Fasting may not be necessary before cholesterol test

Before taking a cholesterol test, adults are typically told to fast for up to 12 hours or else levels in the bloodstream may be skewed by the recent meal. A new study, however, finds fasting may not be necessary after all.

The study, published Nov. 12 in the Archives of Internal Medicine, found the amount of time a person spent fasting prior to a cholesterol test had little impact on the end results.

"This finding suggests that fasting for routine lipid level determinations is largely unnecessary," wrote the authors.

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A cholesterol test, also called a lipid panel or lipid profile, measures the four types of lipids (fats) found in the blood, according to The Mayo Clinic. It measures low-density lipoprotein (LDL) cholesterol, sometimes called "bad cholesterol" because high levels of it could lead to plaque buildup in the arteries, potentially causing a heart attack and stroke.

The test also measures high-density lipoprotein (HDL) cholesterol, sometimes called "good cholesterol" because it helps carry LDL away from the blood. Cholesterol tests also measure total cholesterol and triglycerides, a type of fat found in the blood. People are typically told to have no food or liquids other than water for nine to 12 hours before the exam.

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Researchers at the University of Calgary in Alberta, Canada, examined laboratory data on cholesterol tests taken over a 6-month period in 2011 of over 209,000 participants (111,000 of which were women).

Participants had fasting times that ranged from less than one hour to 16 hours, and when the researchers crunched the data, they found minimal differences between patients' cholesterol screening results. On average, there was less than a 2 percent difference for total cholesterol and HDL cholesterol, less than a 10 percent difference for LDL cholesterol and less than a 20 percent difference for triglyceride levels -- regardless of fasting times.

Study author Dr. Christopher Naugler, assistant professor of clinical pathology at the University of Calgary, in Canada, told HealthDay that some patients, such as those with high triglyceride levels, may still require repeat fasting cholesterol tests. But for many others, the fasting test is largely unnecessary.

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"Eliminating fasting as a general requirement for cholesterol testing could greatly increase convenience for patients without significantly altering test results," he said.

In an accompanying editorial published in the same journal, Dr. J. Michael Gaziano, a chronic disease epidemiologist at Harvard Medical School in Boston, said the "exceedingly small" gain of information from a fasting blood test likely does not offset the logistical constraints put on patients, laboratories and doctors for the procedure.

"This, in my opinion, tips the balance toward relying on nonfasting lipid profiles as the preferred practice," he wrote.

[Nate650]

Choleserol numbers are largely meaningless and way too much emphasis is placed on them. Sadly this has resulted in the multi-billion dollar industry of cholesterol-lowering drugs. More important than the numbers is whether or not the cholesterol is oxidized. Some of the longest living and healthiest people have the highest cholesterol levels but they only ate real, wholesome, unprocessed food. Here's an eye-opening article on Mercola's site:

http://articles.mercola.com/sites/articles/archive/2010/08/10/making-sense-of-your-cholesterol-numbers.aspx

Note: I have no affiliation with the website and am only a reader of it.

[Medbob1]

As a Lab Tech, the issue is not only Cholesterol. Triglycerides are important blood lipids that help the physician to get a full picture for diagnosis of lipid disorders.
Triglycerides not only vary widely based upon the patient's fasting status, but can also interfere with other unrelated blood tests like cholesterol. The liquid portion of the blood (the part that is tested) can vary in color, based on triglyceride, from as clear as water, to as cloudy and opaque as milk. As many tests are performed by passing a beam of light through the sample mixed with other chemicals, it is obvious that Triglyceride can interfere.
The best testing that can be performed on a patient allows for both screening for disorder and also diagnosis of a disorder. By fasting, you insure that your Doctor gets the most accurate results possible on your "Lipid Panel", and allows him to not only screen for high cholesterol, but also diagnose any problems you have in metabolizing fats. The above study ONLY looks at screening cholesterol. Being that High Triglyceride only affects a percentage of folks, it makes sense that the data would suggest that you don't need to fast.
If you want to go to one of those Health Fairs and get cutesie numbers to take to your physician, go for it! It's fun and can confirm your suspicion that you are in good health. If your physician sends you to a lab to have blood drawn, don't forget to fast. It's an important part of helping us get the most accurate picture of your health to relay to your physician.