If you enjoy telling younger members of your family that food just isn't as wholesome as it used to be, you might need to make an exception.

Eggs are far more nutritious and beneficial for our health than they were 30 years ago, scientists claim.

Not only have they found that eggs are lower in fat, cholesterol and calories, but they also contain more vitamin D than previously thought.

A major study, funded by the Department of Health, found that the average medium-sized egg now has nearly 25 per cent less saturated fat which is linked to heart disease than one sold in the 1980s.

They contain 1.3 grams, rather than 1.7 grams. We are advised to eat no more than 20 grams of saturated fat a day.

The study also found they contain 177 micrograms of cholesterol, the substance which clogs arteries, just over 10 per cent less than the 202 micrograms previously recorded. They have fewer calories than experts originally thought, too there are 66 in a medium egg, not 78.

Furthermore, the scientists said eggs contain nearly twice the amount of vitamin D than was noted in the 1980s.

The vitamin is essential for protecting the bones and preventing rickets, a condition which causes bone deformities in young children.

But earlier this year the chief medical officer, Dame Sally Davies, warned that many of us are not getting enough of it. Cases of rickets have increased fivefold since 1997.

A medium egg contains 1.6 micrograms of vitamin D compared with the 0.9 micrograms that was recorded in the 1980s. This is two-thirds of our recommended daily amount.

Nutritionist Cath MacDonald said: 'This is a very welcome finding at a time when there is rapidly accumulating evidence that a lack of vitamin D could be a risk factor for a number of chronic diseases.'

Scientists from the Institute of Food Research believe eggs are healthier largely because the food given to hens has changed.

Since the 1980s they have been fed a mixture of wheat, corn, vegetable oil and high-protein formulated feed, rather than meat and bone-meal.

This means their eggs have less cholesterol and saturated fat. The new feed also helps them to absorb more vitamin D and other nutrients

Better technology also means scientists can now analyse the nutritional content of eggs more accurately. Previous measurements may have overestimated fat and cholesterol levels.