Apr 18, 2012

Cracking the Myths on Eggs and Cholesterol

I wanted to share this information I have found because I know how easy it is to miss out on nutrition when you don't keep updated on your facts...  So here you go!  Say goodbye to egg whites!

During a lively debate on nutrition, a good friend the other day raised the link between eggs and cholesterol. This subject is one of curiosity because rather than being a culprit of disease, eggs are actually very good for us. First, we have to understand that cholesterol is not necessarily bad. Humans need it to maintain cell walls, insulate nerve fibres and produce vitamin D, among other things. Second, there are two types of important cholesterol: dietary cholesterol and blood cholesterol.

Dietary cholesterol is found in certain foods, such as meat, poultry, seafood, eggs, and dairy products. The second type (blood cholesterol, also called serum cholesterol) is produced in the liver and floats around in our bloodstream. Blood cholesterol is divided into two sub-categories:High-Density Lipoprotein (HDL), and Low-Density Lipoprotein (LDL).

LDL cholesterol is considered bad because it sticks to artery walls. Too much of it can cause heart problems, but scientists are now discovering that consuming food rich in dietary cholesterol does not increase blood cholesterol.

A 1999 study, published in the Journal of the American Medical Association (JAMA)suggest that those who consumed seven to 14 eggs a week had the same rate of cardiovascular disease as those whose consumption included no eggs.

In another study (February 2009 Nutrition Bulletin paper: “Eggs and Dietary Cholesterol – Dispelling the Myth”), Prof. Bruce Griffin and Dr. Juliet Gray reviewed studies of egg consumption, dietary cholesterol and heart disease risk. Their conclusion was that though dietary cholesterol can increase LDL cholesterol a small amount, the effect is clinically insignificant, and does not increase the risk of heart disease. In fact, eating eggs may increase HDL cholesterol, counteracting the effect of LDL cholesterol on heart disease risk.

These studies fly in the face of conventional wisdom on eggs, which advises people to eat no more than three or four eggs a week. In fact, health organizations including the British Heart Foundation, the American Heart Association, and the Food Standards Agency no longer advise that the number of eggs eaten needs to be limited. With the exception of people who have been advised to limit eggs for health reasons (such as those with familial hypercholesterolemia, a genetic predisposition to high cholesterol), eggs are now regarded by medical professionals to be a valuable contribution to a healthy, balanced diet, and can be eaten daily.

So what does raise blood cholesterol? One of the main theories centers on saturated fats. Of the three types of fat (saturated, monounsaturated and polyunsaturated), saturated fat raises blood cholesterol and LDL levels. It so happens that eggs contain mostly polyunsaturated fat, which can actually lower blood cholesterol if one replaces food containing saturated fat with eggs.

egg-battery-farmHowever, there are still some concerns with commercial egg production, due to scientifically formulated chicken feeds. Commercial production methods require hens to spend their entire life indoors, hopped up on antibiotics to prevent infections in  crowded quarters. Chicken feed is  altered to increase shelf life by removing spoilable nutrients from grains. Essential Fatty Acids (EFA’s) are also spoilable, so the linoleic and alpha-linoleic acids were replaced with a more stable and non-essential oleic acid. The result is an egg with the same amount of cholesterol, but less EFA’s to transport and metabolize it properly in the body. Plant sterols found in vegetables, which reduce the cholesterol content of eggs by up to 35 percent also were removed from the chickens’ diet. Commercial eggs therefore contain more cholesterol than home grown barnyard eggs.

Nutritional value of eggs
Chickens raised with lots of sunshine, fresh food, fresh air and  room to move produce eggs which are one of nature’s most nutritionally dense foods.
Eggs are packed with a number of nutrients. One egg has 13 essential vitamins and minerals for only 75 calories. Eggs are also a good source of high-quality protein including all nine essential amino acids, as well as healthy unsaturated fats. Lutein and zeaxanthin, two antioxidants that contribute to eye health, are also found in eggs.

**Choline – 23% Daily Value: Essential for normal functioning of all cells, including those involved with metabolism, brain and nerve function, memory, and the transportation of nutrients throughout the body. Choline also helps prevent birth defects, as well as helps promote brain and memory development in infants.

