McAloon worked for Paltrow and her then-husband Chris Martin while the actress was filming "Iron Man" in 2008.
"I had a brief from their assistants ... they eat nothing," McAloon divulged to News.com.au. "They are very strict. They avoided any sugars, anything sweet, no dairy, just more vegetables."
Speaking bluntly, the celebrity chef added, "When I got there I was trying to stick to the brief and I realized as I started adding more ingredients in, they said 'Your food is getting better.' That's what happens when you eat more than grass."
McAloon has cooked for a number of high-profile celebs, including Steven Spielberg, Courtney Cox and supermodel Miranda Kerr. While every client has their own dietary restrictions, it seems the 59-year-old chef had the most difficulty sticking to Paltrow and Martin's strict meal regimen, noting that even Kerr followed a more forgiving diet.
"She has the 80/20 rule that she sticks to," McAloon said of the Victoria's Secret model. "So eating healthily 80 per cent of the time and having a treat the other 20 per cent."
McAloon did not comment on whether or not Paltrow and Martin's two kids, Apple and Moses, followed the same diet as their parents when she worked for their family. At that time, the children were only four and two years old, respectively.
In 2013, Paltrow revealed that she tries to keep her kids on a low-carb, gluten-free diet, but just last year, she supposedly changed her attitude regarding food.
"Their favourite foods are pasta and French fries," she said of her kids. "It's about trying to augment that with something healthy."
Paltrow has also relaxed her attitude when it comes to her own diet. Earlier this year, she told Shape, "Usually, I just try to eat pretty clean during the day — good proteins and lots of vegetables and not too much grain or sugar, and nothing baked — and then I tend to eat whatever I want for dinner."
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