Diet in Pregnancy More Formative Than Previously Suspected
It’s long been clear that it’s vitally important for pregnant women to eat right. We know, for instance, that women who don’t get enough folate (vitamin B9) in the diet during pregnancy are at significantly greater risk of having a baby born with a neural tube defect, such as spina bifida. That’s why expecting mothers are encouraged to take prenatal vitamins, which contain extra folate, among many other important nutrients. Babies’ growing brains need plenty of omega-3 fatty acids, too, and that’s a nutrient that’s often scarce in the Western diet. It’s abundant in fatty cold water fish, though. That’s an example of a nutrient that acts as an important building block.
Omega-3s are directly incorporated into the cell membranes of growing nerve cells; they’re an integral structural component. Mothers and their babies require adequate supplies of these essential nutrients. But new research has shown that a mother’s pre-conception diet also has an effect on her baby, by switching baby’s genes on or off. This is the relatively new science of “epigenetics”. Certain nutrients facilitate processes that modify genes by flipping biochemical switches.
In recent decades, scientists have discovered that, although the genetic code is, indeed, basically “set in stone,” the ways in which the instructions encoded in the genes are expressed is flexible, depending on epigenetics. Certain factors at play before a baby is even conceived can influence how that baby’s genes will eventually function. An animal study revealed, for example, that a female mouse’s diet before pregnancy could affect genes for coat color among her offspring. Based on the mother’s diet, it was possible to permanently change the color of the fur among her offspring. This has profound implications for the importance of diet and good nutrition, because evidence is mounting that what parents eat may influence their offspring for generations to come. Among humans, some scientists worry that our present relatively poor diets may be triggering generational changes that could lead to inherited diabetes or obesity, among other negative effects. It would certainly give new meaning to the term junk food. the old adage, “you are what you eat” is not only true, but it can now be expanded to encompass one’s offspring: “They are what you ate.”
Paula Dominguez-Salas, Sophie E. Moore, Maria S. Baker, Andrew W. Bergen, Sharon E. Cox, Roger A. Dyer, Anthony J. Fulford, Yongtao Guan, Eleonora Laritsky, Matt J. Silver, Gary E. Swan, Steven H. Zeisel, Sheila M. Innis, Robert A. Waterland, Andrew M. Prentice, Branwen J. Hennig. Maternal nutrition at conception modulates DNA methylation of human metastable epialleles. Nature Communications, 2014; 5 DOI: 10.1038/ncomms4746