From the Spectator article.
"Sian Porter, a consultant dietitian, warns that ‘if people do not plan really carefully for substitutes for food groups then you can end up malnourishing yourself.’ So these diets are not simply a silly fad that might leave you a little skinnier. The pursuit of wellness and ‘clean eating’ could, in the long-term, make you unwell. ‘Often, these people have found that an approach works for them, and that’s great,’ says Porter. ‘But it doesn’t mean that it will work for anyone else"
Clearly Sian's weight loss is a work in progress. What's that I hear, don't be cruel. OK maybe so, but so is promoting high sugar and high carb products as healthy foods. Check out Sian flogging margarine, while working for the Fat Panel and potatoes for the Potato Council here.