Dietary Ambiguities with Polycystic Kidney Disease (PKD)

The article we will be discussing today is:

What are the information needs and concerns of individuals with Polycystic Kidney Disease? Results of an online survey using Facebook and social listening analysis

Tiffany Ma and Kelly Lambert (2021).

BMC Nephrology Volume 22 Issue 263


Journal Club Discussion

“Are there foods that are less stressful on kidneys… or things I should avoid besides the broad low-sodium recommendation?” – study participant with PKD

As a PKD patient or family member of someone with PKD, have you ever returned home from a doctor’s appointment confused about something the doctor said, or curious about what to do or eat to help preserve your kidneys?  You then opened your computer to do a bit of searching. 

There have been very few studies to date that have looked into what information PKD patients are really looking for. The study by Tiffany Ma and Kelly Lambert documents what people with PKD are searching for online, what they perceive as major challenges of living with PKD, and overwhelmingly, the question of what do I eat?

Facebook groups can be a wonderful community-building tool to share information with other people who are living with PKD. Perhaps you even found this blog post through a PKD-oriented Facebook group. If that’s the case, you are not alone. Out of 536 participants who completed surveys for this study, 69.9% of them used Facebook to find information on PKD. The accessibility of online resources, and the feeling of camaraderie and support strongly resonated with the participants. But what are they looking for in these online spaces?

What do we want?

Information about the type of diet and nutrition guidelines for PKD!

When do we want it?

From the time of diagnosis!

A main conclusion from this study was: “The major information need expressed by participants with PKD was for dietary information.”

81% of participants searched online for PKD-specific dietary information. Ideally, participants wanted information from their primary care physician or nephrologist when they were initially diagnosed. They were hopeful they would be provided with online resources or pointed in the direction of credible information. The internet is a vast space that can provide a plethora of information. However, the internet also contains a large amount of contradictory or unvalidated information. 

Another main conclusion of this study was: “…many participants in this study expressed a tangible sense of frustration and confusion because of vague and inconsistent dietary information.”

…and patients reported… “… inability to access renal nutrition expertise as well as  inconsistent dietary information from primary care physicians and nephrologists.”

“Frustrations about the lack of specific information led many to conduct their own research online.”

These frustrations are illustrated in the words of PKD patients themselves, as cited in this study:

“…I just (want) simple meal plans… and recipes… according to what stage you’re in, how much protein, phosphorus and potassium…”

“(my biggest concern) is… am I doing the right thing (with my diet)? What should I do?”

“(I want information on) the effects of the Keto diet, intermittent fasting, & other dietary options potentially beneficial to those with PKD”

“Educating nephrologists worldwide. I find myself being more knowledgeable on modern clinical trials, medicines, diet, etc. for PKD patients”

So where do you go to find this information? 

“Creation of high-quality evidence-based resources for individuals with PKD is required” (Ma and Lambert, 2021). Expanding upon this conclusion, these high-quality resources also have to be easily accessible and more well-known among healthcare professionals treating people with PKD. 

Ma and Lambert wrote: “Programs such as the online Ren.Nu PKD Nutrition Program may help improve access to specialised credible dietetic care for people with PKD.”

We couldn’t agree more and thank the authors for the shout-out! 

The scientists at  Santa Barbara Nutrients are proud to have contributed to the development of the Ren.Nu program, which takes patients step-by-step through understanding the dietary requirements of PKD. Ren.Nu was developed around a plant-focused, clean and kidney-safe diet that avoids renal stressors while achieving the metabolic state of ketosis. The approach is the result of a collaboration between researchers and clinicians who’ve come together to provide individuals with dietary recommendations and interventions for PKD.  To learn more about this novel concept, you can watch an interview with Ren.Nu co-founder Jessiana Saville, where she shares her perspective on nutrition therapy for PKD.

The Ren.Nu program also runs a popular Facebook group that is moderated by dietitians and contains lots of free resources and tips along with great discussions and sharing of experiences by PKD patients. Anyone with PKD can request to join: https://www.facebook.com/groups/pkdnutrition 

Does the Ma and Lambert article sound like your journey of searching for PKD information? 

