Keeping Lucy away from goodies makes for a calmer household, her mother Maria Dollard tells Fiona Murdoch

Much of the food in the kitchen of Maria and Niall Dollard's home in Kilkenny is kept under lock and key. Bread, biscuits, chocolate and sweets are all in a locked cupboard and when brothers Brian (11) and Jim (4) want a snack they have to ask Mummy for the key.

Lucy, their eight-year-old sister, however, is never allowed the key because she is banned from eating any of the food kept in the cupboard. She was diagnosed with autism just before her fifth birthday and is sensitive to many everyday foods.

Although the gluten-free and dairy-free diet she has followed for the past three years is restrictive she can eat meat, fish, potatoes and rice as well as fruit and vegetables.

Breakfast cereals are out, but there are gluten-free versions of rice crispies, cornflakes and porridge that she enjoys. Sandwiches for lunch never present a problem since Mum buys gluten-free bread and dairy-free margarine. And Lucy simply loves jam and peanut butter sandwiches!

She also loves the gluten-free spaghetti bolognese and meatballs Mum often makes for dinner. Like most children, though, she is not too keen on vegetables. But Mum has found a clever way of getting her to eat parsnips. When chopping up potatoes to make chips, she chops up the parsnips, too, and bakes them all together making Lucy think the parsnips are delicious chips!

The whole family enjoys eating dairy-free ice-cream for dessert - Mum never buys the ordinary variety because she has no way of locking the freezer.

"Sometimes Lucy and Jim get into cahoots together on a Saturday morning," she says. "I'd come downstairs and find them sitting on the sofa watching TV with a tub of dairy-free ice-cream between them - with a spoon each. I just laugh when I see them!"

Luckily, Lucy does not miss out on family trips to McDonald's. She can eat the burger without the bun and she can have chips and Coke. The biggest restriction involves sweets and chocolates. She can eat Bourneville, Fry's chocolate cream and special dairy-free chocolates, but most sweets are out because they contain monosodium glutamate.

"Christmas is always a nightmare because everybody always comes to the house with a box of chocolates," says Maria. "It's so hard on her: she knows she can't have any.

"It's not really fair on the boys either because they have to hide their sweets here, there and everywhere so she can't get them. They are trained not to leave bits of bread lying about: if she found a piece, she would pick it up and eat it." Whenever Lucy breaks the diet, her mother soon knows from the changes in her daughter's behaviour: she becomes less responsive and more sensitive and touchy.

"Before she started the diet, you couldn't touch her because she was so sensitive," says Maria. "And the pupils of her eyes were always dilated as if she was on drugs. Whenever she ate chocolate she'd be swinging from the lightbulbs and laughing her head off."

Mum is delighted with the progress her daughter is making. She attributes this to the diet, the megavitamins she imports from America and the "great work" of the School of the Holy Spirit that Lucy has attended for the past three years.

"Her speech and language have really improved. She still has autism - there's no doubt about that - but all the ancillary symptoms, like flapping her hands and jumping up and down and the vacantness of her condition have all improved.

"Whereas before I had to call her three or four times before she'd respond, now I just need to call her once and she comes straight over to me. It's like some of the fog has cleared."

This is fantastic not just for Lucy, but for the whole family: "When Lucy's in good humour and having a good day, we're all high as kites. But if she's having a bad day - particularly if she breaks her diet - she becomes very touchy and jangles our nerves."

"By accepting what I can't change - her autism - I can focus all my energy on improving things for her, like keeping her on this diet."

The Irish Society for Autism may be contacted on (01) 8744684