A mother's taste for high-fat, sugary foods may leave her children susceptible to drug and alcohol abuse later in life.
In animal studies, rats fed a high-fat diet had progeny that weighed more as adults and drank more of the alcohol offered to them by researchers. Likewise, rats born to a mother whose diet consisted of either high-sucrose or high-fructose foods showed a greater predilection for commonly abused drugs such as amphetamine, in comparison to mothers who had dined on regular "rat chow."
"The majority of women in the U.S. at child-bearing age are overweight, and this is most likely due to overeating the tasty, high-fat, high-sugar foods you find everywhere in our society," Nicole Avena, a neuroscientist with the University of Florida's McKnight Brain Institute, told reporters. "The rise in prenatal and childhood obesity, and the rise in number of youths abusing alcohol and drugs, merits looking into all the possible roots of these growing problems."
Avena presented her findings from three studies at the American Psychological Association's annual meeting this week, held in Honolulu, Hawaii.
To test the effect of a mother's diet on offspring during gestation and lactation, pups born to rats under the conditional diets were nursed by mothers fed a regular diet, with both groups switching offspring. Investigators used three to four pregnant rats in each three-month experiment, with 10-12 offspring for each dietary condition. The high-fat diet comprised 50 percent of calories from fat, 25 percent from carbohydrates, and 25 percent from protein — compared with a control comprising 50 percent of calories from carbohydrates and only 25 percent from fat.
The high-sugar diet was tested with both sucrose and fructose, as the source of carbohydrate, given that fructose is chemically different and synthesized from corn. One group of pregnant rats received a diet of regular food plus a 10-percent sucrose solution or a 16-percent fructose admixture. The offspring borne to rats fed a high-sugar diet showed greater response to low doses of amphetamine, suggesting sensitivity to the drug, as did pups who merely nursed from those mother rats. Whether exposed to a maternal high-sugar diet by gestation or lactation, rat pups tended to weigh significantly more later in adulthood.
The experiments bolster previous animal studies showing that gluttonous behavior in humans alters the brain's reward system, and that diets with excessive fat and sugar may lead to increased appetite as well as inclinations toward drugs and alcohol.
"Our findings suggest that even while [rats are] still in the womb, exposure to high-fat and sugar-rich diets can, in addition to increasing body weight, lead to a predisposition to drink alcohol and a sensitivity to drugs," Avena said.