Everyone’s heard it before: Change your diet, change your life. But what if changing your diet meant changing your great-great-great-grandchildren’s life?
What is Epigenetics?
In a growing field of study known as Epigenetics, (literally “above the genome”), researchers are discovering that certain genetic traits can be acquired environmentally and then passed on hereditarily. This happens when a change occurs in gene expression, but not the actual DNA sequence. The process, called methylation, is when clusters of atoms attach to genes; these clusters of atoms restrict or permit the gene’s communication with the rest of the body.
In short, certain genes can be essentially switched on or off in reaction to environmental stimuli. The particular patterns of methylation can occur as result of exposure to certain pollutants, diets, and other chemical stimuli such as cortisol, the stress hormone.
The order and frequency of these switches can help determine a person’s genetic profile and potentially what diseases or conditions someone may develop over the course of her lifetime.
That's Great, But How Does It Affect Me (And My Grandkids?)
So, have you ever wondered why certain health goals seem elusive? Are you not any closer to that 9-minute mile than you were a year ago? Good news! It maybe your grandparents’ fault!
A person’s tendency to gain weight and develop diabetes can be determined before they are even born. One study
showed a dramatic predisposition toward obesity in adult men whose mothers were exposed to famine while pregnant and malnourished during the first trimester of their pregnancy. Is this adaptive? Can it be corrected for? Scientists are working to understand exactly what is occurring on the genetic level that would cause such an outcome. Another study on transgenerational epigenetics known as the Overkalix Study (Overkalix, Sweden), found some peculiar gender specific results. Scientists found that the childhood Body Mass Index (BMI) of boys whose fathers started smoking tobacco at a young age was unusually higher than those whose fathers did not smoke at all. Curiously, this correlation was not found in their daughters.
The Nature Vs. Nurture Paradox
Are we doomed to suffer the genetic hand our ancestors dealt us? Must we endure the consequences of the unenlightened health choices made by people whose cigarette smoke filled lives preceded the invention of the stationary bicycle? Well, the good news is that gene regulation works both ways. You can change your genetic fate. What’s even more encouraging is that you’re not just doing it for you, but potentially for every single one of your descendants.
Scientists have also found desirable outcomes in gene expression effected through healthy living. A study
done in 2014 at the Karolinska Institute in Stolkholm (yes, Sweden again) concluded that regular exercise triggered a gene expression that changed the DNA of skeletal muscles making them more resilient and more efficient at recovery. This is not just to say that exercise is good for your muscles, it literally changes the genes in your muscles and consequently, those genes can be passed down to children.
In Short, Go For That Jog!
The full scope of transgenerational epigenetics is still relatively unknown, and the concept of the environmentally influenced genome remains controversial. Some scientists are hesitant to endorse the theory that the health choices a person makes today can have consequences on future generations. So in summary, although the extraordinarily complex human genome is not fully understood even by the most brilliant scientists in the world, there is a high likelihood that your good healthy habits will be felt for years to come, and not just by you.
Exercise doesn’t just change the muscles in your jeans, it changes the genes in your muscles.