You can blame sugar but not your parents for holes in your teeth, with new research showing decay is all down to diet and not your genes*.
A study of 485 sets of twins has revealed the “good” bacteria protecting your teeth is reduced with excessive* sugar consumption* rather than being caused by habits passed on from your parents.
The research, which involved staff from Melbourne’s Murdoch Children’s Research Institute (MCRI), backs the message that good diet and oral hygiene* can prevent* cavities.
After examining 205 sets of identical twins and 280 sets of fraternal twins the research showed there was almost no difference in the rates of tooth decay among those who shared the same genes to those who were non-identical.
Identical twins have the same genes, which means they are the same sex and usually look very similar. Fraternal twins have different genetic make-up and they look less similar.
Just as the study was able to rule out a genetic cause for the decay, the MCRI’s Assoc Prof Jeff Craig said the fact each pair of siblings grew up in the same household showed the impact of their diet and environment.
“What happens with our teeth is a battle between the good and the bad bateria,” Assoc Prof Craig said.
“It wasn’t genetics controlling this battle … sugar was really helping the bad bacteria defeat the good ones, therefore starting off the tooth decay and giving the kids cavities.”
The study led by the J. Craig Venter Institute in the US and published in the Cell Host & Microbe journal yesterday is the first to examine the role of bacteria on teeth.
Although genetics* was found to contribute to many types of bacteria found in a person’s mouth, Assoc Prof Craig said they did not form cavities and instead some created a protective microfilm* on teeth.
“You’ve heard the phrase ‘by the skin of my teeth’ — well that is the reality, bacteria are skin on your teeth. We really don’t know everything that we do with that protective skin,” he said.
Melbourne identical twins Keeley and Emily have been involved in MCRI research for all of their nine years, and their mother Rebecca is not surprised by the latest findings.
“My girls go to the dentist every six months, brush their teeth every day and we keep sweets to a minimum,” she said.
- genes: genetic information inherited by children from parents
- excessive: too much
- consumption: something which is eaten or ingested
- oral hygiene: heath and cleanliness of mouth
- prevent: stop
- genetics: inherited characteristics
- microfilm: a thin layer
LISTEN TO TODAY’S STORY
1. Tooth decay
In a few sentences, describe what causes tooth decay and what the MCRI did to find this out.
Why did the researchers choose this method?
Write a radio advertisement designed to help parents understand what causes decay and give them at least three tips to help them keep their family’s teeth healthy.
You can write a song or jingle as part of your ad. Record your ad if you can.
Time: allow 60 minutes to complete this activity.
Curriculum links: Health and Physical Education, Science, Media Arts
2. What do you know about teeth?
- What are teeth for?
- How and when do we get teeth?
- How many teeth do we have?
- What are the different types of teeth in a human mouth?
- What does each type of tooth do?
Research any questions you can’t answer already.
Think about the different types of teeth that animals have. Choose one animal and find out the answers to the questions from activity two for that animal.
Draw a chart comparing human teeth with animal teeth. Use diagrams or drawings.
Time: allow 85 minutes to complete this activity.
Curriculum links: Health and Physical Education, Science
Search through the story for all the adjectives you can find. Group them into lists of how many syllables are in each word has.
Time: allow 10 minutes to complete this activity.
Curriculum links: English, Big Write, VCOP