Susannah has proudly declared that she weighs less than Trinny.

Susannah Constantine was never the kind of person to have hang-ups about food or weight. As a stylist on TV phenomenon What Not to Wear, she spent years telling women how to dress for their shape, and even once famously described herself as a “frustrated page three girl” with no shame about her body.

But things changed when she reached her 40s: “That’s when it started to stick,” the Brit wrote in The Sunday Mail. “Like countless others, I thought I was immune from middle-aged spread, until I wasn’t.”

Quips from her daughter about causing the bath to overflow, an “unflattering” picture of herself in a magazine all stung. But it was being approached to participate in a charity fitness challenge called Famously Unfit… For Sports Relief, that Susannah decided to change her attitude toward health.

A post shared by Susannah Constantine (@susannahconstantine) on Mar 4, 2018 at 4:08am PST

“I told friends and family, or anyone who’d listen, that I was happy in my skin, that I was determined to defy convention. It was easier to laugh and say ‘I don’t care’, except that I did care. Very much,” she wrote.

“In my heart, I knew I was letting myself go and, worse, that I was 90 per cent of the way to the point of no return.”

Medical assessment for the Famously Unfit challenge hammered it home: “My body fat percentage was 32.7, which tipped me into the obese range, and it turned out there was too much fat caking my internal organs, also.

“I can’t say the grim reaper was hovering, exactly, but our adviser, Professor Greg Whyte, a former Olympic pentathlete, was clear: if I carried on as I was I’d be a very unhealthy old woman.”

Fresh, healthy food and exercise (five times a week) means she's diverted from that path.

But based on her Sunday Mail piece, there was another reason Susannah decided not to "carry on" with her lifestyle. And it's all there in a single proclamation: "Today I can announce that, for the first time ever, I weigh less than my dear friend and former TV ‘sister’ Trinny."

That's Trinny Woodall, her former What Not To Wear co-star.

"Trinny is a skinny size eight, it’s true," Susannah added, "but her extra inches of height mean I’m definitely the lighter of the two."

The phrase "keeping up with Trinny" is also used, and descriptions of her pre-weight loss self include "frumpy", "tug boat", "a fat hippo". Yes, she wrote the words "fat hippo" - about herself. It's the kind of negative self-talk a lot of women will find all too familiar. The comparison to a friend, the internalisation of an off-hand comment.

She continued, "I knew it was really working after yet another wry comment from [14-year-old daughter] Cece. ‘Mum you look great from behind,’ she said one morning. ‘The back flubber that used to hang over your pants has gone.’"

It's hard to see what's 'working' about that.