Unfortunately, I have to be the party pooper on this one, George.

The idea of precision nutrition (PN) is alluring, but we are nowhere near where any PN provider can reliably deliver on its promise. To illustrate the complexity behind gene/genomic-based PN:

Nutrigenetics is about how genotypes influence the dietary response. Nutrigenomics is about the effects of dietary components (nutrients) on the expression of genes that regulate critical metabolic pathways. Metagenomics is about the interactions between microbial (think gut microbiome) and host genes and gene expression. We have far too little knowledge to translate what we know into a PN plan that keeps your personal health at optimum. It sounds and looks good on the brochures and websites of PN providers, but I don’t buy it. I had clients who had the interest and the money to take up PN provider's services. Except for nice profiles and charts, they didn’t benefit appreciably.

My approach is to acknowledge the gene/genome/metabolome for what it is: (still) a black box. We “poke” that black box in a trial-and-error fashion using N-of-1 methods, and benchmark the response against functional biomarkers that really matter (vascular function and age, or blood pressure for hypertensives, for example). None of my clinical colleagues would currently go for or recommend DNA-based PN. I don’t rule it out in the future, but that is still far ahead.