You’re probably used to getting blood drawn at your yearly check up with your doctor.  We use these tests to glean all kinds of information about our patients.  Depending on the age of the patient we may check for anemia (not enough red blood cells), lead level, Vitamin D, and cholesterol.  For routine blood tests, our patients can have them done anytime regardless of if they have recently eaten.  However, sometimes we ask that our patients have fasting labs done.  How do you do them and why are they done?

Fasting labs mean that you don’t eat or drink anything besides water for 8-12 hours before coming in for your blood draw.  You can have dinner the night before but nothing to eat in the morning before coming to the office.  You can, and should, take any medications you would normally take in the morning.

Be sure to drink water – lots and lots of water!  When you are dehydrated (don’t have enough water in your body) your veins are smaller which makes it harder to draw your blood.  You also may feel light-headed if you have not had enough water to drink.  Feel free to bring a snack with you to enjoy once your blood is drawn.

Fasting labs give us a more accurate look at your cholesterol, triglycerides and glucose (blood sugar).  When you eat or drink, nutrients and ingredients enter your blood stream and can falsely elevate these tests.  A fasting test gives your doctor more accurate information about your body.

If  you are not sure if you should fast before your labs, call our office to ask.