Pregnant women who eat too many fatty and sugary foods while pregnant could be putting their children at risk of alcohol and drug problems later in life, according to studies in rats.
The team of researchers was led by Dr. Nicole Avena, who recently presented her findings at the American Psychological Association’s annual convention on the paradise island of Oahu.
The three studies lasted around 3 months, and involved three to four rats and 10 to 12 pups in each. During the course of the studies, researchers found that the offspring of those rats that ate diets high in fat or sugar weighed more when they grew up and drank more alcohol.
Additionally, rats whose mothers fed on high-sugar diets had stronger responses to drugs that are commonly abused, such as amphetamines.
Dr. Avena, who is a research neuroscientist at the University of Florida, says:
“The majority of women in the US 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.
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.”
The researchers tested both sucrose and high-fructose corn syrup on the rats to see if the foods’ chemical differences also caused varying results. Whereas sucrose occurs naturally, high-fructose corn syrup is manufactured from corn.
The rat pups whose mothers ate either of the sugary diets showed no differences in levels of triglycerides – fats in the bloodstream that can increase heart disease risks – compared with those whose mothers ate a normal diet containing 25% fat, 50% carbohydrate and 25% protein, which is the recommended dietary mix in humans.
However, pups whose mothers ate a recommended human diet but that were then nursed by other rats on high-sucrose or high-fructose corn syrup diets while pregnant, became hyperactive after researchers gave them low doses of amphetamine. This suggests these rats had a sensitivity toward the drug.
In addition, the pregnant rats that ate high-fat diets – containing 50% fat, 25% carbohydrate and 25% protein – yielded offspring with higher levels of triglycerides.
These pups also drank much more alcohol in adulthood than their counterparts whose mothers ate a normal, recommended diet.
The researchers point to previous studies, which show that overeating good-tasting foods alter “brain reward systems.”
Dr. Avena adds:
“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.”
The results of the three studies, according to the researchers, may have implications for what kind of prenatal diets medical authorities suggest for pregnant women.