Mann told the Herald he was extremely concerned people who trust him may be misled by these advertisements in a way that could adversely influence their health.
He first became aware of the manipulated video on Monday morning when he received a text message alerting him to its existence.
“That was really the first time I saw it. And then I was just bombarded after that with texts, emails from two groups of people ... One [group was] saying, ‘Congratulations on this wonderful new product ... that you’ve discovered and great that you’ve exposed all these medics and other people as being frauds ... where can I get the product?’ And other people who said, ‘For goodness sake, be aware, you’ve been scammed’,” he said.
The widespread belief in the video was deeply troubling, he said.
“There were some really very reasonable, intelligent people who had completely taken it, including people that I know well ... Goodness knows how many people have been taken in.”
The video was temporarily removed from Facebook, but Mann said it has resurfaced several times.
“AI is so clever that they could manipulate my mouth to be looking as if I was saying those words.
“It makes me feel terrible because I’m patron of Diabetes New Zealand, so a lot of people are aware of my name, even if they don’t know me.”
Mann urged caution to those who encounter seemingly too-good-to-be-true statements online.
“If you hear somebody saying something that sounds too good to be true, it probably is too good to be true ... They were pretty outrageous claims.”
The university and law enforcement are continuing to investigate the case, and Mann hopes his experience serves as a warning about the dangers of AI-powered misinformation.
While some people identified the video and story as a scam, many others believe it and have even asked him where they can buy the product.
Mann encouraged people to source reliable information from Diabetes New Zealand or recognised health professionals.
Vice-chancellor Grant Robertson said he was disappointed that Mann, a leading authority on diabetes who is widely respected for his knowledge on the topic worldwide, is the target of a scam, spreading misinformation.
“Sir Jim has dedicated his career to helping people. To have his reputation taken advantage of and his likeness used for nefarious purposes is highly distressing,” he said.
Deepfakes utilise artificial intelligence to copy people’s likenesses on to videos and image, and are often used in misinformation and scam content to mislead victims.
The New Zealand Police and Netsafe websites contain information on scams, information about how to identify them, and where to report them.
While frustrated at the situation, Mann said he felt sympathy for those who had been misled.
“All I can say is, I’m really sorry that it happened, even though it was totally beyond my control, that my name ... was used in this way,” he said.
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