How to Lower Your BUN Levels?

Introduction to BUN Levels

BUN stands for blood urea nitrogen. Urea is a waste compound that results from the metabolism (breakdown) of ingested proteins from your diet and protein released from your tissues; since urea forms in your liver and is later excreted through your kidneys, a BUN test can be useful to evaluate the function of your kidneys when used along with other tests. However, it is important to note that BUN levels can be affected by several factors; therefore, a BUN test should not be used as a stand-alone measurement to diagnose or assess kidney disease.

Nevertheless, having consistently high BUN levels can be a sign of an underlying condition; this is why you need to address this issue accordingly and work alongside your doctor to pinpoint the cause and develop a treatment strategy. In the meantime, you can try to lower your BUN levels by having a healthy lifestyle, getting proper hydration, eating a balanced low-protein diet, having enough rest, avoiding stressful situations, and using coping techniques to deal with your stress.

What is BUN?

Blood urea nitrogen, also known as BUN, is a test that can be useful to determine the health of your kidneys when used in conjunction with other tests, such as creatinine. A BUN test measures the nitrogen component of urea, which is a waste by-product of protein breakdown that forms in the liver and travels through your bloodstream to your kidneys, where it gets released through your urine. (1, 2)

What is a Normal BUN Range?

Generally, the normal level of BUN ranges from 6 to 20 mg/dl; however, these values may vary slightly depending on the laboratory and the method used for testing. (3, 4)

What Can Cause BUN Levels to Rise?

High BUN levels can happen for several reasons, such as: (3, 5-10)

  • Increased protein intake from your diet
  • Dehydration
  • Stress
  • Strenuous exercise
  • Chronic kidney disease (CKD)
  • Acute kidney injury (AKI)
  • Fever
  • Infections
  • Tumors of the urinary tract
  • Heart problems (such as severe congestive heart failure or a recent heart attack)
  • Bleeding from the gastrointestinal tract
  • Pregnancy
  • Severe burns
  • Use of certain drugs like corticosteroids and some antibiotics

What are the Symptoms of High BUN levels?

Since high BUN levels can happen for many reasons, you may experience several symptoms or none at all, depending on the specific cause and the timeframe since you first started experiencing high BUN levels. However, if you do experience symptoms, these may include: (8, 11, 12)

  • Frequent need to urinate
  • Constantly waking up at night to urinate
  • Foamy urine
  • Bloody urine
  • Difficulties or burning sensation when urinating
  • Fatigue
  • Loss of appetite
  • Muscle cramps
  • Numbness and/or swelling, especially in your limbs
  • Constant pain in your flank areas
  • Unintended rapid weight changes, either loss or gain

What Health Problems are associated with High BUN Levels?

In a population study, higher BUN levels correlated with increased diagnosis of Diabetes Mellitus. However, this may be subject to other influencing factors, which need further research to clarify. (13)

In critically ill people who have been admitted to ICU (intensive care unit) and in people who need to undergo heart surgery, high BUN levels have been associated with an increased mortality rate and stroke risk. (14-16)

What Can I Do to Lower My BUN Levels?

The first thing to do is to pinpoint the cause of your high BUN levels. As previously discussed, there are a lot of things that can cause your BUN levels to increase, so in order to keep them within a normal range, you need to work with your doctor to find and address the cause of the issue. Knowing this, let us take a deeper look into the specific things you can do to keep your BUN at a normal range:

1. Rule out Medical Problems

Since high BUN levels can indicate either acute (sudden) or chronic (long-term) kidney issues, your healthcare provider will indicate other lab tests to assess your renal function. If you have kidney problems, then you need to work with your doctor to address this issue. The main goal of managing increased BUN levels is to prevent further damage to your kidneys and to improve your overall renal function.

However, if you do not have kidney problems but your BUN levels remain high, your doctor may indicate other lab tests and/or imaging studies to diagnose or rule out any other medical condition that may be causing your BUN levels to rise.

2. Keep an Eye on your Medications and Supplements

Certain drugs can cause BUN levels to rise. Make sure to tell your doctor about any drugs you are taking and whether you have recently changed your dosage or intake frequency. Your doctor may adjust the dosage or change your medication to help lower your BUN levels.

