The star, who has allegedly lost three stone, told The Sun that his slimmed-down physique is down to "healthy eating and drinking tonnes of water." Simon also credited his weight loss to cycling on his e-bikes – which he has 15 of in his Californian mansion.
WATCH: Find out how Simon Cowell picked up his e-bike injury
Even an accident that left him in a back brace couldn't deter Simon from exercising on his electric bikes, though not everyone believed his weight loss was down to cycling, with rumours rife that the 62-year-old had a gastric band – something that the music mogul denies.
"I did see a doctor in Harley Street. He specialises in a certain kind of diet," Simon told The Sun. "He did my blood work and pee and all the rest of it, and a month later the results came in and his words were, ‘You have the worst diet out of all the clients I have ever seen in my life — you have a schoolboy's diet from the 1960s.'
"It was just pies. So he sent me a list of things I can't eat, and that included red meat, dairy, sugar and gluten. And I pretty much stuck to it."
Simon rides his electric bikes for exercise
Simon shared that his daily diet consists of a green smoothie and no-sugar Alpen, with tea and oat milk for breakfast, followed by a lunch of grilled tomatoes and soup.
In news that will horrify foodies everywhere, Simon admitted he often goes out for dinner and opts not to eat.
Simon opts not to eat when he and partner Lauren Silverman go out
"I'm not a big eater," he told The Sun. "I don't enjoy it that much. I'd rather have a beer than eat, any day of the week.
"Sometimes when we are going out for dinner because I know I'm going to hate the food, I have baked beans on toast before I go, then eat nothing."
We don't encourage people to copy Simon's diet and a balanced approach is best when it comes to health and fitness.
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