**Selenium – 23% Daily Value: Acts as an antioxidant to prevent breakdown of body tissues. Selenium works hand-in-hand with vitamin E to protect against some chronic diseases.

**Riboflavin – 14% Daily Value: Helps to produce energy in all the cells of the body.

**Vitamin B12 – 11% Daily Value: Works to support normal digestion and nerve cell function.

**Phosphorus – 10% Daily Value: Essential for healthy bones, teeth and cell membranes. Phosphorus is also required for energy production in the body.

**Pantothenic Acid – 7% Daily Value: Helps breakdown food and assists body cells in producing energy.

**Folate – 6% Daily Value: Promotes proper fetal development and red blood cell formation.

**Iron – 5% Daily Value: Plays an important role in red blood cell production and oxygen transport.

**Vitamin A – 5% Daily Value: Supports growth and maintains healthy skin, vision and immune function.

**Vitamin D – 5% Daily Value: Works with calcium to strengthen bones and teeth.

**Zinc – 4% Daily Value: Assists in maintaining immune function, as well as body tissue growth and repair.

**Vitamin B6 – 3.5% Daily Value: Keeps nerve transmission running smoothly and aids protein in immune function.

**Calcium – 3% Daily Value: Helps build and maintain strong bones and teeth. This mineral also plays an important role in nerve function, muscle contraction and blood clotting.

Percent Daily Values based on USDA National Nutrient Database for Standard Reference, Release 20 (2007), NDB No: 01123.
Anatomy of Eggs
egg-anatomyShell - Although the shell acts as a protective barrier for the inside of the egg, it is still very porous with approximately 17,000 pores through which air flows. The shell is largely composed of calcium carbonate (about 94%) with small amounts of magnesium carbonate, calcium phosphate and other organic matter including protein. Shell strength is greatly influenced by the minerals and vitamins in the hen’s diet, particularly calcium, phosphorus, manganese and Vitamin D.

If the diet is deficient in calcium, for instance, the hen will produce a thin or soft-shelled egg or possibly an egg with no shell at all. Occasionally an egg may be prematurely expelled from the uterus due to injury or excitement. In this case, the shell has not had time to be completely formed. Shell thickness is also related to egg size which, in turn, is related to the hen’s age. As the hen ages, egg size increases. The same amount of shell material which covers a smaller egg must be “stretched” to cover a larger one, hence the shell is thinner.

Shell Membranes - There are two membranes on the inside of the shell. One membrane sticks to the shell and one surrounds the white (albumen). The second line of defense against bacteria. They are composed of thin layers of protein.
Germinal Disk - The entrance of the latebra, the channel leading to the center of the yolk. A slight depression on the surface of the yolk, the entry for the fertilization of the egg. When the egg is fertilized, sperm enter by way of the germinal disc, travel into a tube-like thread called the “neck of latebra” to the center to the embryonic disc, a 2 to 3mm diameter structure in the nucleus of pander. Subsequently, a chick embryo starts to form.
White (Albumen) - There are two layers: thin and thick albumen. Mostly made of water, high quality protein and some minerals. Represents ⅔ of the egg’s weight (without the shell). When a fresh egg is broken, the thick albumen stands up firmly around the yolk.
Chalazae - Pronounced “kuh-LAY-zee”, it is a pair of spiral white strands attached to two sides of the yolk and anchor it to the shell. The fresher the egg, the more prominent the chalazee.
Yolk Membrane (Vitelline Membrane) - Surrounds and holds the yolk. The fresher the egg, the stronger the membrane.
Yolk - The egg’s major source of vitamins and minerals, including protein and essential fatty acids. Represents ⅓ of the egg’s weight (without the shell). Yolk colors range from light yello to deep orange, depending on the chicken’s diet.
Air Cell - Forms at the wide end of the egg as it cools after being laid. The fresher the egg, the smaller the air cell.

Source: www.panix.com
Eggs contain all the essential amino acids in the exact proportions required by the body for optimum growth and maintenance of lean, metabolically active tissue. So go ahead, egg up. We’ve been held back too long – enjoy them finally.