So I've heard different views on "whole" eggs and wanted to get to the bottom of it. I found this article and it cleared a few things up for me.
The egg's image as a wholesome food has been tarnished in recent years, ever since a link was established between high blood cholesterol level and high incidence of cardiovascular disease . Egg is a rich source of dietary cholesterol and it is labeled as a "bad food" . Many have resorted to eating just the egg white to avoid the implications of heart disease, while others have rejected the intake of eggs altogether as a prescription to well being.
Contrary to popular belief that the egg is something to avoid, numerous research and long term studies have shown that eggs are a great dietary source of many fundamental (e.g. protein, choline, cholesterol) and non-fundamental (e.g. lutein, zeaxanthin) components that are essential for optimal health. In fact, many in the fore-front of anti-aging research believe that moderate egg consumption of one per day should be an integral part of a complete anti-aging diet.
Cholesterol
Eggs have been widely known for their high fat and high cholesterol content, providing about 200 mg of cholesterol per egg. Cholesterol from the egg comes exclusively from the egg yolk.
Ever since the discovery that links high blood cholesterol to an increased incidence of cardiovascular disease, the logical conclusion is that any food high in cholesterol should be avoided since consumption of such dietary cholesterol may lead to an increase in blood cholesterol. The hypothesis that "high dietary cholesterol leads to high blood cholesterol" has become such a standard dietary claim that anyone who wishes to avoid or lower the chances of getting heart diseases has to restrict their intake of eggs. Few people have carefully examined the evidences to this hypothesis.
The majority of studies conducted over the past two decades on eggs and cholesterol have shown that dietary cholesterol only has a weak link, at best, to blood cholesterol levels because there is only a relatively small change in blood cholesterol levels in response to changes in dietary cholesterol intake.
For example, Harvard researchers report in the April 21, 1999 Journal of the American Medical Association that they could find no relationship of moderate egg intake (I per day) with heart disease. Two large prospective studies of 38,000 men and 80,000 women looked at heart attacks and strokes in 8 to 14 years of follow-up after asking about dietary habits. There was no statistically significant difference in risk among people who ate eggs less than once a week compared with those who ate more than one egg a day. The only increase in heart disease risk was seen in diabetics, both men and women. Eighty percent of diabetics are obese. It is thought that the increased risk is linked more to obesity, although the exact mechanism is not known.
Researchers have further established that the average response to a 100 mg/day change in dietary cholesterol intake leads to a 2.5 mg/dl change in blood cholesterol levels. While some individuals are more sensitive to the effects of dietary cholesterol (15-20% of the population), the dose adjusted response factor in this group is still relatively small (3.2 vs. 1.6 for sensitive vs. resistant study subjects). For example, it can be estimated that reducing dietary cholesterol intake from 400 mg/day to 300 mg/day results in a plasma cholesterol reduction of 3.2 mg/dl in cholesterol sensitive individuals and as little as 1.6 mg/dl in cholesterol insensitive individuals.
In a study by Schnoh et al in 1994, the diet of 24 adults was changed by addition of two eggs per day (400 mg of cholesterol) for six weeks. The researchers found that their total cholesterol levels increased by 4%, while HDL cholesterol levels increased 10%. The dose adjusted response to the change in dietary cholesterol was 2.4 mg/dl per 100 mg/day. This study showed that moderate egg intake should not be rigorously restricted in healthy individuals.
In another study by Ginsberg et al in 1994, twenty-four young men were fed 30% fat diets with an addition of zero (128 mg cholesterol/day), one (283 mg/day), two (468 mg/day) or four (858 mg/day) eggs per day to the base diet. Each diet lasted eight weeks. The average blood cholesterol levels in the twenty-four subjects were 155, 161, 162, and 166 mg/dl for the zero, one, two and four eggs per day feeding periods. Plasma total cholesterol increased 1.5 mg/dl per 100 mg/day added dietary cholesterol.
Even more important in this particular study was the finding that there was no evidence that changes in dietary cholesterol intakes altered the postprandial plasma lipoprotein profile (lipoproteins thought to be involved in the development of atherosclerosis) and thus did not alter the atherogenic potential of the plasma lipoproteins. The data indicate that in the majority of healthy young men, an addition of two eggs per day to a low-fat diet has little effect on plasma cholesterol levels.
