Personalized Nutrition: Hype or Hope?
Personalized Nutrition: Hype or Hope?
Just about everywhere you look, tailor-made products and services are transforming the consumer experience. Personalization is the name of the game, whether it’s getting e-mail offers for flights seemingly hand-picked for you, or scrolling through a Facebook feed that’s designed to show you exactly what you want to see. For supplement firms, it means offering consumers more tools that allow them to make the best dietary decisions for themselves, rather than handing out “one-size-fits-all” recommendations.
“Personalization is all about consumers no longer trusting the ‘experts’ and wanting to become more empowered and confident to create their own healthy eating patterns,” says Joana Maricato, research manager at New Nutrition Business. She adds that “consumers no longer see dietitians and health professionals as the experts on food and health, and their beliefs are becoming more fragmented.”
Food and supplement companies big and small are taking notice. Last October, Campbell Soup invested $32 million in personalized nutrition start-up Habit, which aims to offer a variety of tailored approaches to nutrition, including DNA testing, consumer-specific dietary advice, and customized ready-to-eat meals delivered straight to consumers’ doors. And in the supplements space, Maricato points to the “small, but growing, number of companies with personalization concepts.”
“Most large and medium-size players in the market have started to form teams focused on [personalized nutrition], have designed and developed pilots, and started to look for opportunities to participate or win in that space,” Rony Sellam, CEO of personalized health-analytics firm Segterra (Cambridge, MA), tells Nutritional Outlook. Segterra is the company behind InsideTracker, a personalized nutrition service that encourages users to assess the effectiveness of their diet with at-home tests and an online analytics platform buoyed by the advice of health professionals.
Blood testing, wearable devices, apps, and DNA testing are among the many forms personalized nutrition can take today, but which concepts are backed by research, and which are driven primarily by hype?
The Challenge of Nutrigenetics
One aspect of personalized nutrition that’s attracted plenty of attention in recent years is nutrigenetics, the concept of using some degree of DNA testing to arrive at dietary recommendations specific to an individual’s genetic makeup. In theory, nutrigenetics would allow firms to perform a full or partial DNA analysis of an individual and identify single-nucleotide polymorphisms (SNPs)—variations in the genetic code that can sometimes suggest susceptibility to certain diseases, explains Raymond Rodriguez, PhD, professor, Department of Molecular and Cellular Biology at the University of California, Davis (Davis, CA). Then, based on that analysis, the firm would provide dietary recommendations that are optimized for the genetic predispositions of that person.
“Many of the companies in the personalized nutrition market are relying on a small number of SNPs in a small number of genes to make assumptions about diets that can minimize risk for some future disease or disorder,” Rodriguez explains.
But as compelling as the idea of nutrigenetics is, and as affordable as it has become (most commercial tests range from $99–$300 nowadays), do we actually have the published research to back it up? Studies have long found that different people respond differently to the same diet, and that DNA may be associated with those different responses. For instance, a 2014 study found that individuals with a higher number of obesity-associated genetic variants who also consumed high levels of saturated fats were more likely to have a higher body mass intake (BMI).1
But as with many such studies, researchers relied on self-reported dietary information to construct this trial. Meanwhile, the kind of research most needed for nutrigenetics to really get the approval of the broader scientific community—long-term, dietary-intervention clinical studies—is sorely lacking at the moment.
“There are no large-scale clinical studies in relation to personalized nutrition,” says José M. Ordovás, PhD, director, Nutrition and Genomics, and professor, Nutrition and Genetics, at the Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University (Boston). “What we have is a smorgasbord of small, inconclusive, irreproducible studies scattered in the scientific literature that are cherry-picked by the interested parties to support their individual claims.” He adds that he has seen promising early DNA-based research in the areas of weight management and cardiovascular health for certain specific foods and nutrients, but that overall, “we don’t have validated evidence from the perspective of nutrigenetics that the approach really works.”
One reason for the scarcity of clinical research is the difficult nature of studying the relationship between genetics and diet. Hooman Allayee, professor, Departments of Preventive Medicine & Biochemistry and Molecular Medicine, at the Keck School of Medicine, University of Southern California (Los Angeles), explains that while it’s now become relatively easy to obtain high-quality genetic data, it’s much tougher and more costly to build a large-scale, long-term study where the participants are held to a controlled diet. Even then, if an association is found between one or more genetic variants and dietary intake, more rigorous research that controls for both the diet and the particular genetic variant would still be necessary to replicate the findings, says Allayee.
“That kind of rigor is what I think is missing in the field,” Allayee says. “That’s where the hang-up is. People haven’t gone and validated these gene-dietary interactions.”