8 Tips to Prepare for a Blood Draw: Exercise, Fasting & More

The numbers are staggering—2 billion blood tests conducted annually in the US. [1] Routine checkups, monitoring chronic conditions, assessing deficiencies—all common reasons people might do them.

You feel empowered when you finally get your results and find out what's going on under the hood. Making health and fitness decisions becomes simple. Although the benefits are clear, many people still have anxieties and fears beforehand, which is natural.

That's why we'll guide you on preparing for the lab visit to calm your pre-appointment nerves and ensure accurate biomarker levels. Let's explore simple steps you can take to ensure a smooth experience.

» Learn how you can use InsideTracker blood draw and analysis to create a personalized plan for achieving your health goals

7 essential steps to prepare for your blood draw

For a smooth blood draw, we've prepared some simple steps for you to follow; here's a recap:

1. Avoid strenuous exercise for two days
2. Fast for at least 12 hours
3. Schedule your blood draw for the morning
4. Avoid alcohol for at least 24 hours
5. Don't take supplements within 24 hours
6. Continue medication as recommended by your physician
7. Stay properly hydrated

» Learn more about the biomarkers InsideTracker measures

1. Avoid strenuous exercise for two days

Strenuous exercise can temporarily spike your liver enzymes, creatine kinase, and hsCRP. These biomarkers are involved in muscle breakdown and inflammation, so it's best you avoid exercise for at leas two days before your blood draw. [2,3,4]

If you're a beginner weightlifter, you should extend this period to about seven days maximum. Those uncomfortable with stopping their workout regimen completely can go outside for a light walk or do gentle stretches.

» Discover how weight training can help boost longevity

2. Fast for at least 12 hours

Your body maintains a delicately balances your biomarkers, all the time. Some nutrients and ingredients in food can throw that equilibrium off, affecting your test results.

» Thinking of fasting for health? What you need to know before you start

3. Schedule your blood draw for the morning

Most people schedule their test for the morning since it's easier to fast overnight. Some biomarkers like cortisol, glucose, and testosterone are best measured early in the day, too.

» Curious about what the numbers mean for your health? Here's how to read your blood test lab results

4. Avoid alcohol for at least 24 hours

Blood sugar (glucose), fat (triglyceride), and the liver enzyme GGT can go off the charts fast if you're drinking alcohol before your blood test. [6] We recommend to stop drinking it 24 hours before for the most accurate results.



» Discover what your blood tests can reveal about your liver health

5. Don't take supplements within 24 hours

Supplements usually have different nutrients that can temporarily boost your biomarker levels. To prepare and ensure your blood draw result is accurate, avoid them for 24 hours before your appointment.

Here are some bonus considerations:

• Vitamin/mineral IV infusions: If you've recently had these, discuss the impact on your blood draw results with your doctor. They can elevate blood levels of certain vitamins and minerals for an extended period.
• Biotin: We recommend you stop taking these supplements at least 72 hours before your blood draw. Biotin can interfere with the accuracy of some tests.

» Are you taking supplements? Here's everything you need know

6. Continue medication as recommended by your physician

While you should avoid supplements before your blood draw, following your doctor's specific instructions regarding over-the-counter or prescription medications is an exception.

» Discover how your menstrual cycle affects blood test results

7. Stay properly hydrated

Staying hydrated is crucial for maintaining overall health, and it's especially important when preparing for a test. It increased volume due to sufficient hydration makes veins easier for the phlebotomist to locate and helps them draw the blood quicker.

» Hydration is important for more than just blood testing. Find out how it impacts exercise

Ready, set, blood draw!

By following these steps, your blood draw will be a breeze. Make sure to set a reminder on your phone to ensure you don't miss your appointment, and grab a photo ID—that's all you need.

InsideTracker takes the hassle out of blood testing by handling everything else beforehand. You've already paid for the test, so there's no need to worry about payments on the day. Plus, they'll have all the necessary insurance details ready for the phlebotomist.

Now, relax and know your blood draw will be a smooth and efficient experience!

References:

1. M. L. Balter, J. M. Leipheimer, A. I. Chen, A. Shrirao, T. J. Maguire, and M. L. Yarmush, “Automated end-to-end blood testing at the point-of-care: Integration of robotic phlebotomy with downstream sample processing,” Deleted Journal, vol. 06, no. 02, pp. 59–66, Jun. 2018, doi: 10.1142/s2339547818500048. Available: https://pubmed.ncbi.nlm.nih.gov/30057935/
2. “Liver function tests - Mayo Clinic,” Sep. 12, 2023. Available: https://www.mayoclinic.org/tests-procedures/liver-function-tests/about/pac-20394595
3. H. K. Walker, W. D. Hall, and J. W. Hurst, “Clinical methods,” NCBI Bookshelf, 1990. Available: https://www.ncbi.nlm.nih.gov/books/NBK201/
4. P. R. Lawler et al., “Targeting cardiovascular inflammation: next steps in clinical translation,” European Heart Journal, vol. 42, no. 1, pp. 113–131, Mar. 2020, doi: 10.1093/eurheartj/ehaa099. Available: https://pubmed.ncbi.nlm.nih.gov/32176778/
5. G. L. Pennacchiotti, A. Campion, P. G. Milano, S. F. Benozzi, and G. Unger, “Coffee intake one hour prior to phlebotomy produces no clinically significant changes in routine biochemical test results,” Biochemia Medica, vol. 33, no. 2, pp. 165–172, Jun. 2023, doi: 10.11613/bm.2023.020705. Available: https://pubmed.ncbi.nlm.nih.gov/37324115/
6. “Gamma-glutamyl transferase (GGT) test.” Available: https://medlineplus.gov/lab-tests/gamma-glutamyl-transferase-ggt-test
7. N. Website, “NSAIDs,” nhs.uk, Feb. 24, 2023. Available: https://www.nhs.uk/conditions/nsaids/
8. “What are platelets in blood.” Available: https://www.redcrossblood.org/donate-blood/dlp/platelet-information.html