It's the supplement with Hollywood endorsement - but what impact is collagen having on the health of the planet?
An investigation involving ITV News can - for the first time - link a health supplement sold in shops like Boots and Holland & Barrett to deforestation in Brazil.
Bovine collagen powder is all the rage among "wellbeing" influencers.
One brand, Vital Proteins, is promoted by the likes of Jennifer Aniston, Georgia Toffolo and Mark Wright.
In adverts on their social media accounts, they claim adding scoops of the white powder to food and drink can improve the health of your skin, hair and joints.
Our investigation in conjunction with The Bureau of Investigative Journalism, the Guardian, O Joio e O Trigo and the Pulitzer Center’s Rainforest Investigations Network has traced the supply chain of cattle used to produce collagen - to meat processors in Brazil, which have been repeatedly linked to illegal deforestation and the invasion of indigenous lands.
ITV News' Health and Science Correspondent Martin Stew explains the links between deforestation and collagen
Collagen is listed as a by-product of the beef industry. As a result, it’s often subject to less scrutiny than beef which ends up in the food chain.
“Fresh beef products exported to the EU have to be traced back to a ranch of origin,” said Chris Moye from the Environmental Investigation Agency.
“The same doesn’t really apply to the by-products. You will never know, therefore, where it comes from.
"That’s the bone of contention that’s where most of the deforestation in the Amazon is found.”
The wider cattle industry is linked to thousands of square kilometres of deforestation each year in Brazil.
Over the past 30 years the land around the Mae Maria reserve has turned from lush forest to dry ranches
Indigenous people say their protected land is “being surrounded, suffocated on an island.”
The leader of the Gavião people told us farmers “destroy what is theirs, and invade what is ours. I can't understand why they destroy everything.”
They also claim illegal methods are being used to encroach on their land.
“We had a whole village burned down,” volunteer firefighter Aiteti Gavião said. "Most of the fires here in the indigenous land are arson.
"This is what happened here in the reserve, where a whole village lost homes, people lost their belongings, even animals were also killed because of the fires.”
'Even animals were also killed because of the fires'
It’s likely many collagen companies use similar supply chains to Vital Proteins, which is owned by Nestle.
It told us “allegations raised are not in line with its commitment to responsible sourcing and that it has contacted its supplier to investigate this matter.”
It added that it is “taking steps to ensure its products are deforestation-free by 2025."
Both Holland & Barrett and Boots say they are now talking to suppliers to make sure products are responsibly sourced. There’s no suggestion celebrities knew of the links to deforestation before posting ads.
We approached Georgia Toffolo, Michelle Keegan and Mark Wright for their reaction - they all declined to comment. Jennifer Aniston, who is Vital Proteins' Chief Creative Officer, referred us to Nestle’s response.
Photographer/videographer: Cícero Pedrosa Neto and Aiteti Gavião
Collagen Explainer Graphic: Jules Bartl
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