The kidneys perform several full-time jobs. In addition to removing wastes from your blood, they also regulate blood pressure, maintain healthy levels of potassium and phosphorus, and aid the maturation of red blood cells. As of 2011, there are no evidence-based, peer-reviewed studies that suggest bromelain helps with kidney function. If you are inclined to take bromelain, double check with your doctor before taking this supplement. Bromelain may not be right for you, particularly if you take warfarin, sedatives or antibiotics.
Bromelain
Bromelain supplements contain protease enzymes from the fruit and stem of the pineapple plant. Protease enzymes break large protein molecules into smaller pieces. For example, meat tenderizers, including papain from the papaya, are usually protease enzymes. Health food stores and vitamin shops usually stock bromelain, and dosage suggestions are provided by the manufacturer. Unlike other vitamins and minerals, bromelain is not an essential nutrient. It has not been approved for any particular purpose by the FDA.
Renal Function
Kidney function is also known as renal function. Doctors calculate renal function by measuring how much creatinine is your blood and plugging that value into a mathematical formula that includes a measure of the surface area of your body. While a small decline in renal function is usually not noticeable, a steady downward trend is cause for concern. When kidney function declines to 15 percent or less, some type of renal replacement therapy such as dialysis or transplant, is necessary to sustain life.
Alternative Uses
Alternative practitioners claim that bromelain is useful for shortening labor, preventing cancer and improving antibiotic absorption. The Natural Medicines Comprehensive Database reports that while there is insufficient evidence to support most of these claims, bromelain is "possibly effective" in relieving pain due to osteoarthritis if used with trypsin and rutin, and "possibly ineffective" for treating muscle soreness, knee pain and swelling. Curiously, there are no claims made about improving kidney function.
Recommendation
Patients with impaired renal function are very sensitive to prescription drugs and supplements. Even regular vitamin supplements with vitamin D and calcium can have unintended consequences. While the University of Maryland Medical Center says that bromelain is safe for healthy people, the safety of this supplement has not been evaluated in patients with impaired renal function. If you are a kidney patient, double check with your nephrologist before taking any supplement.
References
- MedlinePlus: Bromelain
- "Inflammatory Bowel Disease"; Dietary Supplementation with Fresh Pineapple Juice Decreases Inflammation and Colonic Neoplasia in IL-10-Deficient Mice with Colitis. L.P. Hale, et al.; December 2010
- National Kidney and Urologic Diseases Information Clearinghouse; The Kidneys and How They Work; September 2010
- University of Maryland Medical Center: Bromelain
