"Is your child a fussy eater? It could be down to genetics not parenting," the Daily Mirror reports. A study involving twins suggests food fussiness as well as food neophobia – unwillingness to try new foods – may partially be the result of genetics.

The researchers looked at differences in parent-reported behaviour between identical twins (who share 100% of their DNA) and fraternal twins (who share 50%) to estimate the influence genetics had on eating attitudes.

They estimate that for food fussiness, 46% of cases may be down to genetic influences, and for food neophobia, 58% may be down to genetic influences.

Shared environmental influences were also found to play a role, particularly for food fussiness.

The fact that the research found a strong genetic influence on both food fussiness and refusal to try new food might reassure parents, who often feel judged or guilty for their child's fussy eating.

However, despite a strong genetic basis, children's behaviour can be changed. The researchers themselves stressed in their conclusion that "parent-led eating behavior change programs to fussy or food neophobic young children is likely to be effective in decreasing their expression [gene influence]".

Where did the story come from?

The study was carried out by researchers from the Department of Epidemiology and Public Health, University College London, UK and the Department of Psychology, Norwegian University of Science and Technology (NTNU), Norway.

The study was published in the peer-reviewed Journal of Child Psychology and Psychiatry on an open-access basis and is free to read online.

The study was funded by Cancer Research UK and the authors do not state any conflicts of interest.

The Mirror reports: "Toddlers who are fussy eaters are born with the trait" which does not give a balanced view of the findings.

The Times also jumps to blaming fussy eating habits as being "down to genetics" which is not strictly what the study found.

The Guardian presents a fairer picture, reporting that "fussy eating and a refusal to try new foods are both heavily influenced by the child's genetic makeup, and are not just a result of upbringing."

What kind of research was this?

This was a prospective population-based birth cohort study, following a large number of twins over time; which is known as a twin study. Researchers wanted to see if genetic and shared environmental factors contributed to food fussiness and food neophobia.

This type of study can show links between two things, but cannot prove exactly how factors (in this case, genes or the shared environment), cause another (food fussiness or refusal to eat new foods). Identical twins share the same genetic code, whereas non-identical twins usually share their upbringing and parenting, i.e. the environmental influence on food fussiness. By comparing the two it is possible to get an idea of how much of the link is hereditary.

What did the research involve?

Researchers took data from Gemini, a population-based birth cohort of 1,932 sets of twins born in England and Wales in 2007. Of these twins, 626 pairs were identical (share 100% of their genes) and 1,306 were non-identical twins (sharing roughly 50% of their genes).

It aimed to assess the genetic and shared environmental influence on food fussiness and refusal to eat new foods.

Parents completed the "food fussiness" scale of the Child Eating Behaviour Questionnaire for each twin at 16 months of age.

The food fussiness scale includes questions indicating both food fussiness, such as whether the child enjoys a variety of meals and if the child is difficult to please with meals, and food neophobia questions, such as the child's interest in tasting unfamiliar foods.

The relative importance of the shared environment and genetics to variation in food fussiness and new food phobia was assessed by comparing identical and non-identical twins. The extent to which food fussiness and food neophobia share common genetic and environmental influences was also assessed.

A higher correlation for identical twins would indicate the influence of genetic contributions to food fussiness and food neophobia.

What were the basic results?

The results from the 1,932 sets of twins showed that food fussiness and food neophobia were positively correlated (r=0.72, p<0.001), showing those who were fussy eaters also tended to refuse new foods.

For food fussiness, 46% of the variation was explained by genetic influences (95% confidence interval [CI] = 0.41 to 0.52) and, equally, 46% by shared environmental influences (95% CI= 0.41 to 0.51).

For food neophobia, 58% of the variation was accounted for by genetic influences (95% CI= 0.50 to 0.67), and only 22% by shared environmental influences (CI= 0.14 to 0.30).

How did the researchers interpret the results?

The authors concluded that there "is significant genetic influence on food fussiness and food neophobia during early life. Shared environmental effects were found to explain a significantly greater proportion of the variation in food fussiness than food neophobia [new food phobia], suggesting that experiential factors in the home environment appear to be the most salient in explaining etiological differences in interindividual variation of food fussiness compared to food neophobia."

Conclusion

Children who were fussy eaters were also likely to refuse new foods, with many environmental and genetic factors common to both behaviours.

Both food fussiness and food neophobia are heavily influenced by a child's genetic makeup at 16 months of age. Shared environmental influences also have an influence, but more for food fussiness than for refusal to try new foods.

A strength of the study was the large sample size, however there are some limitations:

The food fussiness and food neophobia were reported by parents and may be subject to bias and report inaccuracy.

Twins are more likely to experience feeding difficulties, have a lower birth weight or be born more prematurely, which could influence their feeding habits later on. The results might therefore not be generalizable to children born as a single birth.

The genetic influence underlying food fussiness and food neophobia indicates that there may be common genetic variants underlying the traits. Understanding biological mechanisms behind these behaviours may aid the development of interventions to target food fussiness and new food refusal.

The fact that environmental factors also have an influence on these behaviours indicates there are ways parents may be able to modify the environment in early life to target fussy eating and refusal to try new foods.

Read more advice about coping with fussy eaters.

Analysis by Bazian

Edited by NHS Website