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What’s wrong with eggs?
This is a question I am often asked – but why? Eggs are an excellent source of important nutrients, including high quality protein and essential fatty acids and contain plenty of vitamins and trace minerals.
But they also contain cholesterol. For many years now there has been a lot of concern over the rising incidence of heart disease and its heavy costs, so the medical establishment is trying to reduce the risk. A study into women’s health followed a group of women for an average of eight years and found a relationship between levels of LDL (Low Density Lipoprotein or ‘Bad Cholesterol’) and heart disease, other studies also concluded that lowering cholesterol reduced the risk of heart attack and strokes.
So, in the belief that diet is an important factor for blood cholesterol levels, in order to reduce the risk of heart disease, the American Heart Association (AHA) recommended that everyone eat less than 300 mg of cholesterol per day. And a large egg may contain up to 210 mg, so we should eat fewer of them.
But are these assumptions based on scientific evidence? This is now being questioned.
Cholesterol has been part of the human diet for millions of years. Sources include eggs, bone marrow and offal – just what our ancestors must have been eating. We don’t know how much cholesterol was consumed in the Stone Age, but it must have been more than the current recommendations.
Cholesterol plays a vital role in human metabolism, forming part of the cellular membranes, synthesising steroid hormones, vitamin D, bile – need I go on?
These facts challenge the view that dietary cholesterol presents a threat to human health. In fact it would be logical to think that we are well adapted to what we find in our native diet. An interesting debate has opened up about what are adequate amounts to recommend, and recent studies show that:
- There is no link between eating one egg a day and the risk of heart disease. There is actually a positive correlation between heart disease and egg consumption in diabetic patients, and a reduction in the risk of heart attacks.
- In approximately 75% of the population no correlation could be seen between egg consumption and blood cholesterol levels.
- In the 25% of the population that did respond to an increase of cholesterol in the diet, this could be seen as much in HDL as LDL cholesterol (the same in children as adults and the elderly). So there was no increased risk of blood clots.
- Small LDL particles are more dangerous than large ones, as they can penetrate the blood barrier and lead to hardening of the arteries. Egg consumption leads to an increase in the ratio of large sized particles of both LDL and HDL lipoproteins compared with small ones.
Cholesterol and EggsSo, if we accept this information, we can reach the conclusion that for a healthy person to eat up to one egg a day should, in principle, pose no risk to our health and we can benefit from many vitamins and minerals that are vital to a healthy metabolism.
But we can’t say which came first, the egg or the chicken!
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