Having a baby? You might want to be careful not just what you eat, but how much -- and that goes for dads too.
Kids whose parents were obese are more likely to gain weight when eating the same amount of food as kids whose parents weren't, geneticists have found -- at least in mice.
Researchers in Germany created three groups of mice; the first were fed a high-fat diet and developed obesity and glucose intolerance, the second ate normally, while the third chowed down on low-fat offerings.
Embryos were produced from different combinations of the obese, normal and low-fat groups, and implanted in healthy, normal-weight surrogate mothers. After birth, all the offspring were fed a high-fat diet.
Mice born of embryos sourced from two obese parents gained "significantly more" weight than those with only one, or none. Offspring whose parents lived on a low-fat diet gained the least, despite all the mice being born of equally healthy surrogate mothers.
"In addition to passing on genetic information to their offspring in the form of DNA, parents may also pass on epigenetic modifications to their genetic material -- reversible alterations that affect gene expression but do not change the DNA sequence -- that they acquire throughout their lives," the researchers from Helmholtz Zentrum München said in a statement.
But what isn't known is whether those epigenetic changes came from the mother or father's eating habits.
"Whether environmental conditions, such as the mother's diet during pregnancy or breastfeeding, molecules present in the father's seminal fluid or parental microbiomes are responsible for the inheritance of these epigenetic factors has not yet been established."
The research is published today in journal Nature Genetics.