The Gut-Liver Axis: Why Dr. Jarod Checks Your Liver When Your Digestion Is Off

When a patient tells Dr. Jarod Ward they feel bloated after meals or their bathroom schedule is off, he thinks about the liver. That surprises people, since digestion feels like a stomach and intestines job. Researchers have a name for the connection, the gut-liver axis, and the plumbing behind it explains why he looks at both.

About 70 to 75 percent of your liver's blood comes from the gut

The liver has two blood supplies. The hepatic artery brings 25 to 30 percent. The portal vein brings "the remaining 70% to 75%," and the portal vein forms where the vein draining the intestines meets the vein from the spleen. So the liver sits directly downstream of your digestion.

A review in Nature Reviews Gastroenterology & Hepatology describes the gut and liver as communicating through "tight bidirectional links through the biliary tract, portal vein and systemic circulation." What you eat, and what your gut bacteria make from it, travels "to the liver through the portal vein and influence[s] liver functions."

The liver keeps watch on what comes out of your gut

Dr. Jarod calls this one of the liver's least-known jobs:

"The liver has little fingers or little detectors that feel inside the gut. And so if we get a gut infection, the liver is the one that actually alarms the rest of the immune system about what's going on in the gut, which is pretty cool. People don't know that."

The research language is drier, but it describes the same setup. Pieces of bacteria and fungi that cross from the gut are "recognized by immune receptors on liver cells such as Kupffer cells and hepatic stellate cells." Kupffer cells are cells inside the liver that carry those immune receptors, so the liver can react to what the gut lets through.

Bile is the liver's message back to the gut

The connection runs both ways. Here's how Dr. Jarod explains the return trip:

"The liver is very important for digestion. It makes bile and then sends the bile to be stored in the gallbladder, and then the bile is released to help process food and assimilate food."

Bile acids are "important physiological agents for intestinal nutrient absorption and biliary secretion of lipids, toxic metabolites, and xenobiotics." In plain terms, bile helps you absorb fats and nutrients, and it's one of the routes the body uses to send waste out.

Bile also helps manage the gut's population. Along with bile salts, the liver sends antimicrobial molecules into the intestine, which "maintains gut eubiosis by controlling unrestricted bacterial overgrowth." Eubiosis means a healthy balance of gut microbes. And the body reuses its bile: about 95 percent of bile acids are reabsorbed in the small intestine, with about 3 grams "recycled several times a day." More on that loop is in What Is Bile?

Sluggish bile is where Dr. Jarod connects the liver to bloating

If bile is the liver's contribution to digestion, then bile that doesn't move well shows up at the table. Dr. Jarod puts it this way:

"Sometimes the liver gets backed up and sludgy, and then the bile doesn't flow as well."

When that happens, he says, "that's going to impact digestive absorption."

That's why digestive concerns sit on his list of things he connects to the liver: "bloating, diarrhea, constipation." He describes the pattern he hears from patients in everyday terms: "They feel bloated after they eat. They don't have a bowel movement every day, or when they do, it's loose or way too difficult to pass." For him, those are reasons to look at the liver along with the gut.

Research sees strain on both ends of the axis at once

The gut-liver review notes that people who develop fatty liver often show changes in the gut too: steatosis "is characterized by increased intestinal permeability and dysbiosis." That means a gut lining that lets more through and a gut microbiome that's out of balance, showing up alongside fat in the liver. How common fatty liver has become is its own story, covered in Fatty Liver Is More Common Than You Think.

Alcohol is the clearest example of the axis at work. Most of the alcohol in food and drinks is absorbed by the stomach (about 20 percent) and the small intestine (about 70 percent), the same stretch of gut that drains to the liver through the portal vein. Dr. Jarod's take on drinking during a cleanse is in Can You Drink Alcohol on a Liver Cleanse?

Giving the liver room helps the whole loop

Dr. Jarod's cleanse is built on lowering what the liver has to handle, so it can get to the maintenance work, including the bile it sends back to the gut. In his words:

"We're trying to get the liver to not have to deal with all the angry guys in the room. We want the liver to be like, oh my gosh, I finally have time to fix the plumbing."

Why that means a strict three weeks is in Why Is a Liver Cleanse So Strict?

The full plan comes with the cleanse

Love Your Liver is Dr. Jarod's 21-day guided liver cleanse, and it's self-paced. The full meal plan, supplement schedule, shopping list and daily texts come with the cleanse. Your supplements ship to your door, and Day 1 starts the moment you tap start.

Prefer to start with a conversation? Dr. Jarod runs functional medicine and lab testing at Crown Chiropractic in Fort Myers. Call (239) 441-2275 to book a consultation.

Sources

• Dr. Jarod Ward, Crown Chiropractic. Liver episode on YouTube.
• Abdel-Misih SR, Bloomston M. Liver anatomy. Surgical Clinics of North America 2010;90(4):643-653.
• Tripathi A, Debelius J, Brenner DA, et al. The gut-liver axis and the intersection with the microbiome. Nature Reviews Gastroenterology & Hepatology 2018;15(7):397-411.
• Chiang JY. Bile acid metabolism and signaling. Comprehensive Physiology 2013;3(3):1191-1212.
• Gonzalez FJ. Nuclear receptor control of enterohepatic circulation. Comprehensive Physiology 2012;2(4):2811-2828.