Obesity is a serious health condition that can plague multiple generations within a family, and scientists are looking for ways to prevent it. A new study shows that the eating habits not just of children but of expectant mothers have the ability to fuel the growing childhood obesity epidemic. For the first time, a team of researchers from Washington University in St. Louis have uncovered a huge dietary problem among women that could last for generations. Their findings, published in the journal Cell Reports, reveal the long-term damage a woman can cause if she eats a high-fat, high-sugar diet, even before she becomes pregnant.

"A mother's obesity can impair the health of later generations," said senior author of the study Dr. Kelle H. Moley, obstetrics and gynecology professor at Washington University’s School of Medicine, in a statement. "This is particularly important because more than two-thirds of reproductive-age women in the United States are overweight or obese."

Obese Women Women who eat unhealthy foods, even before they become pregnant, may put their children, grandchildren, and great-grandchildren at risk for obesity. Photo courtesy of Cate Gillon/ Getty Images

For the study, researchers fed mice a high-fat, high-sugar diet (60 percent fat and 20 percent sugar) from six weeks before a mouse became pregnant up until they weaned their offspring. They found the mother’s mitochondrial DNA, which is responsible for converting food into energy, becomes defective in the unfertilized egg as a result of poor diet choices. Because mitochondria has its own set of genes that are inherited only from the mother and not the father, researchers conclude that the defect is passed on exclusively from the mother’s bloodline.

"Pregnant mouse mothers with metabolic syndrome can transmit dysfunctional mitochondria through the female bloodline to three generations," Moley said. "Our study indicates [the] mothers' eggs may carry information that programs mitochondrial dysfunction throughout the entire organism."

Even when the mouse offspring were fed a healthy, controlled diet of high-protein and low-fat and low-sugar chow, the pups, grand-pups, and great-grand pups developed diabetic problems, such as insulin resistance and other metabolic abnormalities that made them susceptible to obesity. Researchers found when they examined the three generations of offspring’s mitochondria, the deformity was still intact.

This led researchers to believe the same effect would occur for human women. Consuming an unhealthy sugar and fat-laden diet even before conception can cause genetic abnormalities that continue throughout at least three generations, and simultaneously put their offspring at greater risk for both Type 2 diabetes and heart disease.  

"It's important to note that in humans, in which the diets of children closely mirror those of their parents, the effects of maternal metabolic syndrome may be greater than in our mouse model," Moley said. "In any case, eating nutritiously is critical. Over the decades, our diets have worsened, in large part due to processed foods and fast foods. We're seeing the effects in the current obesity crisis. Research, including this study, points to poor maternal nutrition and a predisposition to obesity."

Recently, another new study published in JAMA found the prevalence of obesity among women is higher than in men. The researchers found while conducting the study that between 2005 and 2014, the obesity rate for women rose up to 40 percent. Not only are there more obese women in America, but there is also a larger population of morbidly obese women, which means they have a BMI of at least 40 or higher.

“In our society, children are also exposed to all these unhealthy foods and thus this predicts that these offspring would have a double high -- bad diet and inherited predisposition to develop diabetes and obesity,” Moley told Medical Daily. "We are doing studies now to see if exercise or reversal of the high fat/ high sugar diet in the moms, once they are pregnant, can reverse the outcomes in the offspring generations. Our preliminary results do not look promising.”

Source: Moley KH. Cell Reports.