Go With Your Gut: CKD and Gut Health

Gut health has become a hot topic. Fermented foods such as kombucha, kimchi and kefir have become popular for their probiotic benefits and their role in gut health. But, why is gut health important? Well, we want our gut and digestive system to be healthy so that our body can absorb nutrients from the foods we eat to fuel us. Gut health has been found to play a major role in the risk for chronic diseases, such as inflammatory bowel disease, chronic kidney disease (CKD), cardiovascular disease, cancer, obesity and type 2 diabetes. What you eat can affect your gut microbiota. Read on to learn more about gut microbiota and how people with CKD can improve their gut health.

What is Gut Microbiota?

Gut microbiota is the collection of microorganisms (bacteria) found in the gut. There is bacteria that has a positive impact on the body and bacteria that has a negative impact. What you eat and your use of antibiotics affects the type of bacteria in your gut. You may have heard the words “prebiotics” and “probiotics.”

• Prebiotics are the dietary components that your gut bacteria need to grow. Think of prebiotics as fertilizer. Prebiotics are found in most fruits and vegetables that contain complex carbohydrates, such as fiber. Examples include asparagus, onions, apples and garlic. Oats and barley are also prebiotics. For more on prebiotics read “Prebiotics and Dialysis: What you Need to Know“.

• Probiotics are live bacteria that add to the healthy bacteria in your gut. Probiotic foods include yogurt, sauerkraut, kombucha and kimchi. These foods are made through fermentation with bacteria. For more on probiotics read “Probiotics for People on Dialysis“.

How Gut Microbiota Keeps Us Healthy

Beneficial gut bacteria produce short-chain fatty acids (SCFAs). SCFAs improve the digestive tract lining, improve glucose and lipid metabolism, and enhance absorption of certain minerals including calcium, magnesium and iron. Prebiotics can increase the production of SCFAs. Eating foods that naturally contain prebiotics may be beneficial. Probiotics limit the gut bacteria that is potentially harmful and help increase the amount of beneficial bacteria so that our gut continues to function at its best. 

Kidney Disease and Gut Microbiota

With kidney disease, kidney function declines and urea buildup damages the lining of the digestive tract. This can lead to thinning of the lining, also referred to as increased intestinal permeability, which can cause harmful bacteria from the digestive tract to enter the bloodstream. Research studies have found that people with chronic kidney disease (CKD) have reduced amounts of beneficial gut bacteria.

Reduced kidney function also leads to an increase in uremic solutes that would normally be cleared out by healthy kidneys. Some of these solutes result from the metabolism, or break down, of the gut bacteria. If these solutes are not cleared from the body, then they increase inflammation, cardiovascular risk, insulin resistance and the risk of death.

Ways to Improve Your Gut Microbiota

Studies have shown that combined prebiotic and probiotic supplements have improved the gut microbiota in other chronic diseases, but there is limited research in CKD. It is theorized that prebiotic and probiotic treatment would reduce uremic solutes, improve blood sugar control and lower triglyceride levels. However, there is not enough evidence to say that people with CKD should take prebiotic and probiotic supplements. More research is needed.   

Since prebiotic and probiotic supplements are not well studied in people with CKD, it is better to consume dietary sources. You may improve your gut microbiota by eating fruits and vegetables that contain prebiotics, such as apples and oatmeal, and by eating fermented foods that contain probiotics, such as yogurt and kimchi.

References:

1. A Renal Clinician’s Guide to the Gut Microbiota. Snelson et al. Journal of Renal Nutrition. September 2020; 30(5):384-395.
2. Prebiotics, Probiotics, and Your Health. Mayo Clinic. Accessed June 29, 2021. Published February 27, 2021. https://www.mayoclinic.org/prebiotics-probiotics-and-your-health/art-20390058.

Additional Kidney Diet Resources

Visit DaVita.com and explore these diet and nutrition resources:

• DaVita Food Analyzer
• DaVita Dining Out Guides
• Today’s Kidney Diet Cookbooks
• DaVita Kidney-Friendly Recipes
• Diet and Nutrition Articles                                                       
• Diet and Nutrition Videos
• Kidney Smart® Virtual Classes

This article is for informational purposes only and is not a substitute for medical advice or treatment. Consult your physician and dietitian regarding your specific diagnosis, treatment, diet and health questions.