Eggs have gotten a bad rap over the last few decades. Deemed bad for the heart by health experts, they have been the subjects of criticism and scrutiny. But are our white (sometimes brown) friends really that unhealthy for us? In the last few years, numerous health organizations have been vindicating eggs' reputation. So what are we to believe; why were eggs chastised, only to be acclaimed again?
Old Egg Myths
It was previously thought that eggs raised blood cholesterol levels -- one of the main causes of heart disease. The yolk in a single large egg contains five grams of fat, so it was only natural for nutritionists to assume that eggs clogged up people's arteries, especially since they also contain dietary cholesterol .
Another myth was that cholesterol is fat. That is simply not true. Cholesterol is a waxy substance that resembles fat, but has little to do with it. Today, scientists know that cholesterol content in food and the cholesterol in our blood aren't as directly related as once thought. So to unravel the mystery that is the egg, one must look at cholesterol.
First, one has to understand that cholesterol is not necessarily bad. Humans need it to maintain cell walls, insulate nerve fibers and produced vitamin D, among other things. Second, there are two types of cholesterol: dietary cholesterol and blood cholesterol . Both are important.
Dietary cholesterol is found in certain foods, such as meat, poultry, seafood, eggs, and diary 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.
What is bad, however, is the amount of LDL blood cholesterol in the body. 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. At least that is what some experts believe (they are somewhat disagreeing on the matter... as usual).
Evidence showing that eating a lot of dietary cholesterol doesn't increase blood cholesterol was discovered during a statistical analysis conducted over 25 years by Dr. Wanda Howell and colleagues at the University of Arizona. The study revealed that people who consume two eggs each day with low-fat diets do not show signs of increased blood cholesterol levels.
So what does raise blood cholesterol? One of the main theories is that saturated fat does. 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.
If you're a bodybuilder, you need eggs...