Fasting and Oxalate Dumping: Autophagy and Microbes Unite

By Mary Ruddick

Hey There, Oxalates! Meet Your Match

Let’s talk about something a little… spicy. Oxalates. These naturally occurring compounds are hiding in your "detox" daily green smoothies. Overindulgence in oxalate-rich foods can cause quite the ruckus. They bind to minerals like calcium to form sharp, crystalline troublemakers that like to hang out in your tissues. But guess what? Your body has a secret weapon, and it's called autophagy, activated by—you guessed it—fasting. So, let’s dive into how this metabolic maneuver can help your body show oxalates the door. Oh, and we’ll throw in a little secret about your gut bacteria while we’re at it.

 Autophagy: The Body’s Recycling System

During fasting, autophagy—the body’s version of a spring clean—gets a little kick. It’s like your cells are on a mission to Marie Kondo your insides, breaking down damaged components and clearing out cellular debris. When autophagy is fully active, it boosts the performance of your liver and kidneys, which are the detox powerhouses of your body.

Enhanced Cellular Health and Function: As autophagy sweeps away damaged mitochondria and cellular clutter, your liver and kidneys get a boost. Healthier kidney cells, in particular, become even better at filtering out and excreting oxalates—those troublemakers that love to cause crystal chaos. By reducing oxidative stress and revving up cellular function, autophagy can indirectly help your body keep those oxalates in check.

 The Gut Microbiome: Your Unseen Allies in Oxalate Metabolism

Fasting doesn’t just get autophagy going; it also shakes things up in your gut microbiome—the bustling little metropolis of bacteria in your digestive tract. While Oxalobacter formigenes was once the reigning champ in oxalate breakdown, it’s gone MIA in a lot of modern guts (thanks, antibiotics). But don’t worry, there’s a backup team ready to jump in and save the day.

 Meet the Key Oxalate-Degrading Bacteria

Lactobacillus acidophilus LA-14: Despite not being quite as specialized as Oxalobacter formigenes, it still breaks down oxalates in the gut, helping to reduce absorption. Think of it as the bacteria that throws a wrench in the oxalate absorption plan, making the gut a less welcoming place for crystal formation.

  - Found: In the human gut, mouth, and vaginal canal; a little birth canal bonus for newborns.

  - Best Taken: With food, especially if there's a little fat in the mix.

  - Preferred Substrates: Think dairy—lactose, specifically.

  - Competition: Competes with other Lactobacillus strains and Bifidobacterium for prime real estate in the gut.

Lactobacillus plantarum WCFS1: A true multitasker, this subspecies can degrade oxalates and thrive in a variety of pH environments. It uses oxalates as a carbon source, making it particularly handy when fasting changes up the nutrient landscape in your gut.

  - Found: Hanging out in fermented favorites like sauerkraut, kimchi, and pickles, as well as breast milk.

  - Best Taken: With food, particularly if it's fermented or fiber-rich.

  - Preferred Substrates: Versatile with carbon sources.

  - Competition: Competes with other Lactobacillus strains and some Bifidobacterium.

Bifidobacterium lactis Bl-04: This one’s all about creating the right ambiance—fermenting complex carbs and producing short-chain fatty acids that lower your gut’s pH. A more acidic environment makes oxalates more soluble, making them easier to flush out.

- Found: In the guts of infants, passed along during breastfeeding, and cherished in many guts for its health benefits.

  - Best Taken: On an empty stomach for maximum gut colonization.

  - Preferred Substrates: Dietary fibers are its jam; it gets along well with protein metabolism byproducts.

  - Competition: Likes to keep its turf clear of other Bifidobacterium and some Lactobacillus species.

Enterococcus faecalis OG1RF: This hardy player can handle a tough environment and doesn’t back down from breaking down oxalates, especially when nutrients are scarce, like during a fast. It's not your everyday probiotic, but it's got the grit to stick around when the going gets tough.

  - Found: In soil, water, and, yes, your gut—picked up from food and the environment.

  - Best Taken: Not your go-to for everyday use; more of a clinical setting kind of deal.

  - Preferred Substrates: Flexible in its tastes—loves proteins.

  - Competition: Competes fiercely with other Enterococcus, and might push around some Lactobacillus and Bifidobacterium if it feels like it.

Fasting = Speed Dating with Your Gut Bacteria

Fasting quickly sorts out which microbes are staying and which are getting shown the door. When there’s no sugar in sight, only the strongest survive.

