A leading public health physician is warning the ABC not to air a second program on cholesterol, saying it could result in deaths.
Last week Catalyst claimed the notion that saturated fat and cholesterol causes heart disease is the biggest myth of medical history.
This Thursday's program is about anti-cholesterol drugs known as statins, which are widely used in Australia.
The chair of the Advisory Committee on the Safety of Medicines has written to the ABC in a private capacity, warning the program might cause people not to take their drugs.
Professor Emily Banks says that will lead to more cardiovascular disease events and deaths.
"If people stop using their statins or if they don't start them when they should be, it's very likely that it will result in death," she said.
"It's likely that if this program goes ahead, and it does the unwarranted undermining of statins, that there will be people who didn't have to have a heart attack and didn't have to die from a heart attack, who will die through reducing use of statins."
Thursday's scheduled program is the second in a two-part series. Promotions say it examines how the benefits of statins have been exaggerated.
Professor Banks is highly critical of last week's program, which claimed the science linking cholesterol with heart disease is not as conclusive as widely thought.
"We have overwhelming evidence from studies of over 900,000 participants showing a strong and graded increase in the risk of heart disease with increasing cholesterol levels," she said.
"But what we saw on Maryanne Demasi's report, was a series of anecdotes from, I think what would be broadly termed fringe-dwelling scientists or people who weren't actually scientists, criticising things about the cholesterol myth.
"But actually it's one of the relationships that we have the strongest evidence for."
Professor Banks admits she does not have a lot of detail about this week's program, but says she understands it is the same journalist.
"I suppose my concern is that I've already seen what that journalist has said, and the way the journalist has dealt with it on the first Catalyst program," she said.
"And all I can say is that I am afraid that there will be a similar treatment of the statin issue in the coming program.
"I understand that the target this time is about use of statins for prevention of heart disease," she said.
"And I'm just going on last week's show - which really said that cholesterol was a myth, which is clearly incorrect - that there's going to be some similar treatment of use of statins."
The series producer of Catalyst, Ingrid Arnott, told PM the program stands by its claims and has research to back them up.
She also says this week's program is asking questions but not telling viewers to stop taking statins.
Doctor Steve Hambleton, the president of the Australian Medical Association, thinks the program should go to air.
"I think we have to have a debate. And I think that there needs to be balance," he said.
"We need to, as medical professionals, justify why we choose drugs. We do criticise others for not acting on evidence. We need to be judged by the same criteria.
"So if there's a good reason to take it, we should be able to explain it, and we should be able to explain the risks and the benefits of any treatment."
PM asked ABC TV if the program will air as scheduled on Thursday.
A spokesman says it will, and that it is an important contribution to medical debate.
The program will include a note advising viewers it is not intended as medical advice.