The university I attended did not have one or two libraries, but six large libraries. The first time I set foot in these endless hallways of information I was overwhelmed to say the least. When I needed a particular reference for a project, I amazingly managed to find the exact item. I then proceeded to find the exact page I was set out to find in that exact item.
Our genes work much like a library. They contain a plethora of information, and this information provides the body with instructions on how to operate. Your body can actually choose which genes to express, much like my library search. This phenomenon of "reading" specific genes is well recognized and has been given the name epigenetics.
In an article published in Time Magazine in 2010 entitled "Why Your DNA Isn't Your Destiny," the work of Dr. Lars Olov Bygren, a preventative-specialist and researcher, is discussed. Bygren studied the effects of feast and famine on children growing up in Norrbotten, Sweden, in the 1900s.
He discovered that the dietary and lifestyle conditions affected the genetic expression of not only the individual, but also their children and grandchildren. He concludes "it is through epigenetic[s]...that environmental factors like diet, stress and prenatal nutrition can make an imprint on genes that is passed from one generation to the next."
Interesting factoid: A female's oocytes (A.K.A. ovum or egg) are mature during the third trimester while they are still a fetus. This means that half of your genetic material has been influenced by the environment, since your grandmother was pregnant with your mother.
There are many great examples of epigenetics.
In a bee hive there are thousands of worker bees that all serve one bee, the queen bee. The only difference between the queen bee and the worker bee is their food source. The queen bee is the only bee that is allowed to consume the protein-rich royal jelly. Although the queen bee is genetically identical to all of the other bees, she lives up to 28 times longer, grows three times larger, and lays about 2,000 eggs when she is most fertile.
Another example of epigenetics is demonstrated with the metamorphosis of a caterpillar into a butterfly. The caterpillar closes itself in a cocoon at which time it completely dissolves then reforms into a butterfly. The caterpillar has the exact same genes as the butterfly but the genes are expressed differently depending on its life stage.
Epigenetics tells us that we are in control of our genetic destiny. By choosing a healthy diet and lifestyle, we influence optimal genetic expression for ourselves and generations to come.