I am absolutely fascinated by the field of epigenetics, or more specifically, the study of epigenetics that looks at genetic markers passed down from one generation to the next. In other words, the lifestyle you lead may end up being forwarded to your children if you are in stage of your life when you are wishing to conceive.
Take this study, for example from Cell Metabolism:
Obesity and Bariatric Surgery Drive Epigenetic Variation of Spermatozoa in Humans
Obesity is a heritable disorder, with children of obese fathers at higher risk of developing obesity. Environmental factors epigenetically influence somatic tissues, but the contribution of these factors to the establishment of epigenetic patterns in human gametes is unknown. Here, we hypothesized that weight loss remodels the epigenetic signature of spermatozoa in human obesity. Comprehensive profiling of the epigenome of sperm from lean and obese men showed similar histone positioning, but small non-coding RNA expression and DNA methylation patterns were markedly different. In a separate cohort of morbidly obese men, surgery-induced weight loss was associated with a dramatic remodeling of sperm DNA methylation, notably at genetic locations implicated in the central control of appetite. Our data provide evidence that the epigenome of human spermatozoa dynamically changes under environmental pressure and offers insight into how obesity may propagate metabolic dysfunction to the next generation.
The study tracked 6 men undergoing weight loss surgery. They found that there were thousands of genetic markers, known as methylations, from 3 very different points - prior to surgery, immediately following surgery, and one year following.
It is not entirely known what all of these genetic markers mean, but it is clear that there are changes being made at a genetic level for individuals who have lost weight. Or, another way to look at it, children of obese fathers unfortunately run a greater risk of being obese themselves, for no other reason than because their fathers were overweight around the time of conception.
Up until now, it seemed quite likely that obese children become obese due to the lifestyle. If you grow up in a household where your parents are making poor nutritional decisions, or are inactive, then there is a greater likelihood that those personality traits will be passed on. Unfortunately this study tells us a more startling tale. Even if an individual wishes to change their lifestyle, they may have more of an uphill battle based on their parents' lifestyle choices at the time of conception.
This isn't all bad news, however, as I always say that information is power. Nobody gets to choose their parents, we just have to play the cards we are dealt. However, if you can find out more information about your parents' lifestyles at the time of your conception, you may have a better indication of how strict you need to be in order to maintain a healthy body weight, for example.
And, if you are an aspiring father, strongly consider dropping some weight and improve the genetic markers that get passed on to your children!
Tyler Robbins B.Sc. CSCS
Director of Fitness
Head of CrossFit