Some of the most frequent drugs that may cause abnormal BUN levels include: (17)

  • Chloramphenicol
  • Streptomycin
  • Cephalexin
  • Rifampin
  • Amphotericin B
  • Penicillin
  • Gentamicin
  • Vancomycin
  • Diuretics, such as furosemide, spironolactone, and hydrochlorothiazide
  • Non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, aspirin, and naproxen
  • Lithium
  • Carbamazepine
  • Celecoxib
  • Methotrexate

On the other side, herbal supplements and even natural diuretics (such as caffeine) can also cause damage to the kidneys, especially in people with kidney disease. Furthermore, since herbal supplements are not regulated by the U.S. Food and Drug Administration (FDA), it is difficult to ascertain the effective dosage and effectiveness of these supplements; besides, herbal supplements can even contain certain compounds, like heavy metals, that can cause direct damage to the kidneys. (19)

3. Make Sure to Get Enough Hydration

Inadequate water intake is one of the common reasons for an isolated BUN increase in an otherwise healthy person, in the context of a normal creatinine.

Several studies recommend approximately three liters of water per day in males, and two to two and a half liters in females. However, this is highly variable among people, depending on factors such as daily activities. Moreover, healthy people are able to regulate their water intake by their thirst mechanism. (20-21)

4. Reduce Your Dietary Protein Intake

Excessive dietary protein intake is another frequent reason for BUN levels to increase; therefore, a low-protein diet can help lower your BUN levels. (22)

Foods that are high in protein, meaning that you should avoid or limit their intake, include:

  • Meats (poultry, beef, fish, pork)
  • Dairy products (milk, cheese, yogurt -especially Greek yogurt-)

In some cases, the intake of protein supplements, such as whey protein powder or similar products, can increase your BUN levels. In this case, all you need to do is to adjust your protein dosage according to your daily needs. Your daily goal should be to consume a maximum of 0.028 oz (0.8 grams) of protein per 2.2 lb (1 kilogram) of your body weight. (23)

It is important to bear in mind that this recommendation may vary according to the daily physical activity. You should talk to your doctor or dietician to find the appropriate amount for you.

You can also try to increase your daily intake of high-fiber, low-protein foods, which include fruits, vegetables, grains, non-sugary cereals, and healthy fats like nuts and avocados, as part of a healthy diet.

5. Reduce Your Stress Levels

Stress induces the release of a hormone called cortisol in the body, which in turn can contribute to an increase in BUN levels.

You can try different alternatives and approaches to keep your stress under control. Good options include breathing exercises, meditation, exercise, and mindfulness. If you are under constant stress in your daily life, and you feel you can’t get it under control, you should consider talking to a licensed therapist or counselor who can provide you with the right tools to help you manage your stress levels. (24)

6. Get the Right Amount of Exercise

Exercise is a great way to lower your stress levels, which in turn helps keep your BUN levels at a normal range. The American Heart Association recommends 150 minutes of weekly aerobic exercise, which can be split into sessions of 30 minutes five days a week. (25)

However, excessive exercise can be counterproductive to lower your BUN levels as it can put your body in a constant state of physical stress, leading to muscle soreness, mood changes, and sleep difficulties, especially when you are overtraining and not eating enough, and/or not allowing enough time for your body to recover in between training sessions.

