Nutrigenomics
In plain language
Nutrigenomics is about the conversation between your plate and your genes — in two directions. On the one hand, your genes help steer how you respond to food: one person metabolises caffeine slowly, another breaks down lactose poorly, yet another needs more folate. On the other hand, nutrients themselves can influence the activity of genes — they switch certain 'switches' on or off, as it were. This makes clear why 'the perfect diet for everyone' does not exist: your biology is partly personal. The nuance is important, though: a gene variant is a predisposition, not a fate. That predisposition is often adjusted by your lifestyle and by your microbiome, which in turn converts food. Nutrigenomics is therefore not a promise of a guaranteed DNA-tailored diet, but a lens for better understanding why your body reacts the way it does.
The science behind
The field generally distinguishes nutrigenetics (how genetic variants influence the response to food) and nutrigenomics in the narrower sense (how nutrients modulate gene expression and signalling routes). In practice both are often discussed under a single heading.
• Gene variants & response. Well-known examples: LCT/MCM6 (lactose tolerance), CYP1A2 (caffeine metabolism), MTHFR (folate metabolism), FUT2 (secretor status and microbiome), ALDH2/ADH1B (alcohol).
• Food steers gene expression. Nutrients and their metabolites act via transcription factors and receptors (for example PPARs) and via epigenetic mechanisms — an interface with epigenetics.
• Microbial intermediate layer. Many dietary effects run via the microbiome, which converts food into bioactive metabolites (co-metabolism). Genetic predisposition is thus nuanced by microbes.
• Cautious interpretation. Effect sizes of individual variants are usually small; single gene-diet claims are often exaggerated.
My InnerSelfie never reads genetic predisposition in isolation, but always nuanced by microbiome and metabolome. This reading is supportive and observational — not a medical diagnosis.
Related concepts
Further reading
The interplay between nutrition and biology runs through FORMULA and HOST by Petra Van Gucht. See the books →
Scientific references
• Lee et al. (2024), The human gut microbiome in health and disease.
• Harold McGee, On Food and Cooking (food chemistry as background).
Frequently asked questions
- What is nutrigenomics?
- The study of the interplay between nutrition and genes: how food influences gene activity and how gene variants steer your response to food.
- What is the difference between nutrigenetics and nutrigenomics?
- Nutrigenetics looks at how your gene variants influence your response to food; nutrigenomics looks at how food steers the activity of your genes.
- Does a gene variant mean I am not allowed to eat something?
- Usually not. A variant is a predisposition, not a prohibition. The predisposition is often adjusted by lifestyle and by your microbiome.
- Can a DNA test determine my perfect diet?
- No. The effects of individual genes are usually small and are nuanced by microbes. It gives insight, not a diet guarantee.