Ginsberg followed up with another study in 1995 with a controlled dietary cholesterol feeding study. This time in young women. The effects of feeding zero, one, or three eggs per day on plasma lipids and lipoproteins were measured. Results showed that the dose adjusted plasma cholesterol response was 2.8 mg/dl per 100 mg/day dietary cholesterol (a value higher than that obtained in males in the 1994 study). In women, however, the increase in total plasma cholesterol with dietary cholesterol occurred in both the atherogenic LDL cholesterol (2.1 mg/dl per 100 mg/day) and the anti-atherogenic HDL cholesterol (0.6 mg/dl per 100 mg/day). As found in the previous study in healthy young men, young women have the ability to compensate for an increased intake of cholesterol by adjusting the way cholesterol is handled by the body. The data shows that an addition of two eggs per day to the diet of healthy young women has little effect on plasma cholesterol levels in the majority of study subjects.
In addition to the lack of significant correlation between dietary and blood cholesterol, many studies have shown that dietary cholesterol increases both LDL and HDL cholesterol concurrently, with essentially no change in the important LDL: HDL cholesterol ratio. For example, studies have shown that a change of diet by increasing ingestion of 100 mg cholesterol raises LDL cholesterol by 1.9 mg/dL and HDL cholesterol by 0.4 mg/dL. The LDL: HDL ratio change went from 2.60 to 2.61. Risk for cardiovascular disease remained the same.
The average American diet derives over 40% of its calories from fat, and the type of fat consumed is usually saturated fat from animal sources such as beef and trans-fat commonly found in fast foods such as French fries. For people on such a "bad fat" diet, consumption of eggs should be reduced and monitored. For healthy individuals who derive only 30 percent of their calories from fat, a moderate intake of one egg a day should not be restricted. The use of dietary intervention as a way to reduce blood cholesterol level should therefore be undertaken with great care to take into consideration the high variability among individuals.
Cholesterol is a much-needed macronutrient in the body. Too low a level is not good, and too high is also not good. Recent studies have linked a low blood cholesterol level of under 150 mg/dl to increased rate of cancer. Optimum cholesterol level in our body should be around 200 mg/dl, with a properly balanced total cholesterol/ HDL cholesterol ratio of lower than 4 to 1.
Dietary cholesterol is, however, associated with a higher risk of gallstones whose primary component is cholesterol, hence the term; cholesterol gallstones. Excess cholesterol that is taken in through the diet will be absorbed into the blood stream. Some of the cholesterol is carried to the gall bladder, one place where it is eliminated.
Dietary cholesterol's link with the occurrence of coronary heart disease or fatality is clearly weak at best. Clearly, the egg is not the demon it has been made out to be at moderate consumption of one per day for the healthy individual.
Here's the link to the whole article.
http://www.drlam.com/A3R_brief_in_doc_format/2003-No3-Eggs.cfm
The egg's image as a wholesome food has been tarnished in recent years, ever since a link was established between high blood cholesterol level and high incidence of cardiovascular disease . Egg is a rich source of dietary cholesterol and it is labeled as a "bad food" . Many have resorted to eating just the egg white to avoid the implications of heart disease, while others have rejected the intake of eggs altogether as a prescription to well being.
Contrary to popular belief that the egg is something to avoid, numerous research and long term studies have shown that eggs are a great dietary source of many fundamental (e.g. protein, choline, cholesterol) and non-fundamental (e.g. lutein, zeaxanthin) components that are essential for optimal health. In fact, many in the fore-front of anti-aging research believe that moderate egg consumption of one per day should be an integral part of a complete anti-aging diet.
Cholesterol
Eggs have been widely known for their high fat and high cholesterol content, providing about 200 mg of cholesterol per egg. Cholesterol from the egg comes exclusively from the egg yolk.
Ever since the discovery that links high blood cholesterol to an increased incidence of cardiovascular disease, the logical conclusion is that any food high in cholesterol should be avoided since consumption of such dietary cholesterol may lead to an increase in blood cholesterol. The hypothesis that "high dietary cholesterol leads to high blood cholesterol" has become such a standard dietary claim that anyone who wishes to avoid or lower the chances of getting heart diseases has to restrict their intake of eggs. Few people have carefully examined the evidences to this hypothesis.
The majority of studies conducted over the past two decades on eggs and cholesterol have shown that dietary cholesterol only has a weak link, at best, to blood cholesterol levels because there is only a relatively small change in blood cholesterol levels in response to changes in dietary cholesterol intake.
For example, Harvard researchers report in the April 21, 1999 Journal of the American Medical Association that they could find no relationship of moderate egg intake (I per day) with heart disease. Two large prospective studies of 38,000 men and 80,000 women looked at heart attacks and strokes in 8 to 14 years of follow-up after asking about dietary habits. There was no statistically significant difference in risk among people who ate eggs less than once a week compared with those who ate more than one egg a day. The only increase in heart disease risk was seen in diabetics, both men and women. Eighty percent of diabetics are obese. It is thought that the increased risk is linked more to obesity, although the exact mechanism is not known.
