Our gut is home to 100 trillion beneficial bacteria and what we eat has a tremendous impact on their composition. These bacteria constantly interact with the lining of the gut and their health is important for the maintenance of a healthy gut barrier as well as our overall health, especially in patients with kidney disease. In this blog, we will discuss feeding gut bacteria in kidney disease.

You can think of your gut’s bacterial ecosystem (or microbiota) as a society. Just like any society, there are good guys and bad guys, and we can measure such attributes as population and diversity. So, the three questions we ask when evaluating the microbiome are:

  1. Are there any bad bacteria that need to be evicted?
  2. What’s the bacterial population? Do you have enough inhabitants living in the gut?
  3. Is there enough bacterial diversity? Different bacteria have different jobs and contributions, so a broader diversity is an indicator for better health.

There are multiple factors that affect the answers to those questions, and here we’ll focus on diet. Eating the right foods is possibly the most effective way to cultivate a robust microbiome and defend against “bad-guy overgrowth”.
[bctt tweet=”Eating the right foods is possibly the most effective way to cultivate a robust microbiome and defend against “bad-guy overgrowth”” username=”inkidney”]

Feeding Gut Bacteria in Kidney Disease

Probiotics and Prebiotics: What’s the difference?

Prebiotics is a term used to describe “bacteria food” needed to cultivate a healthy microbiome. Bacteria primarily feed on fiber found in vegetables, fruit, and whole grains (not processed grains like bread and pasta). In fact, in people eating the Standard American Diet (SAD), which is high in animal protein and fat and low in dietary fiber, we see microbiome quantity and diversity significantly reduced. This imbalance is thought to be one of the major contributors to the chronic disease epidemic in the US.

Probiotics are live bacteria (and sometimes yeast) that are usually consumed through traditionally fermented foods, like kefir, kombucha, and sauerkraut and other fermented veggies, and are good for optimal gut function. They can also be taken as a supplement, which have grown in popularity as more research has suggested a benefit of supporting healthy gut bacteria.

As it turns out, focusing only on probiotics has yielded mixed results in the research. That’s because bacterial levels in the gut are transient unless supported with long-term dietary changes that incorporate regular intake of prebiotic fiber. Therefore, we need to look at both pre- and probiotic intake to optimize the microbiome.

[bctt tweet=” It turns out, focusing only on probiotics has yielded mixed results in the research. That’s because bacterial levels in the gut are transient unless supported with long-term dietary changes that incorporate regular intake of prebiotic fiber” username=”inkidney”]

 Fiber, Fiber, and More Fiber

There are two kinds of fiber: soluble and insoluble.

Soluble fiber is the kind of food that sucks up water and becomes like a gel. This helps to move digested food through the gut. Insoluble fiber does not break down during digestion. It passes through the gut intact, forming a sort of net, binding digested food byproducts together to create firm stool.

Fiber intake of at least 30 g/day is associated with reducing the risk of heart disease, obesity, diabetes, and even certain kinds of cancers like colorectal cancer.  These benefits are likely due to improved bowel movements, removal of toxins, and support of a healthy microbiome.

To preserve kidney function, animal protein sources should be reduced or restricted (more about that here). The research suggests, that plant-based protein sources might be ideal for kidney disease patients since they also double as sources of diverse dietary fiber.

Whole grains, legumes, nuts, and seeds make excellent sources of both fiber and protein. In addition, many vegetables and fruits have surprisingly significant amount of protein including avocado*, broccoli, cauliflower, mushrooms (especially Portobello and shitake), and seaweed.

Always keep in mind, though these foods may be generally healthy, in some patients with potassium restrictions, you need to consult with your renal nutritionist to personalize your diet.
Remember to always choose whole, fresh foods whenever possible and avoid processed foods that claim to have “added fiber”. They are usually packed full of fillers, sugars, grains, cereals and artificial ingredients.

[bctt tweet=”Remember to always choose whole, fresh foods whenever possible and avoid processed foods that claim to have “added fiber”. They are usually packed full of fillers, sugars, grains, cereals and artificial ingredients” username=”inkidney”]

The recommended daily fiber intake is somewhere between 30-40 grams of both soluble and insoluble fiber. The following options allow you to mix and match to achieve your daily fiber. Every kidney patient is different and needs an individualized approach; we’ve highlighted the foods within this list that are high in potassium with this symbol (*) and food high in phosphorus with this symbol (‡) so you can further customize to fit your needs:

  • 1 cup of cooked oatmeal = 4 g
  • 1/2 cup of raspberries = 4 g
  • 1 cup of avocado*= 10 g
  • 2 cups of romaine lettuce = 2.4 g
  • Medium-sized banana*= 3.1 g
  • 1 cup of carrots = 3.6 g
  • 1 cup of beets*= 3.8 g
  • 1 artichoke*= 10.3 g
  • 1 cup of Brussels sprouts = 6.4 g
  • 1 cup of kidney beans= 11.3 g
  • 1 cup of cooked split peas*= 16.3 g
  • 1 cup of cooked chickpeas = 12.5 g
  • 1 cup of cooked quinoa*= 5.2 g
  • 1 ounce of dried chia seeds= 10.6 g
  • 1 cup of blueberries = 3.5 g
  • 1 cup of strawberries = 3.3 g
  • 1 cup broccoli = 3 g
  • 2 carrots = 6.4 g
  • 1 cup of brown rice = 3.5 g
  • Half a cup of lentils‡*= 15.6 g
  • Medium-sized boiled sweet potato*= 3.8
  • 1 oz of almonds = 3.3 g
  • 1 apple = 5 g
  • 1 pear = 6 g
  • 1 ounce of dark chocolate= 3.1 g
  • 3 cups of popped popcorn = 3 g

[bctt tweet=”The recommended daily fiber intake is somewhere between 30-40 grams of both soluble and insoluble fiber” username=”inkidney”]

Cut out the sugar, You Are Sweet Enough Already

High-sugar diets can be a major disrupter of your gut microbiome, primarily because it feeds bad bacteria and yeast overgrowth. This is one of the proposed mechanisms contributing to metabolic diseases like diabetes and heart disease, two conditions associated with KD.

Should you take probiotics supplements?

Though supplementation may be very useful in some cases, the best long-term strategy is to increase the intake of per- and probiotics naturally through your diet. Traditionally fermented foods are a great source of naturally found probiotics, these include non-pasteurized traditionally-made kefir, sauerkraut, kimchi, miso, and pickled vegetables. However, for various reasons they may be restricted in some patients, so work with a nutritionist to implement the best strategy for gut bacteria balance – which may include a combination of food-based intervention and supplementation.

Other lifestyle factors that affect the microbiome

Interestingly, exercise may change the composition of the microbes in the gut for the better. Aim for at least 20 minutes of exercise daily and make it priority (you and your kidneys are worth it). In addition, stress can deplete the friendly flora and promote the growth bad bacteria. Although stress cannot always be avoided, find way to manage stress like breathing exercises and meditation, and do your best to avoid triggers.

It’s important to work with a physician and nutritionist familiar with an integrative approach to kidney disease. He/she can help you design a comprehensive plan that includes personalized dietary recommendations and supplements that promote healthy bacteria balance for optimal gut and kidney health.