Actress Sarah Parish had been a yo-yo dieter for years, but it was only when she reached middle age that she found a diet and exercise regimen that worked for her.
Parish was filming the first series of a BBC comedy when she realised she had to do something about her body. "I had a particularly tight skirt to wear and had already asked for Spanx, but it just wouldn't do up," she recalls. "When they finally got it on, I was bulging out of it and the bra they had got me didn't fit because I'd put on so much weight since the last fitting. The costume person said, It's OK, don't worry,' and I remember thinking, 'Oh, don't pity me!'?"
That was February 2014 and a turning point for Parish, 47, who has starred in a string of top television dramas, including Peak Practice, Cutting It and Mistresses.
"We'd been renovating a house during 2013, I was working a lot and then I lost my dad," she says. "Slightly depressed, I was drinking five cups of coffee a day and, always tired, I'd turn to sugar - chocolate, sweets and fizzy drinks and packets of crisps.
I had gone from a size 10 to a 12/14 in six months. I was exhausted.
"I knew if I kept going, I'd have a middle-aged figure - tummy spread, loose skin between the legs, cellulite. I needed another way."
When we meet at her home, an old converted pub she shares with her husband, actor James Murray, and daughter Nell, 6, Parish's 5ft 9in (175cm) frame is a small size 10. She is as stunning in real life as she looks on television, all cheekbones, long, slim legs and polished, dewy skin. The whole picture is anything but middle-aged. So how did she do it?
Middle-aged spread happens because adults lose between two and three kilograms of muscle each decade after 30. As the human body uses 35 calories to maintain half a kilogram of muscle each day and only two calories to sustain a pound of fat, this slows metabolism. Add to that hormonal changes such as reduced oestrogen (in women) and increasing stress levels, associated with the hormone cortisol, and you have a recipe for fat to gather around the tummy.
Dieting became the obvious answer for Parish, who, as a young actor working in London in her twenties, had tried a string of diets to quickly lose weight.
"The cabbage soup diet was a classic - or completely cutting out carbs, which gave you horrible breath and grey skin. At that age I wanted instant results, but since then I've learnt. I didn't want to count calories or miss out on things I enjoyed."
A few days after "skirt-gate", Parish hired a personal trainer and began working out six days a week. "We were doing high-intensity interval training [HIIT] with heavy weight training, lots of squats and dead lifts and also short, four-minute bursts of cardio."
Though it didn't take long to get "things into place again", there were still areas of fat that wouldn't shift. The problem was that while Parish was working out, her diet had stayed the same.
"Some mornings I'd have avocado and poached eggs, but on others I'd have five pieces of white toast then snack on crisps and chocolate." One study in the American Journal of Clinical Nutrition found that middle-aged people who ate the most processed foods saw their waistlines expand three times more than those who consumed the same number of calories from less-processed foods.
"I was complaining to a health-conscious friend about not being able to shift fat at the sides of my thighs, stomach and around my back and she said, 'There's someone I want you to meet'."
It was Rick Hay, an Australian nutritional therapist who now lectures in sustainable weight management at London's College of Naturopathic Medicine.
Hay's programme, explained in his new book, The Anti-Ageing Food and Fitness Plan, is designed to counter age-related weight gain by increasing metabolism. The plan cuts out all refined sugar and processed carbohydrates and emphasises protein from plant sources such as pulses and beans, as well as eggs and fish, to help build muscle lost in the middle years.
It also introduces "thermogenic" (fat-burning) spices to recipes, such as chilli, turmeric and cayenne pepper, which have been shown to increase metabolism after eating them.
After eight weeks on the diet, Parish had dropped a dress size.
Hay's plan allows Parish to have a glass of red wine a night. To keep her sweet tooth satisfied, it features snacks such as smoothies made with naturally sweetened plant protein powders, berries, spinach and greens, as well as healthy fats such as nuts and seeds to stop the energy dips that could lead to cravings for crisps or chocolate.
The plan also appealed because of its anti-ageing element - Parish didn't have to fall into the middle-age trap of choosing between a growing behind or a gaunt and ageing face.
"Rick taught me about the importance of building muscle with HIIT training and eating a diet with enough protein and nutrient-rich foods to keep skin firm," says Parish.
By emphasising foods such as berries and greens, including raw kale and spinach, which contain phytonutrients associated with better skin health because of their antioxidant content, the results were instantly noticeable.
"At first my face went dull and a little flaky, but then I started to get more hydrated, drinking more water instead of coffee, and my eyes were much brighter and my skin more plump. Now things spring back more easily than they used to."
It has given Parish new confidence in a world that can judge looks harshly. In March, she starts filming a new television drama, The Collection. "It's about the Dior New Look in fashion in Paris in the 40s, and the clothes are all cinched-in waists and huge skirts, which I adore."
This time at the costume fitting, after 12 months on Hay's plan, she was delighted.
"Everything fitted. I had these French people going, 'Oh, oui, belle.' That felt great.
"My advice to anyone exercising who can't shift stubborn fat, despite exercising, is change your diet if you want real results," she says.
The Anti-Ageing Food and Fitness Plan checklist
Eat often - three meals and two snacks each day emphasising plant proteins.
Add "thermogenic" (fat burning) spices to recipes such as chilli, turmeric and cayenne pepper, which have been shown to help increase metabolism.
Have a juice a day made from vegetables such as beetroot, celery and cucumber sweetened with apple or pear, and snack on prunes and dates, which can reduce sugar cravings. High-intensity interval training (HIIT) - you can get live online HIIT classes from Rick's book at yoogaia.com (from January 25). Cut down on red meat and chicken. Choose eggs, yogurt and fish as animal-based proteins instead. Stick to one cup of coffee a day or one glass of good red wine a night.