Diet advice aimed at the general population isn’t doing the job. Could personally tailored recommendations based on genetic testing be the answer? By Nick Hughes.
How do you get people to eat a healthy diet? It’s a question that has flummoxed policymakers in the UK for years with no real sense that they have hit on the right approach.
Centralised information in the form of the government’s Eatwell plate sets dietary guidelines at a population level, yet the majority of us fail to heed its advice – the latest data from the National Diet and Nutrition Survey suggests that we eat more than the average recommended intake of red and processed meat and are nowhere near hitting our five-a-day fruit and veg target.
But what if dietary advice were targeted at an individual level?
Welcome to the world of personalised nutrition – a fledgling but rapidly developing area of public health in which people can receive individual interventions, through an expert or dietician, based upon their unique genetic profile and associated health risks.
The subject provided a fertile topic for conversation at November’s Food Matters Live event where, in a session dedicated to personalised nutrition, Dr Barbara Stewart-Knox, a professor of psychology at the University of Bradford neatly summarised its premise: “If you have this particular genetic propensity and if you do nothing then this is the possible outcome.”
Through personalised nutrition interventions people found to be susceptible to heart disease, for instance, might be encouraged to consume foods containing more B-vitamins and antioxidants. Genetic assessment can also be used to highlight previously unknown intolerances or allergies, such as to lactose or gluten, or to indicate whether your caffeine consumption might be a problem based on your metabolism – insights which could affect what foods we eat.
The business community is already looking to grab a slice of the pie. Private companies such as the US firm 23andme have inserted themselves into the market, offering direct-to-consumer nutrigenetic testing whereby the customer’s DNA is analysed via a saliva sample and they receive a genetic test report accompanied, in many cases, by personalised advice on nutrition. Such businesses are careful to stress that their reports are intended for informational purposes only and do not diagnose disease or illness, but clearly there is potential for companies to partner with food or supplements suppliers to cross-sell their products or to integrate a food offer into their own nutrigenetic testing business.
Some companies already sell genetic data to third parties with the customer’s explicit consent in order for products to be targeted at individuals. While many consumers are happy to allow such information to be shared, “for some people there are serious concerns about how their data would be protected, if at all”, according to Dr Sharron Kuznesof, a lecturer in food consumer research at Newcastle University.
Concerns about privacy aside, there is caution about the current strength of the evidence base for public health interventions based on genetic profiling. In response, the EU initiated the Food for Me project in 2011, which brought together an international group of experts to explore the application of individualised nutrition advice, investigate consumer attitudes and produce new scientific tools for implementation. A white paper published in May 2015 concluded that the mere fact that an individual received dietary recommendations on a personal basis was already enough to positively affect dietary behaviour; however, adding genetic information into the advice could not be shown to result in greater effectiveness at this stage.
There is evidently still a way to go in establishing the efficacy of personalised nutrition as well as a lack of clarity about its implications for the foodservice and food retail sectors. But with the obesity crisis escalating and population- level health advice patently failing, many hopes will be pinned on it becoming the magic bullet the public health community has been yearning for.
