Until fairly recently it was thought and taught that genetic outputs were irrevocably fixed. Which has led to a common perception that having unfavourable genes will lead to an unfavourable future. Luckily for us, that rather clunky early understanding has given way to a much more fluid and intelligent understanding of genetics and resulted in a new field of study called epigenetics.
Every single thing you think, do, breathe or eat acts as information to your genes and changes the way they behave, minute by minute. Your genes contain instructions to make a protein but the epigenetic environment controls when and if that protein is produced and in what quantity. Epigenetics is why your kidney cells behave differently from your liver cells even though they both contain identical DNA. And epigenetics also explains why we can adapt to our environment, learning how to detoxify alcohol, building more muscle in response to exercise, generating an immune response in the presence of a virus. The genes are always there, but our environment provides the stimulus to turn them on or off.
Epigenetics also explains the way diet and lifestyle can influence your health. For example, if you eat salmon and broccoli today on your yoga course your genes will be expressed in a different way than when you eat fish and chips tomorrow after a long, stressful day at work. You can guess which one is better.
It’s satisfying but not surprising that genetic research tends to support everything we’ve always known about good health: in short, good lifestyle choices result in better gene expression. I love the way this relates back to the things that we’ve always known. So if your granny told you something was ‘good for you’ (fresh air, exercise, broccoli, liver) she was tapping in to the idea that all these things result in improved gene expression. She just didn’t know the biology behind it because no one had unravelled it.
Similarly, if your genes are misbehaving and creating symptoms of disease you can nearly always improve the outcomes by returning to more natural ways of behaving that have served us well for generations.
However, for some people the simple pursuit of a ‘healthy lifestyle’ doesn’t always lead to the smooth running of body systems. For people who suffer with health problems despite a healthy lifestyle nutrigenetics can provide answers. Single nucleotide polymorphisms, or SNPs, mean that some people need more exercise, or more broccoli, or more Vitamin D than others to stay healthy. For people diagnosed with cancer understanding the areas where our bodies need extra support can make all the difference.