Simon Cowell says his vegan diet has made him a better father. Picture: AP

Simon Cowell says his vegan diet has made him a better father.

The 60-year-old media mogul has lost more than one and a half stone (about 3kg) since cutting animal products out of his diet and replacing his pints of beer for a low calorie version, and he’s now said the lifestyle change has given him more “energy”, which helps him when it comes to his five-year-old son Eric.

Speaking at the ITV Palooza, he said: “My memory’s better, my energy’s better. And when you’ve got a five year old you’ve got to be able to keep up with them because the minute they’re awake they’re all over the place. His energy is unbelievable.

“When he wakes up he’s like, ‘Daddy, daddy, daddy,’ and before he goes to sleep, ‘Daddy, daddy, daddy’. So I was conscious of the fact I have to keep up with him energy wise and someone recommended this as the way to go.

“I tried it and I stuck to it, it’s one of the easiest things I’ve ever done.”

The ‘X Factor’ boss - who has Eric with his girlfriend Lauren Silverman - will be sticking to his diet over the festive period too, despite the Christmas holidays being synonymous with indulgent foods.

Asked if he’ll continue the diet over Christmas, he said: “Pretty much so yeah. Maybe a few roast potatoes. Not only that [it is good for the environment] but it makes you feel better. It genuinely does.”

Meanwhile, Simon recently said his diet restricts him from "pretty much all the things [he] loved”, but felt it was important to do for the sake of his son.

He said: "I went to see this doctor in London. We did some tests. And then a month later he said, 'You have the worst diet I've ever met from any patient.' So I went, 'Okay, out of the smoking, the drinking, and diet, what do I have to drop?' And he said, 'The diet.' So I said, 'I'm in!'

"It was easier than I thought, and part of the reason I did it was because of Eric. I realised if I didn't sort myself out physically, I wouldn't be able to catch up with him. Because the minute he gets up to the minute he goes to sleep ... their energy, you forget, at five-years-old, is phenomenal."