What do you commonly search for and what information do you wish you were given earlier on? 


Ma, T., and Lambert, K. (2021). What are the information needs and concerns of individuals with Polycystic Kidney Disease? Results of an online survey using Facebook and social listening analysis. BMC Nephrology, 22(1) 263. https://doi.org/10.1186/s12882-021-02472-1; PMID: 34261447

Renal Plasticity Revealed Through Reversal of PKD in Mice

The article we will be discussing today is:

Renal plasticity revealed through reversal of polycystic kidney disease in mice

Ke Dong, Chao Zhang, Xin Tian, Daniel Colman, Fahmeed Hyder, Ming Ma and Stefan Somlo (2021).

Nature Genetics Volume 53 Issue 12


Journal Club Discussion

Do you have polycystic kidney disease (PKD)?

Have you been told by your doctor that PKD is relentlessly progressive and only gets worse but never better?

Have you been told that there is nothing you can do to stop this disease, and that you should prepare yourself for the inevitable: dialysis or kidney transplantation?

Of course you have been told all this. That’s the current dogma.

Sidebar: What is PKD?

PKD is a common, genetically inherited disease caused by mutations in either the PKD1 or PKD2 gene. The disease leads to the growth of cysts in both kidneys that slowly cause tissue damage and scarring (fibrosis) in the kidneys until they eventually fail to function altogether. When this happens, an individual with PKD needs to go on dialysis. If a kidney donor can be found, the individual can also get a transplanted kidney. Besides the loss of kidney function, PKD causes numerous other symptoms and complications such as hypertension, pain, liver cysts, and brain aneurisms that can increase the risk of stroke.

Indeed, there is only one pharmacological treatment currently available that slows the progression of PKD, but it does not stop progression, let alone reverse it. So, the bar for PKD treatments is relatively low right now.

Everyone thinks that the deterioration of the kidneys in PKD is irreversible. And that’s, unfortunately, what is seen in clinical practice. Nobody ever gets better.

But is it POSSIBLE that PKD kidneys could get better with the right treatment? Has anyone ever tried this at least in the laboratory using animals with PKD?

It turns out that the answer is “yes”. Read on.

A recent paper in Nature Genetics (1) by Dr. Stefan Somlo’s group at Yale University used genetically engineered mice in which the PKD1 or PKD2 genes could be turned off first, and then turned on again. This genetic “flip-flop” had never been tried before.

What did they find? As one would expect, when the researchers turned off the PKD genes, the mice developed polycystic kidneys. Nothing new here. This has been done many times in many labs. But when the researchers turned the PKD genes back on – after the mice already had polycystic kidneys – the kidneys got better again. A lot better. The cysts shrank, fibrosis improved, and the kidneys functioned better. So, it is possible to reverse PKD, at least in mice and with some genetic trickery that “fixes” the “broken” PKD genes in all the kidney cells.

This is great news.

The researchers, however, also found that the disease reversal works best if the broken PKD genes are “fixed” relatively soon after kidneys became polycystic. If they waited too long, then the scarring in the kidneys became permanent.

Can the “genetic treatment” that was used in mice be applied to humans with PKD to reverse their disease?

Unfortunately, the answer is “no”. At least not for a very long time, perhaps never. Replacing the broken PKD genes with intact genes would be a form of gene therapy. Gene therapy is very promising for certain genetic diseases but not for PKD. There is really no method on the horizon that can achieve the gene replacement for every single kidney cell in a patient.

Have other treatments been shown to reverse PKD in rodents?

Here, the answer is “yes”. Reversal of PKD has already been shown by other groups previously. The group of Thomas Weimbs at the University of California in Santa Barbara already showed in 2010 that treatment of PKD mice with the drug rapamycin caused reversal of renal cysts and greatly improved kidney function (2). Unfortunately, rapamycin is a drug that has too many side effects to be useful in a chronic disease like PKD (3).

More recently, however, the same group at UCSB also showed that a ketogenic diet was able to reverse the disease in rats with PKD (4). Wait, a diet? Really? Yes, really. No drugs were needed in this dietary study (4, 5).

