Twin study of fussy eaters reveals new clues

Parents are not to blame for “fussy eating”, researchers say, as a large study suggests fussy eating tendencies are mostly down to genetics rather than parenting styles.

And the tendency to be fussy over food can persist into early teenage life, the team says, building on their previous work looking at toddlers.

The UK study compared the eating habits of identical and non-identical twins from 16 months to 13 years old to tease out how much is due to genetics and how much to the environment.

Identical twins were much more similar in terms of how fussy or adventurous they were with food than non-identical ones – suggesting a strong genetic component.

But strategies to help increase the variety of food children eat – including offering a range of foods – can still be helpful, particularly in early childhood, they say.

The work appears in the Journal of Child Psychology and Psychiatry.

Professor Clare Llewellyn, senior author on the study at UCL, told the BBC Radio 4’s Today programme: “The reason why some children are quite ‘finicky’ with trying certain sorts of food and others are more adventurous and they happily join in with family meals is largely down to genetic differences between children rather than parenting styles.”

The study’s lead author, Dr Zeynep Nas, said she hoped these findings would “help to alleviate parental blame”, acknowledging that fussiness, while common, could be “a major source of anxiety for parents and caregivers”.

The team studied food survey results completed by parents of 2,400 identical and non-identical twins when their children were 16 months old, three, five, seven and 13 years old.

They focused on the concept of food fussiness – which researchers describe as the tendency to eat a small range of foods, due to selectivity about textures or tastes, or a reluctance to try new foods.

Comparing the food habits of identical twins who share 100% of their genetic material with those of non-identical twins who share around 50% of their genetics, researchers found:

• Fussy eating tendencies endured into early adolescence with a slight peak at the age of seven

• Genetic differences in the population accounted for about 60% of the variation in food fussiness at 16 months

• Genetic influences increased with age, rising to 74% between the ages of three and 13.

Factors at home – such as what types food are eaten together as a family – were found to be significant, mostly for toddlers.

As children got older, influences outside the home became more relevant, for example, having different friends.

Dr Llewellyn said while the study was not designed to look specifically at strategies to help fussy eaters, other work suggests certain techniques help, including:

• Continuing to offer a wide variety of food

• Offering food regularly that children may have rejected before. This should be in a calm environment and does not necessarily need to be at meal times

• Sitting down to eat with children if possible and trying not to get too stressed.

While so-called fussy eating can be common, excessive selective eating can be a key symptom of avoidant and restrictive food intake disorder (ARFID), a relatively recently recognised eating disorder, researchers say.

This may benefit from specialist support.

Olly from Colchester said his teenage son was diagnosed with ARFID two years ago but looking back he feels it started about 8 years before that.

“It’s so different to being fussy,” he told BBC Radio 5 live’s Nicky Campbell show.

“My daughter, she can be a little bit fussy, but if you tell her you will give her 50 pence if she eats a bit of broccoli, she’ll eat it.

“You can put half of million pounds cash in front of my son and he wouldn’t touch it.”

He said his family have helped him through it.

“They have been there with me, pushing doctors,” he said.

“This isn’t fussy eating, it’s something completely different.”

Julia from Swindon said her daughter was about two or three when she started to refuse food she had always enjoyed.

“If she put something in her mouth that she didn’t feel safe with, she wouldn’t be able to tolerate it, even when she was little,” she told Nicky Campbell.

“I didn’t know that ARFID existed.

“She just came to me one day, she said ‘Mummy, I need help. All I want is to sit and eat with you, I want to eat the same food as you’.

“That’s heartbreaking to hear.”

The work on fussy eating was led by researchers from UCL, King’s College London and the University of Leeds and funded by the UK mental health charity MQ Mental Health Research.

The study involved mostly white British households of wealthier backgrounds than the general population of England and Wales.

Future research could focus on non-western populations where food culture, parental feeding practices and food security may have differences, researchers say.