What is the cardiovascular consequence of an egg? The thought struck me as I lifted a forkful of kedgeree towards my lips. What would it do to my arteries, the quivering portion of white and golden yellow half-buried among the rice and fragrant fish?

I looked at my loving partner, suddenly suspicious. She knew my family history of heart disease and yet she had prepared a breakfast filled with boiled eggs. I suggested that perhaps she had put the eggs in by mistake. She parried with a discussion of the Anglo-British history of kedgeree. But I was unflinching. Eventually we got to the real point.

The Nurses' Health study tracked more than 80,000 women for more than 14 years. People who ate more eggs were found to be at no increased risk of heart disease or stroke. And a similar study of 40,000 men found the same thing.

Of course, observational studies can be treacherous. People who eat more eggs may not be similar to people who eat none. If people with family histories of heart disease avoid eggs, for example, observational studies could falsely make eggs appear safe.

But the Nurses' study is no aberration. A paper in the American Journal of Clinical Nutrition systematically combined everything the human race had learned about the experimental effect of eggs upon concentrations of fats in the blood. A standard egg was found to raise the heart disease-causing form of cholesterol (LDL) by a meagre 0.1 millimole per litre. At the same time it increased the health-giving HDL cholesterol by only 0.02. "Those numbers," said my partner, "are clinically trivial. The apparent risk to your health from an egg is so small that only a fool would pause to think of it." That told me.