Since the human genome was largely sequenced in the early 2000s, people have wondered when various aspects of our lives could be personalized based on our genetic profile. The “one-size-fits-all” approach to drug treatment or dietary advice would become a thing of the past, replaced by regimens taking our unique personal differences into account and that are tailored just for us.
Although this personalized treatment approach has become more widely used in medicine, successes in the personalized nutrition arena are slow.
There are various reasons for this, like the multifactorial nature of the diet/health relationship. One’s genes can help dictate disease susceptibility, but various other lifestyle and environmental factors play a role, as well. It has been demonstrated that chronic diet can effectively alter gene function, further clouding the picture.
Another complicating factor is that scientists are still identifying anomalies in our genes (called single nucleotide polymorphisms, or SNPs). These anomalies may leave us susceptible to disease, or conditions that predispose us to disease.
For example, people may possess a SNP that makes them more likely to absorb fat, which could impact body weight or heart disease risk. Someone else may possess a SNP that makes it impossible for them to metabolize a vitamin. Until more SNPs are identified, and their relationship to disease conditions are confirmed, clinicians are working with an incomplete roadmap to base diet/gene recommendations.
A More Complete Picture
None of this is to say using genetic information to tailor diet advice is useless, at this point. For many, having multiple data points on which to base their diet choices is motivating. A clinician who provides his/her patients or clients with a diet regimen based on an analysis of the person’s current diet, a family history profile, phenotype (body fatness, blood biomarkers, etc.) and some limited genetic information offers a more complete picture to build a personalized diet/lifestyle plan.
However, further discovery regarding genetic anomalies is needed if we are to more fully use genetic information to build personalized nutrition programs.
Imagine a scenario where an infant is born and all of his/her genetic information that may be altered by lifestyle choices is available at the time of birth through a simple blood test or cheek swab. If parents know their child has a great likelihood of developing heart disease in middle age, they are likely to adopt diet choices for the child early in life that better support cardiovascular health and lower disease risk. Early adoption of these choices may also lead to greater adherence by the child as they age. By doing so, they can potentially negate the need for statins in their 30s, bypass surgery in their 40s, and the other adverse outcomes that follow this disease path.
To fully capitalize on the growing understanding of the diet-gene relationship, collaboration among many disparate parties, including scientists, insurance companies, health care providers, genetic information providers, food and supplement manufacturers, retailers and regulators will be necessary to bring this game-changing information to fruition.
Nevertheless, the day will come when we will truly be able to build personalized diets and other lifestyle roadmaps based largely on genetic make-up. Until then, available genetic information can only provide a partial picture of the diets that work best for us.
Mitch Kanter, PhD, is the Chief Science Officer at FoodMinds in Minneapolis.