Microbial Composition Changes: Fasting starves out the less desirable bacteria that thrive on a high-sugar diet, leaving room for the more resilient, beneficial microbes to flourish. Enter our friends like Lactobacillus plantarum WCFS1 and Bifidobacterium lactis Bl-04, who can handle the challenge and love the low-nutrient environment.

Promotion of Beneficial Microbes: By keeping the gut environment on its toes, fasting can suppress the growth of unhelpful or even oxalate-producing microbes, allowing our friendly, oxalate-degrading bacteria to step up and take the stage. This microbial makeover can make your gut a happier, healthier place—one less likely to let oxalates stick around.

This, my magical microbes, can cause a rapid oxalate dump.

Ferment on my little microbial muses!

Citations:

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1. "Oxalate Metabolism in Health and Disease" - Journal of Clinical Investigation

   - This article provides a comprehensive overview of oxalate metabolism, its role in health, and how dysregulation can lead to conditions like kidney stones. It discusses the impact of diet, genetics, and microbial involvement in oxalate metabolism.

   - [Journal of Clinical Investigation](https://www.jci.org/)

2. "Fasting and Autophagy: The Role of Microbial Interactions" - Nature Reviews Microbiology

   - Explores how fasting-induced autophagy affects the gut microbiome, including changes in microbial composition, and highlights the shifts in bacteria that degrade oxalates.

   - [Nature Reviews Microbiology](https://www.nature.com/nrmicro/)

3. "Gut Microbiota and Oxalate Metabolism: Recent Advances" - Gut Microbes Journal

   - Discusses the various bacteria involved in oxalate metabolism, their pathways, and how changes in the microbiome due to antibiotics or diet can affect oxalate levels in the body.

   - [Gut Microbes Journal](https://www.tandfonline.com/toc/kgmi20/current)

4. "Role of Probiotics in Oxalate Metabolism: Mechanisms and Clinical Applications" - World Journal of Gastroenterology

   - This review examines how probiotics like Lactobacillus plantarum and Bifidobacterium lactis can impact oxalate metabolism and provides insights into potential clinical uses.

   - [World Journal of Gastroenterology](https://www.wjgnet.com/)

5. "Impact of Fasting on the Human Gut Microbiome" - Cell Reports

   - Investigates how intermittent fasting and prolonged fasting impact the composition and function of the gut microbiome, with a focus on beneficial microbial shifts.

   - [Cell Reports](https://www.cell.com/cell-reports)

6. "Oxalobacter formigenes and Its Role in Oxalate Homeostasis" - Journal of Bacteriology

   - A detailed exploration of the specific role of Oxalobacter formigenes in degrading oxalates, its decline in modern populations, and its relationship with other gut bacteria.

   - [Journal of Bacteriology](https://jb.asm.org/)

7. "The Effects of Dietary Intake on Gut Microbiota and Oxalate Metabolism" - Advances in Nutrition

   - Focuses on how different dietary components, including animal products, affect the gut microbiome and its ability to degrade oxalates, with emphasis on specific microbial subspecies.

   - [Advances in Nutrition](https://academic.oup.com/advances)

8. "Autophagy and Kidney Function: Implications for Oxalate Excretion" - American Journal of Physiology-Renal Physiology

   - Discusses the relationship between autophagy and kidney function, specifically how enhanced cellular function through autophagy may influence oxalate excretion.

   - [American Journal of Physiology-Renal Physiology](https://journals.physiology.org/journal/ajprenal)

9. "Microbial Modulation of Oxalate Metabolism: A New Approach to Prevention of Kidney Stones" - Urology Annals

   - Provides an in-depth look at the potential use of specific probiotics and microbial shifts to prevent kidney stones by modulating oxalate metabolism.

   - [Urology Annals](https://www.urologyannals.com/)

10. "Probiotics and Their Role in Oxalate Degradation: A Systematic Review" - Frontiers in Microbiology

    - A systematic review that compiles evidence on the effectiveness of various probiotics in degrading oxalates, detailing the mechanisms and clinical trials that support their use.

    - [Frontiers in Microbiology](https://www.frontiersin.org/journals/microbiology)

These sources provide a solid foundation for understanding the relationship between fasting, autophagy, oxalate metabolism, and the role of various microbial subspecies in this complex process.