Novelist Fay Weldon’s famous advertising slogan for eggs back in the last century is being revised again.

Despite worries about cholestrol, nutritionists are now saying that eggs are one of the most nutrient-dense foods and are suggesting we need one a day for optimum health.

The study, which has been released today and will be published in June in the science journal Nutrition and Food Science, analyzed 71 research papers and documents about eggs.

Eggs are low in calories and a rich source of protein. They contain nutrients essential to good health, like vitamin D, vitamin B12, selenium and choline. They have the richest mix of essential amino acids of any other food.

Antioxidants in eggs could help prevent age-related macular degeneration, a leading cause of blindness, especially in the elderly.

Dietician, Dr Carrie Ruxton, said: “The health benefits of eggs would appear to be so great that it’s perhaps no exaggeration to call them a superfood — they are one of the most nutrient-dense foods available. Eggs are not only low in calories but are packed with nutrients that are essential to healthy living. They are an ideal food at every stage of life, as well as being easy to cook and enjoyable to eat.”

Eggs are an important dietary source of vitamin D. One egg provides more than 20 percent of the recommended daily allowance. Low levels of the vitamin have been linked with medical conditions, including poor bone health, cancer, heart disease, multiple sclerosis, immune disorders and mental health problems.

Dr Ruxton said, “There are clear nutritional benefits to eating eggs on a regular basis. Emerging evidence suggests that eggs may be beneficial for satiety, weight control and eye health. With previous limits on egg consumption lifted, most people would benefit from a return to the days of going to work on an egg.”

The work was funded by the British Egg Industry Council.

In a counter-intuitive article in the New York Times, which quotes researchers in Germany and Boston, exercise and antioxidants don’t mix. “If you exercise to improve your metabolism and prevent diabetes, you may want to avoid antioxidants like vitamins C and E.”

Dr. Michael Ristow, a nutritionist at the University of Jena in Germany, said, “If you exercise to promote health, you shouldn’t take large amounts of antioxidants. … antioxidants in general cause certain effects that inhibit otherwise positive effects of exercise, dieting and other interventions.”

It seems that exercise encourages muscle cells to metabolize glucose by combining carbon atoms with oxygen. In the process, highly reactive oxygen molecules are released which then attack various parts of the body damaging the tissues.

The Jena team found that in the group taking antioxidant vitamins, like vitamins C and E, there was no improvement in insulin sensitivity and almost no activation of the body’s natural defence mechanism against oxidative damage.

Once again, what we thought was done and dusted has been called into question by more research.

However, the advice does not apply to fruits and vegetables, Ristow said, even though they are high in antioxidants, it may be that other substances they contain outweigh any negative effect.

Andrew Shao of the Council for Responsible Nutrition, a trade association of dietary supplement makers, said, “I wouldn’t change recommendations for anyone based on one study. This is one small piece of the puzzle.”

The amount of oxidative damage increases with age, and according to one theory of aging it is a major cause of the body’s decline.

The findings appear in this week’s issue of The Proceedings of the National Academy of Sciences.

John Evans

Most of us know that our nails can tell us a lot about our state of health. But do we know how?

Charlotte Vohtz nails the subject in her book, Naturally Gorgeous, Essential Health and Beauty Secrets.

Here are eight tips from the book.

1. White spots or flecks on nails indicate a zinc deficiency, which may have many causes — too much alcohol or even side effects from taking the contraceptive pill.

2. Ridged or brittle nails may highlight a calcium deficiency or lack of vitamin A.

3. Cracked or broken nails — in the absence of any other reason such as heavy manual work — may show up a lack of fluids. Dehydration can cause many conditions including blocked sinuses.

4. Nails which split easily may indicate a lack of fatty acids in the diet.

5. Dryness and very rounded and curved ends could be a lack of vitamin B12, which may be linked to an iron deficiency.

6. For super-healthy nails make half your diet consist of fresh fruit and vegetables, some raw. This will boost your intake of vitamins, minerals and enzymes.

7. Add foods rich in sulphur and silicon, like fish, broccoli and onions. Also foods high in biotin, such as soya and whole grains.

8. Foods like wild seaweed (kelp tablets will do), which contain iodine for the thyroid gland, an organ that plays a part in the growth of nails, hair, skin and teeth.