education level upon attitudes towards genetic testing have produced mixed results( Reference Finney Rutten, Gollust and Naveed 11 , Reference Catz, Green and Tobin 21 , Reference Hensley Alford, McBride and Reid 40 , Reference Donovan and Tucker 46 , Reference Jonassaint, Santos and Glover 77 – Reference Hughes, Gomez-Caminero and Benkendorf 79 ). Those educated to a higher educational level( Reference Catz, Green and Tobin 21 , Reference Goddard, Moore and Ottman 78 ) and those in minority ethnic groups( Reference Peters, Rose and Armstrong 43 , Reference Singer, Antonucci and Hoewyk 44 ) appear particularly concerned over data protection, use and destiny.
What does the public think about personalised nutrition?
Whereas personalised medicine relates genotypic information to propensity for disease, personalised nutrition relates genotypic information to optimal diet and health( Reference Gibney and Walsh 80 ). Personalised nutrition also differs from nutrigenomics in taking a broader view of health and dietary health promotion and considering not only genotype, but also phenotype and lifestyle. This could render personalised nutrition less ethically sensitive and more amenable to public health promotion. However, consumer response to nutrigenomics and personalised nutrition remains an under researched area. Only a handful of qualitative (Morin( Reference Morin 81 )) and survey( Reference Stewart-Knox, Bunting and Gilpin 82 , Reference Roosen, Bruhn and Mecking 83 ) studies have considered the public perspective of nutrigenomics, all of which have indicated that between one-third and a one-half of those surveyed would be willing to avail such services and to follow a tailored diet. Having a health problem was also associated with being positive about receiving genetic-profiling information for the purpose of personalising their diet( Reference Stewart-Knox, Bunting and Gilpin 82 , Reference Roosen, Bruhn and Mecking 83 ). Research conducted in the Netherlands has indicated that consumers may be more amenable towards web-based personalised nutrition if they were in control of the use of the results( Reference Ronteltap, van Trijp and Renes 84 ). In keeping with this notion, other studies have implied that doubts about data security, data use and destiny would deter use of such services( Reference Stewart-Knox, Bunting and Gilpin 82 , Reference Roosen, Bruhn and Mecking 83 ).
The Food4Me project
The EU-funded Food4Me project appears to be the first of its kind to have adopted a mixed, qualitative and quantitative, survey design to gain an understanding of what would determine or deter uptake and compliance with personalised nutrition among the European general public and to establish the best way to deliver such services.
Focus group discussions were held in each of eight European countries (Spain, the UK, Ireland, the Netherlands, Poland, Portugal, Greece and Germany) during early 2012. Discussion was prompted using scenarios that depicted personalised nutrition at three successive levels of ‘medicalisation’ for which lifestyle, phenotypic and genetic information was collected (Food4me.org). The concept of personalised nutrition was viewed positively with potential to enhance health. Discourses arising in all eight countries framed personalised nutrition in terms of perceived benefit and risk( Reference Stewart-Knox, Kuznesof and Robinson 85 ). The sort of benefit expected from personalised nutrition were health related and similar to those which have been previously reported( Reference Gollust, Gordon and Zayac 61 – Reference Cappelli, Surh and Humphreys 64 ) and included those related to health and fitness such as losing weight, building muscle, preventing and treating disease. D-T-C personalised nutrition services were likened to ‘the food equivalent of a personal trainer’. Themes otherwise centred on the online delivery technology. The convenience of accessing dietary health services in the comfort of one's own home directly and not having to involve the general practitioner were also considered advantageous. The potential for anonymity afforded by such a system could serve to spare embarrassment and enable greater honesty in reporting dietary health behaviour.
Perceived risks were unrelated to personalised nutrition per se but rather to aspects of the delivery system itself such as those incurred by unwittingly visiting spurious websites or as a consequence of a lack of online security. Although in favour of personalised nutrition, the European public were unanimous across eight countries in expressing negative views on the ability of web-based enabling technology to ensure privacy and overcome issues surrounding data protection, usage and data destiny( Reference Stewart-Knox, Kuznesof and Robinson 85 ). As has been found in previous qualitative studies of genetic testing( Reference Glenn, Chawla and Bastani 17 – Reference Skirton 27 , Reference Wilde, Meiser and Mitchell 32 , Reference Nyrhinen, Leino-Kilpi and Hietala 33 ) and nutrigenomics( Reference Stewart-Knox, Bunting and Gilpin 82 ), issues surrounding data mishandling arose with concerns expressed about where information could end up. Possibilities discussed included the potential for commercial exploitation, for example, the selling of data to advertisers or spammers, as well as the more sinister possibility of surveillance purposes by insurers, employers and government agencies.
