In the Sacramento-Davis regional area, UC Davis studied back in 2005 how a pregnant mother’s diet impacts her infant’s senses, working with rats. In that study, UC Davis neurophysiologist Dorothy Gietzen studied the brain mechanism in rats that allows them to respond to nutritional stress. The biochemical mechanism that enables animals — likely including humans — to recognize when their diet is deficient in an essential amino acid had been identified then for the first time by researchers at the University of California, Davis. See the article, “Study shows how animals sense when food lacks amino acids.”
The findings by neurophysiologist Dorothy Gietzen and colleagues at UC Davis’ School of Veterinary Medicine have implications for human health, particularly epilepsy, since some forms of epilepsy are influenced by amino acid deficiencies. That is because amino acids are the chemical units that the body uses to construct proteins for growth and development, according to that article. The study has appeared in the March 18, 2005 issue of the journal, Science.
“This constitutes a basic, well conserved mechanism in the brain of mammals that allows them to respond to nutritional stress and seek out food that will improve their chances for survival,” Gietzen said, according to that article. For more than five decades, scientists have known that animals have the ability to sense when their diet is not providing sufficient amino acids. Of the 20 amino acids found in animals, eight of them cannot be produced by or stored in the body and, therefore, must be obtained through the foods the animals eat. These eight are known as “indispensable amino acids.”
Do humans sense whether their diet is deficient? Previous research has shown that animals can sense within a matter of minutes whether their diet is deficient in an indispensable amino acid, making use of a subconscious sensing mechanism that does not depend on taste or smell. For example, if rats are offered more than one type of feed, and the first feed they try is deficient in an indispensable amino acid, they will soon switch to another feed that provides the necessary amino acids. Do you think human babies still in the womb also sense deficiencies in the mother’s diet? How about how a human pregnant mother’s diet influencing the infant’s sense of smell?
Now a new study at another university, according to a December 1, 2010 news release from the University of Colorado, Denver and EurekAlert!, “Study shows pregnant mother’s diet impacts infant’s sense of smell,” shows that a pregnant mother’s diet impacts infant’s sense of smell. Odors in womb sensitize fetus to smells, alters brain development. The major new study shows that a pregnant mother’s diet not only sensitizes the fetus to those smells and flavors, but physically changes the brain directly impacting what the infant eats and drinks in the future. See the December 1, 2010 esciencenews.com article, “Study shows pregnant mother’s diet impacts infant’s sense of smell.”
“This highlights the importance of eating a healthy diet and refraining from drinking alcohol during pregnancy and nursing,” said Josephine Todrank, PhD, who conducted the two-year study while a visiting scientist at the University of Colorado School of Medicine, according to the news release. “If the mother drinks alcohol, her child may be more attracted to alcohol because the developing fetus “expects” that whatever comes from the mother must be safe. If she eats healthy food, the child will prefer healthy food.”
Researchers studying mice found that the pups’ sense of smell is changed by what their mothers eat, teaching them to like the flavors in her diet. At the same time, they found significant changes in the structure of the brain’s olfactory glomeruli, which processes smells, because odors in the amniotic fluid affect how this system develops.
“This is the first study to address the changes in the brain that occur upon steady exposure to flavors in utero and early in postnatal life when the newborn is receiving milk from the mother,” said Diego Restrepo, PhD, co-director of the Center for NeuroScience at the University of Colorado School of Medicine and sponsor of the study, in the news release. “During these periods the pup is exposed to flavors found in the food the mom is eating.” The research, he said, could have important public health implications.
“Many diseases plaguing society involve excess consumption or avoidance of certain kinds of foods,” Restrepo explained in the news release. Restrepo is a professor of cell and developmental biology. “Understanding the factors that determine choice and ingestion, particularly the early factors, is important in designing strategies to enhance the health of the infant, child, and adult.”
In her study, Todrank, now a research fellow with collaborator Giora Heth, PhD, at the Institute of Evolution at the University of Haifa, Israel, fed one group of pregnant and nursing mice a bland diet and another a flavored diet. At weaning age, the pups from mothers on the flavored diet had significantly larger glomeruli than those on the bland diet. They also preferred the same flavor their mother ate, while the other pups had no preference.
“Exposure to odor or flavor in the womb elicits the preference but also shapes the brain development,” said Todrank, whose work was funded by a grant from the National Institutes of Health and was published Dec. 1, 2010 in the Proceedings of the Royal Society B, a major biological research journal.
“From the fetus’ point of view, whatever is in the womb is considered “good”. If your mother ate it and survived to give birth to you then it was probably safe,” she said. “This is a good strategy for a mouse that is foraging for food. It treats those same foods as safe.” Due to the similarities in mammalian development, she said, according to the news release, there is no reason to think that experiments would produce different results in humans.
“What an expectant mother chooses to eat and drink has long-term effects – for better or worse – on her child’s sensory anatomy as well his or her odor memory and food preferences in the future,” Todrank said, according to the December 1, 2010 EurekAlert! news release. “It is not yet clear how long these changes and preferences last, but we are currently investigating that question.”