When I had my blood test in December, the place I went to told me I needed to fast 14 hours prior to the test. Typically I've heard 12 hours. And that's what I wound up doing. Unless there's some studies I don't know about, I don't think fasting an extra hour or two would make that much difference in results.
It then makes me wonder, why fast at all. Wouldn't they get a more accurate reading after you've eaten something?
The reason for fasting before a lipid panel is that a measure of triglycerides is a part of that panel and is needed in calculating your TC. Fasting is necessary to get a clear picture of how much triglycerides remains in your bloodstream even when you have not eaten for 12-14 hrs. Some triglycerides circulate in the blood to provide fuel for muscles to work. Extra triglycerides are found in the blood after eating a meal—when fat is being sent from the gut to adipose tissue for storage. The test for triglycerides should be done when you are fasting and no extra triglycerides from a recent meal are present.
For 12 to 14 hours before the test, only water is permitted. In addition, alcohol should not be consumed for the 24 hours just before the test. Triglycerides change dramatically in response to meals, increasing as much as 5 to10 times higher than fasting levels just a few hours after eating. Even fasting levels can vary some day by day.
Usually triglyceride testing is not done alone; rather it is done in conjunction with a complete lipid panel. An exception might be if a patient is being treated for exceptionally high triglycerides to see if a treatment is working.
I was always told to fast for 12 hours. It usually will say on your order for blood work. I recently had a lipid panel done. The good and bad cholesterol were in ideal range, as well as total cholesterol. The thing that was out of whack was my triglycerides. More than double what would be ideal. I went home and did a search on tri levels and found this out. When going for a fasting lipid panel abstain from alcohol for at least 24 hours prior.Well I had a couple of drinks with dinner and then began my fast. Even though you fast for 12 hours alcohol stays in the bloodstream longer and it can and does (obviously) raise triglyceride levels. Anyhow I am glad I went with the diet and excercise route when given the choice of that or meds by the doc. I have 3 months to "shape up". I will try. I will definitely not have a drink or two for a day or two before my next blood test. See how it goes.