Study leader Krzysztof Blusztajn of Boston University describe their discovery -- that choline-related genetic changes that affect breast cancer survival rates in rats -- as "stunning."

The researchers studied rates of female rats whose mothers were fed varying amounts of choline during pregnancy -- standard amounts of choline, no choline at all or extra choline.

The researchers then treated the female offspring with a chemical that causes breast cancer. Although animals in all groups developed mammary cancer, or breast cancer, the daughters of mothers that had received extra choline during pregnancy had slow growing tumors while daughters of mothers that had no choline during pregnancy had fast growing tumors.

"Our study provides additional support for the notion that choline is an important nutrient that has to be considered when dietary guidelines are developed," Blusztajn said in a statement. "We hope it will be possible to develop nutritional guidelines for pregnant women that ensure the good health of their offspring well into old age."

The findings are published in the Federation of American Societies for Experimental Biology Journal.