Fasting Lipids

What Is Meant By Fasting Lipids?

The term fasting lipids means that a when a lipid profile is taken by means of a blood test, a patent must have been fasting for the results to be accurate or meaningful. Lipids are oils which are present in our blood stream, and the lipids of primary interest are Low Density Level Cholesterol (LDL-C), High Density Level Cholesterol (HDL-C), and Triglycerides. The levels of these lipids in the blood plasma are measured to determine a person's risk of incurring heart disease, or suffering a heart attack or a stroke.

The LDL-C lipids are often referred to as “bad” cholesterol. If your bad cholesterol levels are too high, there is an increased chance of plaque forming on the interior walls of your arteries, hardening, and eventually restricting the flow of blood through an artery, and even blocking it, resulting in a stroke or heart attack.

The HDL-C lipids are called “good” cholesterol, and the higher the levels of HDL-C one has, the lesser is the chance of incurring heart disease. The level of the triglycerides in the blood plasma also needs to be kept below certain levels to lessen the risk of heart disease.

Bad Advice - The levels of these lipids are measured after a blood sample has been drawn following fasting, hence the name fasting lipids. The total time of fasting is typically 12 hours, during which time only water is allowed although some doctors or clinics will allow one to have a cup of black coffee in the interim. There may be instances where you will read a post on the internet indicating fasting is not required, and the idea of a fasting lipid really has no meaning. There is some truth to this, but in most cases such a statement is decidedly false, and by not fasting an incorrect measurement and analysis of your lipid levels will be the result. Since the whole purpose behind fasting lipids analysis is to verify the status of one’s health and assess an individual's risk of heart disease, ignoring fasting rules or recommendations would be counterproductive.

When Fasting Is Not Required - The key item in these tests is usually the LDL-C level. It needs to be kept low. The HDL-C level on the other hand needs to be kept high, while the triglycerides level needs to be low. The LDL-C level is not usually measured directly, but is determined by a formula based on the levels of other lipids. If one doesn't fast, these other lipids will not give an accurate picture of what the LDL-C level actually is. However, if a special blood test is taken and a specific laboratory test is performed solely to examine the LDL-C level in the blood, fasting is not required.

Why Fasting Is Normally Required - Knowing the levels of the other lipids besides the LDL-C level is very helpful to the physician which is why fasting lipids are generally required. While a doctor may prescribe medication or recommend lifestyle changes with the purpose of lowering LDL-C levels, he or she is usually also interested in keeping the triglycerides level low and in raising the HDL-C levels, and will want periodic tests to measure progress in these areas. Very few doctors are only interested in LDL-C, so very few would test for that lipid only. Lifestyle changes often represent the best means of keeping the bad cholesterol levels low, though medications called statins are often prescribed if the LDL-C levels are too high. Medication is also required at times to raise HDL-C levels, which at times can be difficult to accomplish. If one is an adult over 45 or 50, a physician may want to measure fasting lipids at the time of the annual physical checkup. For patients who have heart disease or have risk factors associated with heart disease, fasting lipids may be taken every 6 months, or even every 3 months.