Good eggs: For nutrition, they're hard to beat
What would we do without the egg? It's a dietary mainstay, not only for breakfast but to feed finicky children, as a stand-in for a quick lunch or supper and an ingredient in all kinds of sweet and savoury dishes.
However, for a few decades eggs had a rather unwholesome reputation. Thanks to its high cholesterol content and the salmonella crisis in the late 80’s, the egg was deemed villainous. Years went by while many of us shunned eggs, ate only the whites or ventured into the world of egg substitutes.
Then, in 1998, the Lion mark was reintroduced to signify higher egg production standards. Meanwhile, organisations such as the British Heart Foundation and Food Standards Agency relaxed their restrictions on egg consumption for healthy people - there’s no longer a need to limit the number of eggs you eat - putting emphasis on reducing saturated fat in the diet, especially for those with an increased risk of coronary heart disease.
The confusion over eggs stems from their cholesterol content. One medium egg contains 213mg of cholesterol, accounting for two-thirds of the recommended daily limit.
When scientists learnt that high blood cholesterol was associated with heart disease, foods high in cholesterol logically became suspect. However, after further study, saturated fat is now believed to have a much bigger effect on blood cholesterol.
The British Heart Foundation’s senior dietitian, Victoria Taylor, says: "In the past there have been restrictions on the advised number of eggs people should eat in a week. This was because we thought cholesterol in our bodies was directly caused by cholesterol in our food.
"As research has developed, however, we now know that much of the excess cholesterol in our bodies is actually produced by eating too much saturated fat rather than eating too much cholesterol."
The British Dietetic Association adds: "Although some foods contain cholesterol – such as shellfish, eggs and offal – this has much less effect on our blood cholesterol than the cholesterol we make in our body ourselves in response to a high saturated fat diet."
Let us eat eggs
With science on our side, we can once again enjoy the wonderfully nutritious egg. Along with milk, eggs contain the highest biological value (or gold standard) for protein. One egg has only 75 calories but 7 grams of high-quality protein, 5 grams of fat and 1.6 grams of saturated fat, along with iron, vitamins, minerals and carotenoids.
The egg contains nutrients such as lutein and zeaxanthin. Some observational studies have suggested that people who eat a diet rich in antioxidant vitamins (carotenoids, vitamins C and E) or minerals (selenium and zinc) may be less likely to develop age-related macular degeneration (AMD), the leading cause of blindness in older adults.
However, a 2007 review of three randomised, controlled trials involving 23,099 people was conducted by researchers at the London School of Hygiene and Tropical Medicine. The aim of the review was to examine the evidence as to whether or not taking vitamin or mineral supplements prevents the development of AMD. They concluded: "There is no evidence to date that the general population should take antioxidant vitamin and mineral supplements to prevent or delay the onset of AMD. There are several large ongoing trials."
There has also been some research into the effect of choline on the brain. Choline is contained in eggs. A 2010 review of 14 relevant double-blind, randomized trials was carried out by researchers at the University of Rome. The aim was to assess the efficacy of CDP-choline (cytidinediphosphocholine) in the treatment of cognitive, emotional, and behavioural deficits associated with chronic cerebral disorders in the elderly. They concluded there was " Some evidence that CDP-choline has a positive effect on memory and behaviour in at least the short/medium term in elderly people with cognitive deficits associated with chronic cerebral disorders of the brain"
The full health benefits of eggs can only be realised if you store them properly - in the fridge - and cook them thoroughly to kill any potential bacteria. As a child, I loved my father's eggnogs, made with fresh, raw eggs blended with milk, vanilla and ice. These delicious treats are no longer considered a good option - unless pasteurised eggs are used in place of the raw eggs.