Atkins diet affects cholesterol while Zone diet more easily follows healthy diet principles, researcher says

Otago University Professor of Nutrition Jim Mann, who heads what is believed to be a world-first, long-term direct comparison of Atkins with two other popular diets, is concerned about its effects on cholesterol.

He has spent a year monitoring 100 Dunedin women on either the low-carbohydrate, high-fat Atkins diet, the low-carbohydrate Zone diet, and a high-carbohydrate, high-fibre eating regime.

His six-monthly findings on health effects are being written up for publication by an international medical journal and cannot be divulged.

Mann said his clinical experience showed some patients' cholesterol levels rose significantly while on the fatty Atkins diet.

"That's a huge worry," he said. "While the Atkins diet encourages saturated fats – which puts up cholesterol, increases resistance to the action of insulin and has a tendency to make blood clot more – it is not something I will be recommending."

Atkins diet devotees should have their cholesterol carefully checked, urged Mann.

People were attracted to the diet, founded by the late New York cardiologist Dr Robert Atkins, because it achieved rapid weight loss initially.

"Anything that gives you short-term weight loss will capture the imagination, because there are so many people wanting magic bullets," he said.

"But most of the people I know who have gone on it cannot sustain it. They hate it after a time and are delighted to be off it."

Previous research had shown that the Atkins's effectiveness after a year was no different to other approaches.

Mann said Wigram MP Jim Anderton boosted the popularity of the Zone diet – which has above-average protein and fat and low carbohydrate.

Anderton reportedly lost about 8kg in three months on the 1999 campaign trail.

"The Zone diet can more easily follow healthy diet principles," said Mann.

"You can reduce carbohydrates but still have a reasonable amount. You can have protein that is not too fatty and the right kinds of fats."