Sarah Ferguson has been frank about her changes to her weight and diet in the past after being targeted for her size in the 1980s.
Fergie's figure has fluctuated over the past decades that the duchess has been in the public eye. As a long-standing member of the Royal Family, prying eyes have analysed her looks since she married Prince Andrew back in 1986.
The royal experienced a significant 50lb (3.57st) weight loss and went on the record about her "addiction" to food in 2015. Sarah admitted how she ate to deal with "lies in the media" before shaping up with a healthy diet and exercise.
She said: "My addiction was food. I used it to suppress my feelings and therefore every time I went through something - a salacious lie the media might tell about me - I ate to compensate.
"I got to a point where I just couldn't bear looking at myself any minute longer. I was 190 pounds a year ago and I was miserable. You look at the top of the mountain, you think you're never going to get there."
But the Duchess of York is a dedicated fan of Gianluca Mech's ketogenic approach to weight loss, the Express reported. She previously revealed Gianluca was the key to her healthy diet that also improved her sleep and fitness.
Sarah said: "I've tried many different diets over the years, but when I heard about Gianluca Mech's work, I decided to visit the University of Padua, one of Europe's oldest seats of learning, where the research for the diet is carried out.
"I was impressed by what I heard, and the scientific evidence there is to show the benefits of a ketogenic diet and variants of it."
The Duchess said she followed this diet for 18 months and it dramatically improved her weight and health.
Gianluca revealed Sarah likes savoury food more than sweet, so she particularly enjoyed bread, pasta and pizza. He continued: "Sarah seems very happy to me. But as she herself has said to me: 'Gianluca, you have to look for happiness inside yourself, not outside.'
"I think she's satisfied with the diet, which offers pleasure without sin."
In 2016, Sarah revealed she would eat foods including tomatoes, egg mayonnaise and mandarins to stay slim. As well as changing her diet, Fergie previously spoke about personal trainer Josh Salzmann in a testimonial.
She wrote on his website: "Fitness is mind, body and spirit, Josh always says…'Free your mind and your bottom will follow'…I personally believe in listening to your body and smart training.
"Don't overtrain, and sleep and good nutrition are just as important. "All of these values have been taught by Josh to me and I personally can say I have lost close to 50 pounds, by not overtraining and incorporating the above disciplines."
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