An egg

Eggs could protect against heart disease, cancer and eye problems, says a new study disapproving the assumption that eggs were bad for cholesterol levels.

Bruce Griffin of the University of Surrey analysed 30 egg studies and found that people who consumed one or more eggs a day were at no more risk of suffering from cardiovascular disease than non-egg eaters, reported the online edition of Daily Mail.

Egg yolks contain cholesterol, but nutritionists now know it is the saturated fats in food, not dietary cholesterol, that raises blood cholesterol levels, a risk factor for heart attacks.

"To view eggs solely in terms of their dietary cholesterol content is to ignore the potential benefits of eggs on coronary risk factors, including obesity and diabetes," Griffin says, describing eggs as super food.

One egg provides 13 essential nutrients, all in the yolks. It contains the nutrients lutein and zeaxanthin, which could help to prevent or even reverse the age-related eye problem macular degeneration (MD).

Egg whites contain albumen, an important source of protein, and no fat, the researchers say.

Eggs are an excellent source of B vitamins, which are needed for vital functions in the body, and also provide good quantities of vitamin A, essential for normal growth and development, the researchers said.

An egg's vitamin E content protects against heart disease and some cancers; there's also vitamin D, which promotes mineral absorption and good bone health.

Eggs are rich in iodine, for making thyroid hormones, and phosphorus, essential for healthy bones and teeth.

Girls who eat an egg a day in their teens may give themselves additional protection against breast cancer in later life.

It is the essential nutrients in eggs, such as amino acids, vitamins and minerals that may be responsible for this protection.

Eggs are also low in calories - a large egg contains only 75 calories and 5 grams of fat - and other research suggests they can help you lose weight.

Health experts used to recommend a maximum egg consumption of three a week to avoid a rise in blood cholesterol levels. But since evidence has shown that it is saturated fat intake that affects cholesterol, advice has changed.

Now Britain's government's Foods Standards Agency (FSA) says there is no limit as long as they form part of a healthy, balanced diet.