Page 1, 2
The kidneys' ability to recover from damage is limited. Scar tissue does not revert to functional tissue. Some patients have high expectations, believing the kidneys have an unlimited capacity for regeneration. Nephrologists are often skeptical of alternatives in kidney care, especially once there's been a critical loss of function. It's good for patients to understand that while we can't turn back the clock, we can optimize the function they do have and slow further damage.
A 2014 report from Stanford showed that kidneys are constantly remodeling in an adult and there is active cell division. This was a change from the previous idea that the kidneys were mostly static. This remodeling is likened to growth of a tree from the branches as each section of the kidney takes care of its own regrowth.12 However, if the damage to the kidney is extensive enough, it would be similar to a tree stump and regeneration to a fully functional kidney would not be feasible. This may change with stem cell research, but at present time we do our best to support kidney health and delay the need for dialysis.
There is a myriad of kidney supplements on the market, but unfortunately most do nothing to support kidney filtration. A problem in the supplement industry is that all kidney problems are grouped together whether it be urinary tract infections, kidney stones, or hypertension and very few address kidney filtration at all. Some of the natural supplements that support the kidneys are well-known, but not supplements commonly associated with renal health.
Actual human trials on natural supplements is lacking, but we can take evidence from animal models. One approach is the 5/6 nephrectomy model. The lab animal has 5/6 of their nephron mass removed (1 whole kidney and 2/3 of the other kidney), leaving them with 1/6 of the original kidney mass. This creates the conditions of hyperfiltration, similar to a kidney patient operating on a fraction of the original nephron mass. All of the lab animals undergo the 5/6 nephrectomy and half of them receive treatment and half of them don't. Many natural substances tested with the 5/6 nephrectomy model show promise of supporting chronically overworked kidney and improving filtration. Along with a kidney-friendly diet, lifestyle, and continued care with their nephrologists, supplements offer adjunct support to slow the progression of chronic kidney disease.
Medicinal mushrooms have a long history of use for kidney ailments in Asia, with the cordyceps mushroom in particular proving useful. Cordyceps has been researched for use with IgA nephropathy, diabetic nephropathy, lupus nephritis, and post-transplant care. With the 5/6 nephrectomy model, cordyceps improved filtration, reducing serum creatinine and BUN. There was also less proteinuria, fibrosis, and sclerosis of the kidney tissue.13
Icariin, a constituent of the herb Epimedium sagittatum, was shown to significantly reduce creatinine, BUN, and uric acid in the 5/6 nephrectomy model. It also increased stem cells capable of repair.14 Commonly known as horny goat weed (HGW), this herb is often found in male enhancement" formulas, and in those formulas may be mixed with herbs like yohimbe that could raise blood pressure. Traditional Chinese medicine attributes reproductive function to the kidneys, and indeed many kidney patients note low libido. Horny goat weed may help with low libido, and a study from China on men on dialysis noted significantly improved sexual function with HGW supplements.15
Resveratrol helped preserve renal function and attenuated sclerosis in the 5/6 nephrectomy model. The results were attributed to both increasing cellular energy with mitochondrial support16 and increasing nitric oxide.17 Cardiac support from resveratrol is an added benefit to the kidney patient. Supplements can be helpful, and the patient can incorporate dark grapes and berries into the diet, both of which are low potassium fruits.
Hibiscus is a natural ACE inhibitor. Prescription ACE inhibitors are used to reduce proteinuria and lower stress on the kidneys, as well as lower blood pressure; and hibiscus demonstrates these benefits as well. In the 5/6 nephrectomy model, hibiscus lowered creatinine and BUN. There was also less damage to the kidney tissue in the lab animal that received hibiscus.18
Rehmannia glutinosa has been used for renal support in TCM. It's also part of formulas like Rehmannia 8 used for energy and a variety of health concerns. When Rehmannia was tested in the 5/6 nephrectomy model, there was a reduction in serum creatinine and proteinuria. The renal tissue showed fewer injuries as well, and Rehmannia slowed the progression toward renal failure.19
Salvia miltiorrhiza is typically characterized as an herb for cardiac support, but it's also useful for kidney support. When studied in the 5/6 nephrectomy model, one active component of this herb, Tanshinone IIA, helped reduce serum creatinine and angiotensin II.20 Also known for its anxiolytic effect, Salvia miltiorrhiza may prove helpful for advanced kidney disease.
Another cardiac support supplement that may offer renal support is ubiquinol. In animal subjects with reduced renal mass under the conditions of salt loading, ubiquinol helped preserve renal function.21 Results were attributed to the antioxidant properties of ubiquinol, but supporting the electron transport chain may have also played a role. As many renal patients are elderly and/or on statins, ubiquinol supplementation is often a good choice.
The bioflavonoid rutin also improved creatinine in the 5/6 nephrectomy model. Similar to quercetin and found naturally in buckwheat, apple skins, figs, and rooibos tea, rutin may improve kidney filtration and help protect the kidneys from tubular damage and sclerosis.22 Rutin is often part of a bioflavonoid complex added to vitamin C but can be found by itself in capsules.
Adding to the long list of benefits of curcumin is supporting kidney filtration. The metabolite tetrahydrocurcumin, in particular, helps with renal fibrosis, hypertension, and proteinuria.23 Nephroprotection is attributed to both antioxidant status and mitochondrial support.24 Many kidney patients will also benefit from an improved lipid profile and blood sugar support.
As chronic insomnia is a huge struggle for many kidney patients, it is not surprising that melatonin makes this list of supplements that help filtration. It's hard to overestimate how disruptive chronic insomnia can be for kidney patients. Many kidney patients report years or decades of insomnia prior to overt kidney symptoms, while others only experience insomnia late in the progression of kidney issues. In lab rats with reduced renal mass, melatonin ameliorates oxidative stress, inflammation, proteinuria, and progression of renal damage.25 It also helps nocturnal blood pressure, as uncontrolled hypertension can make sleep difficult.26
In conclusion creatinine and eGFR are the markers for kidney health, but there are some circumstances where these indicators are not reliable. Other indicators of kidney function such as BUN can also vary. Once kidney issues are identified, there are a variety of supplements that may offer support. The 5/6 nephrectomy model is commonly used to simulate the conditions of progressed renal disease and may be a first step to further research in this area. In practice, patients often respond to a combination of supplements for renal support. Sometimes there is a pronounced improvement in creatinine, but even just holding them at their current level is enough for most to keep the need for dialysis at bay.
Page 1, 2
Dr. Jenna Henderson's practice, Holistic Kidney, is dedicated to the unique needs of renal patients. A kidney patient herself since 1993, she has experienced all stages of kidney disease firsthand. She is a graduate of the University of Bridgeport. Dr. Henderson has had several articles on kidney health published in Natural Medicine Journal, NDNR and the Townsend Letter. She has lectured extensively across the US to naturopathic doctors, kidney patients, and kidney professionals.
Dr. Henderson seeks to bridge the gap between mainstream nephrology and natural medicine. In her practice she helps patients sort through often conflicting information to understand what is appropriate for their individual needs and stage of kidney function. She is often able to help patients delay the need for dialysis. For those already in kidney failure, she helps patients find optimal wellness with dialysis or a transplant.