Isabelle Razis

Epigenetics: How do our Choices Shape our Biology?

We should all be thankful for science. Without the progress of science and the passion of the scientific community, we would still be in dark ages. Thanks to science, we have drastically changed our means of communication, the way we work, our housing, our food, our transportation, and so much more. What is even more important in today’s challenges in the field of health, is that science gives us continuously new means of understanding on how our body performs. Hence, science reveals how we should respond to our needs in an environment which is attacking us in various ways. Again, it is our lifestyle choices that will be our saviours… 

In that aspect, I recently followed a course, held as masterly as one would expect from a highly respected educational institution like Stanford University. More specifically, I am referring on a course on epigenetics called “Diet and Gene Expression: You are what you eat” by Dr Lucia Aronica (, Nutritional Genomics at Stanford Continuing Studies and Stanford Sports Medicine. 

There was no way I could keep this valuable information and knowledge only for myself. On the other hand, claiming that I could restitute in a few paragraphs all the information received would obviously be an offence to the professors who presented their findings. Nevertheless, sharing some bits and pieces is useful. It could be a trigger for a deeper understanding of this part of science. 

What is epigenetics? 

Did you know that only 0,1% of our DNA is different than the one of our neighbour’s? What makes each of us different is epigenetics and not genetics. 

More precisely, it has been proved that on top of our genes, there is a second genome called the epigenome. The epigenome is made of molecular switches that can turn a gene on and off just like a dimmer! And, these switches are called epigenetic marks. Actually, the word epigenome comes from Greek where “EPI” means above. The epigenome is what comes above the genome. 

Think of our body as a computer where the genome is the hardware, and the epigenome is the software. We can’t change our genome, our genes, but we can change our epigenome. 

We can use different software which will have an impact on the hardware. Thus, how can we choose or modify the software? This is all about lifestyle choices. More precisely, this means that we can have an impact on our epigenetic marks since they can be modified by our lifestyle choices. 

In the end, each human holds a book he has been born with (the genome). But each human is also the author of his own book, and this is what makes him unique (his epigenome).

One of the most interesting parts of the science of epigenetics is that our epigenome can be inherited. This means that the changes in genes through lifestyle are inheritable; those gene’s activation or deactivation are transferred from our parents and grandparents. 

More particularly, it is now proved that our parents and grandparents environment and lifestyle choices have an impact on our own epigenetics. 

In 2010, there was a famous article in the Times magazine with the title “Why our DNA isn’t your destiny?”. This was all about how the lifestyle choices we make can change our genes’ expression but, also, and what’s even more important, those of our children and grandchildren. 

We can literally change not only ourselves but even the generations to come!

It has even been proved that most autoimmune diseases such as lupus, hashimoto, multiple sclerosis and others do not only occur from our genes. The expression of the genes that cause autoimmune diseases to manifest can be turned on or off by environmental factors. 

But, what are the epigenetic marks, the triggers, that can trigger on or off our gene’s expression?

1. Our diet is epigenetic mark no 1. Thus, this is the reason why we now claim with certainty “We are what we eat”.  

2. The stress we create to ourselves induces inflammation throughout our bodies. 

3. A regular physical activity decreases the levels of inflammation. 

4. Environmental toxins affect our health negatively. 

5. Smoking and alcohol are genes’ enemies. 

Such triggers impact what we are and our predisposition. They are dynamically remodelled during development and influenced by our personal choices. 

Theories such as “personalized medicine” and diet advocating a tailored approach based on predicted response to a specific treatment/diet, or, even the theory of “hormesis response” proved to be real due to epigenetic modifications are concepts that derive and are explained by the science of epigenetics. Other recent concepts such as “inflammaging”, explaining ageing based on the inflammatory levels of elderly organisms, or, “geroscience” combating ageing as a global fight against all diseases are also deriving from epigenetics. 

All the above mechanisms and many more provide us deep comprehension of how our organisms integrate and react upon environmental cues. This global comprehension allows us to give sense to biological phenomena and to how we can have control over our existence and our evolution as humans both on a short term but also on a long term basis.