Fussy eaters can be a nightmare for parents even though most children usually grow out of their picky food habits.
But for a few with a newly diagnosed eating disorder, every meal can seem like a plate of raw liver, so disgusting sufferers want to vomit at the sight of it.
Avoidant Restrictive Food Intake Disorder (ARFID), was defined four years ago and is so new little research has been done into treatment. But a documentary called The Secret Lives of Fussy Eaters is attempting to lift the lid on the problem.
Many sufferers are children whose dislike of food and lack of appetite has grown steadily worse instead of better.
The disorder is so serious one New Zealand sufferer has begun to go blind because of the extensive and debilitating effect of malnutrition, caused by a compromised diet, on his growing body.
Jake Thompson's food revulsion is so severe it has almost killed the Greymouth teenager.
From the age of three, Jake - like most other ARFID sufferers - has only been able to eat very dry, mostly yellow food, such as chips, white bread and chicken nuggets.
Although every case is unique, ARFID sufferers largely do not eat fruit, vegetables, dairy products, and most meat.
Because Jake's severely restrictive diet has continued for more than a decade, the 18-year-old's body is ruined.
New Zealand Eating Disorders Clinic registered psychotherapist Kellie Lavender said there is a difference between relatively normal fussy eating in children, and ARFID.
"This is fussiness to the extreme where there are physiological growth issues, significant medical problems... and their psychosocial functioning becomes very interfered with."
Eating out socially in any form, whether it's school camp, a play date or at a restaurant, "becomes very distressing".
Where up to 30 per cent of children are fussy eaters, early studies have indicated between and 5-10 per cent of people suffer from ARFID, with patients sick longer than anorexia sufferers and with a higher proportion being males.
Despite the presentation of the psychiatric illness being around for many years, a diagnostic manual was only first published in 2013 by the American Psychological Society.
Lavender said most children she sees are aged between nine and 11 and their parents have usually been concerned for years.
However, she said the food phobias can be overcome and sufferers can lead a relatively normal life with the right treatment.
ZM drive host Jase Hawkins confesses to being a picky eater in the documentary.
Hawkins said he has disliked all cold food including salads, fruit and cheese since he can remember.
"I'll eat a toasted cheese sandwich but I won't eat a cheese sandwich. I love meat but I won't eat it cold. Antipasto would be my idea of hell."
As the 35-year-old reached primary school age his anxiety around the phobia began to intensify, so much so that he would not go on school camp just to avoid situations where he might be harassed for not eating certain foods.
"When you're a kid trying to fit in, I would have massive anxiety if we were going to group dinners or school camp, I would freak out."
These days Hawkins said he is much more open about his phobia and his family, friends and colleagues work around it.
Lavender said one trick for dealing with a fussy eater is to help them tolerate foods.
"[Parents can say] 'I don't expect you to like it, but you have to learn to tolerate it for the sake of health.' Often that's where people get tripped up. People say 'Well my child doesn't like it' but that might not be the goal."
She said a disliked food can be introduced alongside accepted food and eaten together.
Lavender said parents would recognise the difference between a fussy eater and a child who is potentially suffering from ARFID.
"It has a level of refusal and fear associated to it that is just not normal."
Tips for parents of fussy eaters:
• remain consistent and persistent
• avoid anxiety-provoking environments
• be patient and compassionate.
The Secret Lives of Fussy Eaters - tonight, 7:30pm on TVNZ 1.