A team from Newcastle University has identified that girls and boys with more eating disorder symptoms at age nine also had a higher number of symptoms at age 12.
A new study published in the academic journal, Appetite, reveals the need to treat eating disorder problems as early as possible to help prevent children developing the life-threatening illness.
The six-year study identified three areas that parents, teachers and doctors should be alert to when looking to detect and help youngsters at risk of the mental health problem.
These factors are: boys and girls with body dissatisfaction, girls with depressive symptoms, and boys and girls who have had symptoms at an earlier stage.
It is believed that this research will help pave the way for early interventions to help young patients deal with their eating disorder.
Dr Elizabeth Evans, Research Associate at Newcastle University's Institute of Health and Society, led the study.
She said: "This research was not about investigating eating disorders themselves, rather we investigated risk factors for developing early eating disorder symptoms.
"Most previous work on children and young adolescents has only looked at the symptoms at one point in time so cannot tell which factors precede others.
"Our research has been different in that we have specifically focused on the factors linked with the development of eating disorder symptoms to identify children at the greatest risk.
"Results suggest the need to detect eating disorder symptoms early, since a higher level of symptoms at nine years old was the strongest risk factor for a higher level of symptoms at 12 years old."
Eating disorders are rare at age nine (1.64 per 100,000) but more prevalent at age 12 (9.51 per 100,000). The most common age for hospitalisation is 15 years old for both boys and girls.
Many more children have symptoms but do not develop a full eating disorder. Symptoms can include rigid dieting, binge-eating, making oneself sick after eating, and high levels of anxiety about being fat or gaining weight. Eating disorders are serious and can be fatal.
For the research, children from a birth cohort, the Gateshead Millennium Study, completed questionnaires about eating disorder symptoms, depressive feelings and body dissatisfaction when they were seven, nine and 12.
The North East has the highest rate of eating disorder hospital admissions in the UK, at approximately six per 100,000. Many more sufferers are treated as outpatients.
The research highlights that some risk factors precede the symptoms of the condition and others occur at the same time.
At age 12, boys and girls who are more dissatisfied with their bodies have greater numbers of eating disorder symptoms. Body dissatisfaction is an important indicator of increased risk of the condition.
Girls with depressive symptoms at 12 years old also have greater numbers of eating disorder symptoms. This relationship was not seen in boys.
The study is being followed up by repeating the questionnaires with the same cohort of children at 15 years old. This will allow researchers to assess what happened next for the youngsters with greater numbers of eating disorders at age 12.
Dr Evans said: "Future studies we do will investigate if our findings with young adolescents hold true for older adolescents, or whether we detect new risk factors.
"Both possibilities will further inform our efforts to promote and target early prevention for eating disorders."