According to The Mirror, the reality star jetted out to Portugal to complete a 28-day juicing programme devised by a dietician – and emerged feeling lighter and healthier.
The programme was created by Jason Vale, also known as The Juice Master, and he told the newspaper: "She lost two-and-a-half to three stone in total in four weeks, living on nothing but freshly pressed juice.
"She has been doing exercise as well but not military-style. None of it is forced. Nobody can force Gemma to do anything, frankly."
Gemma, 34, was seen looking radiant and healthy at the launch of co-sat Chloe Sims' One Vlog last week, wearing a pretty maxi dress from her own The Gemma Collins Collection.
Jason told The Mirror that as well as creating a juice diet for her, he had dealt with the "psychology of addiction" to help change her eating patterns for good.
"She can have anything she wants but she doesn't want to now. She realises crisps are the cause of the problem. The need for junk food is caused by junk food. She's getting her head around that."
Gemma quit The Only Way Is Essex over the summer to focus on other projects, including expanding her successful fashion empire.
There have also been rumorus she could appear in the next series of Channel 4 show The Jump, or return to the I'm A Celebrity… Get Me Out Of Here! jungle.
Gemma quit the last series after just three days, but later revealed she'd been facing problems in her personal life that meant her mentality for the jungle wasn't right.
"I'll always regret letting the British public down," she said.
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