Men need to rethink their diet if they want to become a father someday, because what they’re eating could affect their children's health later. Researchers from Germany and Sweden have collaborated on a study, published in the journal Cell, which looks into the effects a father’s diet has on his children.

“To use computer terms, if our genes are the hardware, our epigenetics is the software that decides how the hardware is used," the study’s co-author Dr. Anita Öst, of the Linkoping University in Sweden, said in a press release. "It turns out that the father's diet reprograms the epigenetic 'software' so that genes needed for fat production are turned on in their sons. At the moment, we and other researchers are manipulating the epigenetics in early life, but we don't know if it is possible to rewrite an adult program.”

Researchers studied male fruit flies for the first step, and found that just increasing sugar in their diet one or two days before mating changed their offspring. There were genetic alterations in the embryo and when it was born, the offspring’s body composition was changed so much it lead to obesity. A diet high in sugar goes through epigenetic changes, which increases a particular gene without changing the individual’s actual DNA.

Epigenetics is a rapidly growing field of interest because of how much power it could have over an individual’s future and their children. It’s the behavior and environmental factors outside of a person’s DNA that can turn genes on and off. In this case, fathers change the genes of their children by eating too much sugar, and if it proves true in human studies it could mean men have a big influence in their children’s health even before they’re born.

"It's very early days for our understanding of how parental experiences can stably reprogram offspring physiology, lifelong,” the study’s co-author Dr. Andrew Pospisilik, of the Max Planck Institute of Immunobiology and Epigenetics in Germany, said in a press release. “The mechanisms mapped here, which seem in some way to be conserved in mouse and man, provide a seed for research that has the potential to profoundly change views and practices in medicine."

In 1908 Thomas Edison said, “The doctor of the future will no longer treat the human frame with drugs, but rather will cure and prevent disease with nutrition.”

So how would these sugary findings change the way we think about medicine? Instead of looking at nutrition as a way to satiate the body, doctors may one day find what we eat to be at the epicenter of many causes of disease, genetic abnormalities, behavioral issues, and learning disorders.

More than 100 years later and we still haven’t fulfilled Edison’s foretelling -- not even close.

Source: Öst A and Pospisilik A. Paternal diet defines offspring chromatin state and intergenerational obesity. Cell. 2014.