The next stage in the research process was to determine the distribution and generalisability of these ideas quantitatively. The prior qualitative research findings were used to inform the selection of items and validated scales and for inclusion in the Food4Me survey. The resultant questionnaire was translated and back-translated into the native languages of each of the nine EU countries (Germany, Greece, Ireland, Poland, Portugal, Spain, the Netherlands, the UK and Norway) involved in the study. Members of the European public (n 9381) were quota sampled to be nationally representative for each country, on sex, age and education level and then surveyed online during February and March 2013. Similar to the previous surveys of public opinion of genetic testing( Reference McGuire, Diaz and Wang 41 , Reference Peters, Rose and Armstrong 43 , Reference Singer, Antonucci and Hoewyk 44 , Reference Toiviainen, Jallinoja and Aro 51 – Reference Ries, Hyde-Lay and Caulfield 56 ), the Food4Me survey found that perceived benefit was associated with intention to take up personalised nutrition. Statistical modelling suggested that the benefit attributed to personalised nutrition contributed to more favourable attitude towards and intention to adopt personalised nutrition( Reference Poínhos, van der Lans and Rankin 86 ). Perceived benefit was also associated with less perceived risk. Perceived risk was unrelated to intention to take up personalised nutrition. A possible explanation for this finding, and one suggested by the prior qualitative research, is that risk was not actually related to the concept of personalised nutrition but to the online delivery technology.
The Food4Me results, therefore, agree with those of previous studies that have investigated attitudes to genetic testing in suggesting that the public are acutely aware of the threat for data mishandling and misuse. Together, the qualitative and survey results suggest that to encourage uptake of personalised nutrition and enable people to achieve healthy dietary change, we must emphasise benefits while making the delivery system secure. Participants taking part in the initial qualitative studies were able to make suggestions as to how to minimise the damage should a privacy or data-handling mishap occur, for example, storing demographic, lifestyle and biological data separately. Nevertheless, the issue of how to ensure online privacy and protect and control data usage and destiny remains.
What does the future hold for personalised nutrition?
Previous research findings provide some clues as to why despite evidence that tailored interventions are effective in bringing about healthy behaviour change, early attempts to deliver personalised nutrition services on a commercial scale have failed. Expectancy value theories allow us to consider the implications of these findings for behaviour change. Protection motivation theory( Reference Maddux and Rogers 87 – Reference Floyd, Prentice-Dunn and Rogers 89 ) holds that the likelihood of a behaviour occurring, for example, taking up personalised nutrition, will depend upon the perceived size, severity and likelihood of any associated risk and perceived ability to reduce the risk. This implies a need for further consumer research to establish the perceived size, severity and likelihood of risk associated with online D-T-C personalised nutrition as well as perceived ability to reduce the risk and interaction with perceived benefit.
The overarching message from the research into the public response to genetic testing, nutrigenomics and personalised nutrition is that for D-T-C personalised nutrition to be taken up on a societal scale, people will need assurances that all online interactions would be private and that the provider will have ability to effectively handle and protect information collected in the endeavour to design personalised diets. In the wake of accidents resulting in public data falling into the ‘wrong’ hands and recent revelations about how data generated through social media and other personal internet activities is used for marketing purposes and commercial gain, perceived weaknesses inherent in such technology are likely to limit the future development, consumer uptake and growth of such services.
Potential consumers, although positive about the concept of personalised nutrition, are telling us that in order for them to take up such services the information collected will require regulation( Reference Ahlgren, Nordgren and Perrudin 90 ). Control of the handling and use of health-related data will only be effective if the technology is in place to enable compliance with regulation( Reference Bollinger, Green and Kaufman 91 ). Interdisciplinary research and innovation is needed urgently to render the delivery of health systems such as personalised nutrition secure and enable this potentially important public health innovation. Delivering personalised nutrition to the public will require working closely with information technologists in getting the delivery system perfected. Technological innovation has driven the concept of D-T-C health systems. The future of personalised nutrition would also appear to lie in the hands of information technologists. Meanwhile, promotion of personalised nutrition to the general public would do well to emphasise the (personal) benefits of personalised nutrition.
Acknowledgements
The authors would like to take this opportunity to acknowledge the work of the focus group moderators, observers and transcribers for their input into the qualitative study as well as GfK who undertook sampling and data collection.
Financial Support
The Food4Me project received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement no. 265494.
Conflict of Interest
None.
Authorship
B. S.-K. drafted the manuscript and A. R. collected and reviewed the literature. All authors contributed to the design of the Food4Me studies and data collection. L. F. led the work.