Ella is doing much better at school since starting the diet
A UK trial has for the first time shown a ketogenic diet can reduce fits in children with epilepsy, compared with standard treatment.
The results prompted the researchers to call for wider availability of the diet on the NHS.
Rachel Farrand, 38, from Redhill in Surrey, says she feels incredibly lucky to have been able to get her six-year old daughter, Ella, on to the diet.
Ella was a healthy baby until the week before her first birthday, when she was
admitted to hospital with pneumococcal meningitis.
The infection left her profoundly deaf and, although she was fitted with a cochlear implant to restore her hearing, it became obvious she also had learning difficulties.
She also started to have seizures - where her arms would extend and stiffen - and just over a year after her meningitis she was diagnosed with epilepsy.
The seizures seemed to happen after the sudden appearance of people and objects - literally when Ella was startled - and she would quite often fall to the ground.
She would be dazed afterwards and if a few fits happened close together she would need to have a sleep.
An EEG of the brain showed her brain waves were "very abnormal", Rachel explained.
Anti-epileptic drugs did nothing to control her symptoms and turned her into a "zombie".
Shortly after her fourth birthday, the seizures stopped and Ella was able to concentrate and was much more interested in what was going on around her, as well as responding to sounds.
But after a few months the seizures came back and, having seen the difference in her when she was seizure-free, her parents decided to try the ketogenic diet.
Ella has to eat three-and-a-half parts fat to every one part protein and carbohydrate.
She has three strictly-controlled meals and two snacks a day, which all have to be measured to be the correct ratio and the correct number of calories.
"Within days she seemed calmer and began sleeping better," says Rachel.
"Her concentration and focus improved and once again she was like a different child."
A TYPICAL DAY'S FOOD
Breakfast - mushroom omelette, small bowl of raspberries and clementines, and a hot chocolate
Lunch - thai stir fry with quorn, courgette, onion and peppers and a strawberry milkshake
Dinner - roast chicken with cabbage, broccoli and carrots, small bowl of strawberries and vanilla ice cream
Snacks - ketogenic coconut cookie (with ground almonds instead of flour), ketogenic chocolate (plain chocolate mixed with creamed coconut)
After six weeks on the diet her seizures stopped and tests showed her brain activity was much calmer.
"It's tricky at first but once you get in the swing of things it's fine.
"I can now make up a ketogenic meal quite quickly, it's just become a way of life."
The family make sure they do not snack in front of Ella, and her younger brother Alfie is adept at having "sneaky snacks" out of view of his sister.
Ella's parents were able to wean her off her remaining anti-epileptic drugs with no adverse effects.
"She continues to be hard work, and her progress will always be slow and erratic, but losing the seizures means we have one less thing to contend with," Rachel says.
Recently Ella was diagnosed with premature puberty - another result of the meningitis - and as a result her seizures started to come back, although they are much less severe.
Rachel hopes they will be able to get back on track soon.
"We're still seeing such improvements and when we took her off the drugs we saw the little girl underneath - she's much brighter and sparkier.
"We were so lucky - people fight for years to get their children on the diet. Hopefully with this research the NHS will put more money in."