So, an exciting picture emerges: the new study (1) confirms that PKD is reversible with the right kind of treatment, at least in rodents.

How about humans? Could PKD be reversible in patients?

A clinical retrospective case series study was recently published – again by the Weimbs lab at UCSB (6). These researchers showed that PKD symptoms, including pain, hypertension and kidney function improved in a large fraction of the 131 individuals with PKD who had switched to ketogenic diets (6). While this study is preliminary and needs to be repeated, it is the first human study that showed that individuals with PKD can experience improvement of their disease.

Improvement? In humans with PKD? Yes, improvement in Homo Sapiens. This goes against long-standing dogma and against everything that patients have always been told.

With the new paper in Nature Genetics (1), now we have another mouse study that shows that improving PKD may not be such a crazy idea.

Importantly, this paper strongly suggests that interventions in PKD should start as early as possible before the scarring in the affected kidneys becomes so widespread that it cannot be reversed.

Bottom line: If you have PKD and your doctor tells you that there is nothing you can do about it, let them know about these studies.

The bar has been raised.


  1. Dong, K., Zhang, C., Tian, X., Coman, D., Hyder, F., Ma, M., and Somlo, S. (2021). Renal plasticity revealed through reversal of polycystic kidney disease in mice. Nature Genetics 1–15. https://doi.org/10.1038/s41588-021-00946-4; PMID: 34635846
  2. Shillingford, J.M., Piontek, K.B., Germino, G.G., and Weimbs, T. (2010). Rapamycin ameliorates PKD resulting from conditional inactivation of Pkd1. Journal of the American Society of Nephrology: JASN 21, 489–497. https://doi.org/10.1681/ASN.2009040421; PMID: 20075061
  3. Weimbs T, Shillingford JM, Torres J, Kruger SL, Bourgeois BC. Emerging targeted strategies for the treatment of autosomal dominant polycystic kidney disease. Clinical Kidney Journal. 2018 ;11(suppl_1):i27–i38. https://doi.org/10.1093/ckj/sfy089; PMID: 30581563
  4. Torres, J.A., Kruger, S.L., Broderick, C., Amarlkhagva, T., Agrawal, S., Dodam, J.R., Mrug, M., Lyons, L.A., and Weimbs, T. (2019). Ketosis Ameliorates Renal Cyst Growth in Polycystic Kidney Disease. Cell Metabolism 30, 1007-1023.e5. https://doi.org/10.1016/j.cmet.2019.09.012; PMID: 31631001
  5. Carney, E.F. (2020). Ketosis slows the progression of PKD. Nature Reviews Nephrology 16, 1–1. https://doi.org/10.1038/s41581-019-0226-4; PMID: 31654043
  6. Strubl, S., Oehm, S., Torres, J.A., Grundmann, F., Haratani, J., Decker, M., Vuong, S., Kaur Bhandal, A., Methot, N., Haynie-Cion, R., Meyer, F., Siedek, F., Korst, U., Müller, R-U., Weimbs, T.  (2021). Ketogenic Dietary Interventions in Autosomal-Dominant Polycystic Kidney Disease (ADPKD)– A Retrospective Case Series Study: First insights into Feasibility, Safety and Effects. Clinical Kidney Journal (in press). https://doi.org/10.1093/ckj/sfab162

Nutritional Management for Polycystic Kidney Disease (PKD)

Nutritional Management of Autosomal Dominant Polycystic Kidney Disease (ADPKD)

Whatis the latest Nutritional Management for ADPKD? 
Above is a webinar recording from the Virtual PKD Summit 2021, PKD Foundation of Canada, on September 3rd, 2021. Dr. Thomas Weimbs, PhD, Santa Barbara Nutrients President and UCSB Professor speaks on the nutritional management of ADPKD and a ketogenic-focused diet. There is a lot of information regarding diet and polycystic kidney disease. Watch above to see the most recent research! 

YouTube link: https://youtu.be/HxHUUDOy_sU  


 What are the distinct nutritional needs and limitations of individuals with ADPKD?