See Also

BUN Lab Values

What are the Creatinine Lab Values

What are the Normal Lab Values

Grants for Laboratory Equipment

Best Medical Device Companies

  1. Hosten AO. BUN and Creatinine. Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition. Boston: Butterworths; 1990. Chapter 193.
  2. Lyman JL. Blood Urea Nitrogen and Creatinine. Emergency Medicine Clinics of North America. Volume 4, Issue 2, 1986. Pages 223-233.
  3. 001040: Urea Nitrogen. Labcorp [Internet]. [cited 2023May17]. Available from: https://www.labcorp.com/tests/001040/urea-nitrogen
  4. 214-996-9535-0 SAMPLE REPORT. Labcorp [Internet]. [cited 2023May17]. Available from: https://files.labcorp.com/testmenu-d8/sample_reports/001040.pdf
  5. Baum N, Dichoso CC, Carlton CE. Blood urea nitrogen and serum creatinine: Physiology and interpretations. Urology. Volume 5, Issue 5, 1975. Pages 583-588. Available from: https://www.sciencedirect.com/science/article/abs/pii/0090429575901053
  6. Wasung ME, Chawla LS, Madero M. Biomarkers of renal function, which and when?. Clinica Chimica Acta. Volume 438. 2015. Pages 350-357. Available from: https://www.sciencedirect.com/science/article/abs/pii/S000989811400391X
  7. Blood urea nitrogen (BUN) test – Mayo Clinic [Internet]. [cited 2023May19]. Available from: https://www.mayoclinic.org/tests-procedures/blood-urea-nitrogen/about/pac-20384821
  8. BUN (Blood Urea Nitrogen). National Library of Medicine [Internet]. [cited 2023May19]. Available from: https://medlineplus.gov/lab-tests/bun-blood-urea-nitrogen/
  9. Tomizawa M, Shinozaki F, Hasegawa R, Shirai Y, Motoyoshi Y, Sugiyama T, et al. Patient characteristics with high or low blood urea nitrogen in upper gastrointestinal bleeding. World J Gastroenterol. 2015 Jun 28;21(24):7500-5. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4481445/
  10. Gowda S, Desai PB, Kulkarni SS, Hull VV, Math AA, Vernekar SN. Markers of renal function tests. N Am J Med Sci. 2010 Apr;2(4):170-3. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3354405/
  11. Blood Urea Nitrogen – Health Encyclopedia – University of Rochester. [Internet]. [cited 2023May20]. Available from: https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=167&contentid=urea_nitrogen_serum
  12. Chronic kidney disease (CKD) – National Kidney Foundation [Internet]. [cited 2023May20]. Available from: https://www.kidney.org/atoz/content/about-chronic-kidney-disease
  13. Xie Y, Bowe B, Li T, Xian H, Yan Y, Al-Aly Z. Higher blood urea nitrogen is associated with increased risk of incident diabetes mellitus. Kidney Int. 2018 Mar;93(3):741-752. Available from: https://pubmed.ncbi.nlm.nih.gov/29241622/
  14. Beier K, Eppanapally S, Bazick HS, Chang D, Mahadevappa K, Gibbons FK, Christopher KB. Elevation of blood urea nitrogen is predictive of long-term mortality in critically ill patients independent of “normal” creatinine. Crit Care Med. 2011 Feb;39(2):305-13. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3448784/
  15. Arihan O, Wernly B, Lichtenauer M, Franz M, Kabisch B, Muessig J, et al. Blood Urea Nitrogen (BUN) is independently associated with mortality in critically ill patients admitted to ICU. PLOS ONE. 2018;13(1). Available from: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0191697
  16. Miura M, Sakata Y, Nochioka K, Takahashi J, Takada T, Miyata S, et al. Prognostic impact of blood urea nitrogen changes during hospitalization in patients with acute heart failure syndrome. Circ J. 2013;77(5):1221-8. Availble from: https://pubmed.ncbi.nlm.nih.gov/23392088/
  17. Arnan MK, Hsieh TC, Yeboah J, Bertoni AG, Burke GL, Bahrainwala Z, et al. Postoperative blood urea nitrogen is associated with stroke in cardiac surgical patients. Ann Thorac Surg. 2015 Apr;99(4):1314-20. Available from: https://pubmed.ncbi.nlm.nih.gov/25683323/
  18. Saker BM. Everyday drug therapies affecting the kidneys. Aust Prescr 2000;23:17-9. Available from: https://australianprescriber.tg.org.au/articles/everyday-drug-therapies-affecting-the-kidneys.html
  19. Herbal Supplements and Kidney Disease. National Kidney . [Internet]. [cited 2023May20]. Available from: https://www.kidney.org/atoz/content/herbalsupp
  20. Sawka MN, Cheuvront SN, Carter R. Human water needs. Nutr Rev. 2005 Jun;63(6 Pt 2):S30-39. Human water needs – PubMed (nih.gov)
  21. Meinders AJ, Meinders AE. [How much water do we really need to drink?]. Ned Tijdschr Geneeskd. 2010;154:A1757. [How much water do we really need to drink?] – PubMed (nih.gov)
  22. U.S. Department of Health and Human Services and U.S. Department of Agriculture. 2015 – 2020 Dietary Guidelines for Americans. 8th Edition. December 2015. Available at https://health.gov/our-work/nutrition-physical-activity/dietary-guidelines/previous-dietary-guidelines/2015.
  23. Wu G. Dietary protein intake and human health. Food Funct. 2016 Mar;7(3):1251–65. Dietary protein intake and human health – PubMed (nih.gov)
  24. Hofmann SG, Asnaani A, Vonk IJ, Sawyer AT, Fang A. The Efficacy of Cognitive Behavioral Therapy: A Review of Meta-analyses. Cognit Ther Res. 2012 Oct 1;36(5):427-440. Available from: https://pubmed.ncbi.nlm.nih.gov/23459093/
  25. Haskell WL, Lee IM, Pate RR, Powell KE, Blair SN, Franklin BA, et al. Physical activity and public health: updated recommendation for adults from the American College of Sports Medicine and the American Heart Association. Med Sci Sports Exerc. 2007 Aug;39(8):1423–34.Physical activity and public health: updated recommendation for adults from the American College of Sports Medicine and the American Heart Association – PubMed (nih.gov)

Follow us