Epigenetics
In plain language
If your DNA is the score, then epigenetics is the way that music is played — which notes sound louder and which stay silent. Your DNA code barely changes throughout your life, but which genes are active differs from cell to cell and from moment to moment. That is regulated by small chemical 'marks' on your DNA and on the proteins it is wound around. What is fascinating is that your environment helps write this: nutrition, exercise, sleep, stress and even the substances your gut bacteria produce can influence those switches. This is partly how epigenetics explains why identical twins with identical DNA can nevertheless age differently. An important nuance: many epigenetic effects are subtle, context-dependent and still very much under research. It is not a knob you can use to flip genes at will, but it is a window onto how lifestyle and biology touch each other.
The science behind
Epigenetic regulation encompasses mechanisms that steer gene expression without altering the nucleotide sequence. The best studied are DNA methylation (usually on CpG islands), histone modifications (acetylation, methylation and others) and non-coding RNAs. Together they determine the accessibility of chromatin and therefore which genes are read.
• DNA methylation. Generally associated with gene repression; dependent on methyl donors from the diet (folate, B12, choline, betaine) — an interface with nutrigenomics.
• Histone modifications. Including histone acetylation, which opens up the chromatin structure. Butyrate, a microbial postbiotic, acts as a histone deacetylase inhibitor — a concrete co-metabolic point of action.
• The environment helps write. Nutrition, exercise, sleep, stress and microbial metabolites influence the epigenome.
• Epigenetic clocks. Methylation patterns are used to estimate biological age — relevant to longevity research.
Epigenetics thus forms a hinge between fixed predisposition (DNA) and changeable lifestyle, and is one of the routes by which the microbiome influences the host. My InnerSelfie treats epigenetic insights at the level of understanding. This reading is supportive and observational — not a medical diagnosis.
Related concepts
Further reading
How lifestyle works through on your biology is a recurring theme in HOST and FORMULA by Petra Van Gucht. See the books →
Scientific references
• Nature, Signal Transduction & Targeted Therapy — microbiota-review (s41392-022-00974-4).
Frequently asked questions
- What is epigenetics?
- The study of how genes are switched on or off without the DNA code itself changing, via marks such as DNA methylation and histone modifications.
- Does epigenetics change my DNA?
- No. The DNA sequence stays the same; epigenetics only influences which genes are active.
- Can lifestyle influence my epigenetics?
- Nutrition, exercise, sleep, stress and microbial metabolites can influence epigenetic marks, although many effects are subtle and context-dependent.
- What does the microbiome have to do with epigenetics?
- Microbial substances such as butyrate act as a histone deacetylase inhibitor and can thereby help influence the host's gene activity.