Your doctor may schedule you for a blood test to measure your cholesterol levels if you have risk factors like a family history of heart disease, diabetes, smoking or high blood pressure. Cholesterol tests require dietary restrictions before your blood is drawn because eating or drinking shortly before the test can alter the results. Food and drink affects your cholesterol levels and gives an inaccurate reading.
Restrictions
Don't drink anything other than water before your cholesterol test, MayoClinic.com advises. Plain water keeps you from getting dehydrated and has no effect on your cholesterol reading. Typically the drinking restrictions apply for 9 to 12 hours before the test. Eating is totally restricted during that time period, so you cannot have any food prior to the blood work.
Timing
Avoid some of the inconvenience of being unable to eat or drink anything but water by scheduling your blood test appointment first thing in the morning. This timing allows you to spend most of your fast sleeping, so you do not have to worry about eating or drinking something inadvertently. Have some water when you wake up to help ward off hunger and thirst, then have your normal breakfast after your test.
Process
Your cholesterol check is a brief process, after which you can resume normal eating and drinking. A doctor, nurse or technician uses a needle and syringe to take blood from your arm. The puncture site is sterilized before the test, and the health care professional puts an elastic band on your upper arm to trap blood and make the process easier, according to Medline Plus. You can eat or drink whatever you wish after a successful blood draw.
Considerations
You may need to stop taking certain medications in addition to avoiding food and drinks other than water, Medline Plus advises. Ask your doctor about these potential restrictions, and do not withhold your medication unless instructed to do so. You may only use water to take your pills during the fasting period before your cholesterol check.
Warning
You may experience withdrawal symptoms if you typically consume a large amount of caffeine every day, then abruptly stop because of your pre-test fast. Typical caffeine withdrawal symptoms include a headache, fatigue and difficulty concentrating, Judy Fortin of CNN Health reports. Do not break your fast to alleviate these problems. Drink only water until the test is over, then have the caffeinated beverage of your choice. Withdrawal symptoms typically stop shortly after you get more caffeine into your body.