Researchers have further established that the average response to a 100 mg/day change in dietary cholesterol intake leads to a 2.5 mg/dl change in blood cholesterol levels. While some individuals are more sensitive to the effects of dietary cholesterol (15-20% of the population), the dose adjusted response factor in this group is still relatively small (3.2 vs. 1.6 for sensitive vs. resistant study subjects). For example, it can be estimated that reducing dietary cholesterol intake from 400 mg/day to 300 mg/day results in a plasma cholesterol reduction of 3.2 mg/dl in cholesterol sensitive individuals and as little as 1.6 mg/dl in cholesterol insensitive individuals.
In a study by Schnoh et al in 1994, the diet of 24 adults was changed by addition of two eggs per day (400 mg of cholesterol) for six weeks. The researchers found that their total cholesterol levels increased by 4%, while HDL cholesterol levels increased 10%. The dose adjusted response to the change in dietary cholesterol was 2.4 mg/dl per 100 mg/day. This study showed that moderate egg intake should not be rigorously restricted in healthy individuals.
In another study by Ginsberg et al in 1994, twenty-four young men were fed 30% fat diets with an addition of zero (128 mg cholesterol/day), one (283 mg/day), two (468 mg/day) or four (858 mg/day) eggs per day to the base diet. Each diet lasted eight weeks. The average blood cholesterol levels in the twenty-four subjects were 155, 161, 162, and 166 mg/dl for the zero, one, two and four eggs per day feeding periods. Plasma total cholesterol increased 1.5 mg/dl per 100 mg/day added dietary cholesterol.
Even more important in this particular study was the finding that there was no evidence that changes in dietary cholesterol intakes altered the postprandial plasma lipoprotein profile (lipoproteins thought to be involved in the development of atherosclerosis) and thus did not alter the atherogenic potential of the plasma lipoproteins. The data indicate that in the majority of healthy young men, an addition of two eggs per day to a low-fat diet has little effect on plasma cholesterol levels.
Ginsberg followed up with another study in 1995 with a controlled dietary cholesterol feeding study. This time in young women. The effects of feeding zero, one, or three eggs per day on plasma lipids and lipoproteins were measured. Results showed that the dose adjusted plasma cholesterol response was 2.8 mg/dl per 100 mg/day dietary cholesterol (a value higher than that obtained in males in the 1994 study). In women, however, the increase in total plasma cholesterol with dietary cholesterol occurred in both the atherogenic LDL cholesterol (2.1 mg/dl per 100 mg/day) and the anti-atherogenic HDL cholesterol (0.6 mg/dl per 100 mg/day). As found in the previous study in healthy young men, young women have the ability to compensate for an increased intake of cholesterol by adjusting the way cholesterol is handled by the body. The data shows that an addition of two eggs per day to the diet of healthy young women has little effect on plasma cholesterol levels in the majority of study subjects.
In addition to the lack of significant correlation between dietary and blood cholesterol, many studies have shown that dietary cholesterol increases both LDL and HDL cholesterol concurrently, with essentially no change in the important LDL: HDL cholesterol ratio. For example, studies have shown that a change of diet by increasing ingestion of 100 mg cholesterol raises LDL cholesterol by 1.9 mg/dL and HDL cholesterol by 0.4 mg/dL. The LDL: HDL ratio change went from 2.60 to 2.61. Risk for cardiovascular disease remained the same.
The average American diet derives over 40% of its calories from fat, and the type of fat consumed is usually saturated fat from animal sources such as beef and trans-fat commonly found in fast foods such as French fries. For people on such a "bad fat" diet, consumption of eggs should be reduced and monitored. For healthy individuals who derive only 30 percent of their calories from fat, a moderate intake of one egg a day should not be restricted. The use of dietary intervention as a way to reduce blood cholesterol level should therefore be undertaken with great care to take into consideration the high variability among individuals.
Cholesterol is a much-needed macronutrient in the body. Too low a level is not good, and too high is also not good. Recent studies have linked a low blood cholesterol level of under 150 mg/dl to increased rate of cancer. Optimum cholesterol level in our body should be around 200 mg/dl, with a properly balanced total cholesterol/ HDL cholesterol ratio of lower than 4 to 1.
Dietary cholesterol is, however, associated with a higher risk of gallstones whose primary component is cholesterol, hence the term; cholesterol gallstones. Excess cholesterol that is taken in through the diet will be absorbed into the blood stream. Some of the cholesterol is carried to the gall bladder, one place where it is eliminated.
Dietary cholesterol's link with the occurrence of coronary heart disease or fatality is clearly weak at best. Clearly, the egg is not the demon it has been made out to be at moderate consumption of one per day for the healthy individual.
Here's the link to the whole article.
http://www.drlam.com/A3R_brief_in_doc_format/2003-No3-Eggs.cfm
