"You are what you eat," may be a very popular adage, but now there is a high possibility that we may also start saying, "You are what your mother ate."
In a study conducted by researchers at the Yale School of Medicine and the University of Cologne, it was found that the children of obese mothers who subsisted on a high-fat diet during the course of their pregnancy are at a higher risk for obesity and related metabolic disorders all their lives. The study was published in the Jan. 23 issue of Cell.
The researchers developed a mouse model of metabolic programming in collaboration with the Max Planck Institute for Neurological Research. Six mice were fed either a high-fat diet or a normal diet for eight continuous weeks before they became pregnant, and fed the same diet during gestation. When the mice were already nursing their pups, three of them were given a high-fat diet and the other three were given a normal diet.
After the pups all were weaned, they were placed on a normal diet until they were eight weeks old, and then they were broken up into eight different groups. One group was given a high-fat diet and the other a normal diet, for twelve weeks. At the end of this period, the researchers observed that those pups whose mothers were on the high-fat diet when nursing, had been most affected by the diet change in terms of body weight and body fat content.
The researchers also observed a change in the structure of the mice's brains, specifically in the abnormal neural circuits and altered insulin signaling in the offspring's hypothalamus, the key region in the brain that regulates metabolism. These circuits were generated by the consumption of a high-fat diet during lactation. The offspring then remained overweight and experienced problems and abnormalities in glucose metabolism, which persists throughout life.
"Our study suggests that expecting mothers can have major impact on the long-term metabolic health of their children by properly controlling nutrition during this critical developmental period of the offspring," said the study's co-lead author Tamas Horvath. Horvath is the Jean and David W. Wallace Professor of Biomedical Research and chair of comparative medicine at Yale School of Medicine.
Aside from obesity, Dr. Graham Burdge from the University of Southampton, reiterated that it has been well established for the past two decades of research that, "nutrition in early life has lasting effects on cardiovascular disease, obesity, osteoporosis and some cancers."
Burdge, however, said that this study is significant in that it "is an intriguing technical advance showing neurological circuits are being changed, which hasn't been shown before."
"We definitely believe these are fundamental biological processes also affecting humans and influencing how children may eventually become obese," said Horvath. "It seems, at least, that this could have a major impact and we need to explore it further in both animal and human studies."
Obesity has been seen to run in families, because shared eating habits are a major factor in nutrition. A healthy diet is still - and will always be - recommended for pregnant and lactating mothers, to help ensure a healthy child. In addition, healthy eating habits must be encouraged and maintained all throughout the child's life.