The scientist leading the campaign for a massive reduction in the nation’s sugar intake has admitted it had resulted in “hysterical” and “exaggerated” headlines about sugar.

Professor Graham MacGregor, chairman of Action on Sugar, also described some anti-sugar campaigners as “nutters”. But he claimed sensationalist headlines in the national press – despite often lacking scientific evidence – had served a purpose because they had forced politicians and businesses to “sit up and do something”.

“We don’t encourage the hysterical headlines, but it’s good for us because it’s the only thing the government responds to,” he said. “We don’t make these exaggerations. It’s been whipped up by other people. Some people like the Food and Drink Federation think we’re morons but we are not the ones going around saying that sugar is to blame for everything.

“Clearly we would like more to be done on satfat and salt. We are not saying that it is all about sugar and that it should be removed completely from the diet, but there are some nutters out there claiming that if you go sugar-free, you will get a new life or you will find Jesus.”

The Action on Sugar campaign has its fair share of controversial characters. Its global expert advisor Dr Robert Lustig has labelled fructose a poison and science director Dr Aseem Malhotra described the threat posed by satfat in the diet as a “myth”.

Meanwhile, one of its non-medical advisers Tam Fry, a spokesman for the National Obesity Forum, admitted last month in The Grocer that its claims of an obesity “doomsday scenario” were based on “no statistics” and “no evidence”.

MacGregor said health campaigners had decided the only way to get action was to go along with the headlines.

This week, the Daily Mail quoted him as saying a series of what it described as “secret stitch-up” meetings between the food industry and government ministers had been a “scandal,” though The Grocer revealed they were mostly scheduled meetings relating to pledges made under the Responsibility Deal, with health NGOs also present.

“The Daily Mail exaggerated that a little bit,” he said. “The meetings are irrelevant, unless there is some sort of conspiracy, which I don’t think there has been. The fact is that it is the Responsibility Deal which is a bonkers idea and needs to be replaced with a return to the old FSA-type system with proper targets.

“The food industry is much more reasonable than it has been painted out to be. In fact speaking to the BRC it’s clear they would rather this was the approach rather than persisting with the Responsibility Deal, which isn’t working.”

This week, dozens of nutritionists took part in a heated Twitter debate on the role of sugar in the diet. Nutritionist Sasha Watkins, who hosted it, said: “Sugar has become the culprit of the moment but the overriding view was we should be very wary of blaming one particular ingredient for the obesity crisis.”

Diabetes UK tweeted: “Foods that are high in added sugar may be high in calories but total nutrient content is more important.”

“I think media articles that point out how much sugar some foods contain, while sensationalist, might encourage people to check labels,” added Sarah Schenker, a public health nutritionist.