LONDON - On one side, they're promoted as one of the best possible sources of protein, a near perfect food that can even prevent breast cancer.

On the other, they're condemned as a potential killer, partly responsible for Canada's high heart attack and stroke rates.

A fierce debate has broken out over the egg and the gloves are off between a London scientist and Canada's $800-million egg industry.

"The only Canadians who should eat eggs regularly are those with a terminal illness," said Dr. David Spence, a Robarts Research Institute scientist and director of the Stroke Prevention and Atherosclerosis Research Centre in London, which treats more than 6,000 patients.

His comments have received national attention and a strong rebuke from the nutritionist from the Egg Farmers of Canada.

"It is certainly disappointing to hear Dr. Spence's comments because it continues to support the misinformation out there about eggs," said Kim Kesseler.

"There is a whole body of research from the last 30 years showing that people can eat eggs every day without having to worry about cholesterol and heart disease."

That's propaganda, said Spence.

"If you repeat half truths often enough, they take on the colour of truth," he said.

Both sides in the bitter food fight rely on the same health studies for ammunition, especially a 1999 Harvard School of Public Health study that found participants who later developed diabetes and ate one egg a day doubled their risk of coronary heart disease compared to participants who ate only an egg a week.

But the researchers concluded consumption of up to one egg a day is unlikely to have a substantial impact on the risk of a stroke or coronary heart disease among healthy men and women.

The apparent increased risk for diabetics "warrants further research," they concluded.

Kesseler says that shows healthy people don't have to worry about eating an egg a day.

Spence says the damage in diabetics indicates eggs pose a health risk for other people with coronary health problems.

Spence's distaste for eggs is based on the amount of cholesterol in the yolk -- 275 mg. That's more than the daily intake of cholesterol in the diet recommended by the American Heart Association.

Asked if there's any health risk in consuming eggs, Kesseler's said: "Not at all."

While Spence advocates people discard egg yolks, he said consuming egg white is a healthy source of protein. He recommends it to his patients.

How are consumers supposed to sort out the debate?

Kesseler recommends they look to the Heart and Stroke Foundation and its Health Check program that endorses egg consumption.

One of the Heart and Stroke Foundation's researchers, listed on the foundation's website, is Dr. David Spence, a recipient of a $100,000 research grant.

Spence suggested people look at the individuals making the egg arguments.

"Who would you want to believe -- the dietitian who works for the Egg Farmers of Canada or a doctor who has spent 30 years trying to prevent strokes? I don't have any interest in this at all, but they certainly do. They are selling eggs, I am selling stroke prevention," he said.

For people looking for other sources of egg advice, there's the World Health Organization, the public health arm of the United Nations.

Its advice: "If intake of dairy fat and meat are controlled, there is no need to severely restrict egg yolk intake, although some limitation remains prudent," it advises.

John Miner is The Free Press health reporter. john.miner@sunmedia.ca