What is Cholesterol?
Cholesterol is found in your body and in the foods you eat (dietary cholesterol). Many times, cholesterol is referred to as “good” or “bad.” HDL cholesterol is known as the “good” cholesterol, while LDL cholesterol is known as the “bad” cholesterol. So why is HDL so good and LDL so bad? LDL cholesterol has been shown to contribute to plaque formation in the arteries which can lead to heart attacks and strokes. HDL cholesterol is considered the good cholesterol because it acts as a scavenger in the body. It travels through the arteries, picking up LDL cholesterol and carrying it back to the liver where it is removed from the body. However, many people don’t realize that there are different types of LDL cholesterol.
Types of LDL Cholesterol
Researchers discovered back in the 1960s that not all LDL cholesterol was the same. LDL particles can be large and buoyant or small and dense. The large, buoyant LDL doesn’t pass through the arterial wall as easily as the small, dense LDL. This is an important factor, since plaque formation takes place inside the arterial walls. That is why small, dense LDL is more harmful than large, buoyant LDL. Higher levels of small, dense LDL cholesterol have been seen in individuals with higher triglyceride levels. Medications that have been shown to reduce triglyceride levels have also been shown to decrease the proportion of small, dense LDL cholesterol particles. Triglyceride levels may be elevated for a number of reasons. Overweight, obesity, physical inactivity, smoking, excess alcohol consumption, and a diet high in carbohydrates (specifically sugar and refined grains) can raise triglycerides to dangerous levels in the body.
Lowering Blood Cholesterol
It’s important to know that the 2010 Dietary Guidelines for Americans, as well as the AHA, state that one egg per day does not result in elevated blood cholesterol levels or increased risk of cardiovascular disease. For those who are trying to lower blood cholesterol levels, the AHA does recommend limiting saturated fat to no more than five to six percent of total calories. That would be roughly 13 grams of saturated fat for someone consuming 2,000 calories a day. To put that into perspective, two tablespoons of butter contains about 15 grams of saturated fat. The 2010 Dietary Guidelines state that saturated fats should be reduced to less than 10 percent of your total calories and replaced with mono- and polyunsaturated fats (specifically omega-3 fatty acids). For those individuals needing to reduce their cardiovascular risk, the Guidelines recommend limiting saturated fat to seven percent of total calories. Trans fats are also major contributors in elevated blood cholesterol levels and should be eliminated from the diet.