Diet guru Michael Mosley has explained what happened when he changed one thing in his diet - and piled on weight. The expert who founded the famous 5:2 and Fast 800 eating plans was speaking to nutrition expert Tim Spector on his podcast Just One Thing on the BBC.
The pair were speaking about the rise in ultra processed food and the huge impact it has had on the nation’s health. Professor Spector had said that the UK is in the middle of a crisis on the issue: “What people don’t realise is that as well as affecting your gut health, recent studies have show it increases your appetite and eating identical calorie meals - one home cooked the other frozen - both queally tasty - you will eat an extra 500 calories a day of the ultra processed food. And it will make you feel rotten and you don’t know why because you’ve read the packet and it says it’s low calorie or it’s low fat.”
Dr Michael Mosley said that he had carried out a test himself - he ate nothing but processed food like frozen dinners and fast food - and put on almost half a stone in just two weeks. He said: “A couple of years ago I decided to put myself on a junk food diet. I was going to do this for two weeks. I ate things like frozen meals, going out for burgers and chips and fried chicken and slurping back drinks like milkshakes.
“I managed to put on about three kilos in two weeks. My waist expanded by 3cm. But what was really impressive in a bad way was that my blood sugars went back into the diabetic range having been perfectly healthy. And my blood pressure also soared and I also developed these crazy cravings for this stuff and it really lowered my mood.”
And he revealed how he spots ultra-processed food: “I was once advised to never eat anything you can buy in a petrol station as a simple guide to what processed food is.”
Prof Spector said: “In the UK we have the highest intake of ultra processed foods in Europe and it’s not a coincidence we have the highest rates of childhood obesity and adult obesity and all these consequences. It’s been estimated it costs us about £58 billion a year in those associated health costs. On an individual level I also think it’s important to realise it’s not the fat, the sugar, the salt, that we thought it was the only thing important, it’s the processing -it’s the fact that these are fake foods. They don’t contain natural ingredients - they contain extracts of natural ingredients put together in a factory, looking like edible food substance and added flavourings.”
And Prof Spector explained that these kinds of foods can have a big impact: “They are knocking out their gut microbes. They are increasing their appetite. They’re lowering their mood. Is it really a surprise we’re such a sick nation.” He explained by making it cheaper, advertising it and having it in schools people were being actively encouraged to eat ultra processed foods.”