If you couldn't get enough
of sweets when you were young, chances are your child
will share your palate's passion.
That's because your taste
preferences are, at least in part, influenced by your
genes. However, age and culture can eventually override
this genetic influence, a new study finds.
And that means kids who
steer clear of vegetables may warm to them in a few
years.
Building off the recent
discovery of taste genes, especially the TAS2R38 genotype
that has receptors for bitter taste, researchers compared
taste preferences between mothers and their children.
"This gene can predict
sensitivity to one type of bitter taste," said study
author Julie Mennella, a developmental psychobiologist
at the Monell Chemical Senses Center in Philadelphia.
However, even when both
mother and child shared the same taste genes, Mennella
said, "When you compare children to adults, children
were much more sensitive than adults." That difference,
she said, "may be reflecting developmental changes that
occur with age."
Results of the study
appear in the February issue of Pediatrics.
The researchers obtained
genetic samples from 143 children between 5 and 10 years
old and their mothers. Based on the genetic analysis,
they were then divided into three groups: Type AA with
two bitter-insensitive genes, type PP with two bitter-sensitive
genes and type AP with one of each.
All were asked to drink
three different concentrations of a bitter-tasting substance
and rate it as either "like water" or "bitter or yucky."
Seventy percent of children
and half of the mothers who were either type PP or AP
said they tasted bitterness in the weakest solution,
but less than 10 percent of those in the AA group did.
Age affected the ability
to taste bitterness. Only 43 percent of the mothers
in the AP group said they could taste the bitterness
in the weakest solution, compared to 64 percent of the
children in that group.
In mothers, Mennella
said, the strongest predictor of a preference for sweet
tastes was culture. According to the study, people of
African descent are much more likely to prefer sweet
tastes than people of European descent.
This study "may help
health-care professionals understand parents' lost battles
over mealtime, because there may be a genetic predisposition
to disliking vegetables," said Angela Kurtz, a pediatric
nutritionist at New York University Medical Center.
But, "despite genetics, parents need to make sound decisions
when it comes to feeding their children and making choices
at the supermarket."
"You can always find
another choice that's a little bit better," said Kurtz.
Instead of muffins and frosted cereals, she suggests
pound cake or graham crackers. If your child likes sweet
beverages, then buy 100 percent juice and dilute it,
and avoid the high-fructose brands. This way, she said,
they're still getting sweet things, but they're healthier
choices.
And, she said, it's important
to keep introducing new healthy foods, though she admitted
that can be a challenge.
"Some studies have found
that it may take being exposed to a new food 50 times
before it no longer seems new," said Kurtz. So, keep
putting one piece of broccoli on your child's plate,
but never force him or her to eat it. Suggest they try
it, and let them see you eating it. Eventually, they
might try it, she said.
Mennella said her study
highlights the need for parents to appreciate the difference
between adults and children.
"Children live in their
own sensory world," she said. "A child may reject a
food that mother or father feels tastes good, but the
child may be perceiving a different taste."
She recommended introducing
vegetables to your children when they're young.
Someday, she said, this
knowledge might lead to new ways to prepare foods that
could mask the bitter taste.