Recent research has shown that ADPKD is a metabolic disease and that the cells affected in ADPKD exhibit distinct metabolic abnormalities that drive disease progression. Individuals with ADPKD have metabolic abnormalities that can be addressed by nutritional management as detailed below. The specific nutritional interventions that are addressed with KetoCitra are provided by supplementing patients with two natural compounds, beta-hydroxybutyrate (BHB) and citric acid (citrate), in a formulation that also delivers beneficial minerals and an alkaline load.

For more specific nutrition needs, please visit: https://santabarbaranutrients.com/faq/#1632543363936-53c5b16f-2526

Breakthrough Patent Related to Polycystic Kidney Disease (PKD)

Santa Barbara Nutrients’ Scientists Awarded Breakthrough Patent Related to Polycystic Kidney Disease


University of California Professor, Dr. Thomas Weimbs, a recognized leader in the Polycystic Kidney Disease (PKD) research field and Dr. Jacob Torres, Head Researcher of Santa Barbara Nutrients (SBN), identified distinct metabolic polycystic kidney disease mechanisms that can be addressed by the unique formulation of two food ingredients that are Generally Recognized as Safe (GRAS): beta-hydroxybutyrate (BHB) and citrate. SBN’s first product, KetoCitra™, is a medical food for the dietary management of PKD and will be launched this year. KetoCitra™ is intended to be used under medical supervision and is covered by this new patent.

What is polycystic kidney disease (PKD)?

PKD is one of the most common, life-threatening genetic diseases, causing kidney enlargement and function loss over time. The disease affects over 600,000 Americans and 13 million people worldwide and is one of the leading causes of kidney failure requiring dialysis or kidney transplantation. There is no cure.

About KetoCitra™
The research by Dr. Weimbs and Dr. Torres showed that two natural compounds, beta-hydroxybutyrate (BHB) and citric acid (citrate), can help the nutritional management of PKD by addressing the metabolic abnormalities that manifest during the progression of the disease. KetoCitra is specifically designed with these two ingredients in a formulation that also delivers beneficial minerals and an alkaline load intended to support the balancing of urine pH.  The inclusion of calcium and magnesium helps to manage the dietary absorption of the renal stressors oxalate and inorganic phosphate.KetoCitra uses only ingredients that are generally recognized as safe (GRAS), is sodium- and sugar-free and formulated to be kidney-safe when used as directed. As a medical food, KetoCitra is to be taken under medical supervision. KetoCitra can be taken by itself but is recommended to be taken in conjunction with specific dietary and lifestyle changes. Researchers at SBN have collaborated with experienced renal dietitians to create a dietary program called Ren.Nu that is administered by the non-profit RenAlign. Patients in the Ren.Nu program, which launches in January 2022, learn to implement a plant-focused, kidney-safe ketogenic diet, together with KetoCitra, in a sustainable way.
“We are pleased that the U.S. Patent Office has recognized our unique research in understanding a complex disease like PKD. This is an important step in our company’s effort to bring affordable products to market that can bring hope to millions of people with PKD around the world,” said Dr. Weimbs, President and Founder of Santa Barbara Nutrients.
To read the full press release, follow this link: https://www.prweb.com/…/santa_barbara…/prweb18206928.htm

Dietary Interventions for Kidney Disease – Interview with a Renal Specialist

Santa Barbara Nutrients Interviews Renal Nutrition Specialist Jessianna Saville

Dr. Jacob Torres, Head Researcher at Santa Barbara Nutrients interviews Jessianna Saville who is a Registered Dietitian and Board Certified Specialist in Renal Nutrition (CSR). She is the President and Executive Director of KidneyRD and the non-profit organization, RenAlign, and co-creator of the Ren.Nu dietary program for PKD. Jessianna focuses on pioneering integrative nutrition approaches for CKD, runs courses for dietitians to teach them in-depth nutrition therapy for CKD, and develops nutrition resources for renal dietitians.

In this interview, Jessianna shares her deep knowledge about dietary interventions for kidney disease, the benefit of ketosis for those with PKD (polycystic kidney disease), and she explains what a plant-focused diet for PKD means.

To watch the full video, please visit: https://www.youtube.com/watch?v=LOwT5uf9kXI&t=865s