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What Is the Connection between the Digestive System and Urinary System?

Jennifer Long
Jennifer Long

The digestive system and urinary system are closely connected, as one leads to the other. Digestion begins through the intake of food, which travels through the stomach, small intestine, and large intestine. This process is how the body absorbs nutrition from food. Everything that is broken down is sent to the kidneys through the blood. After the kidneys have filtered out the liquid waste, it goes to the bladder to be disposed of through the urine.

Many medical professionals and organizations refer to the digestive system and urinary system together because of how these systems work with each other. The digestive system breaks down food for the nutrients the body needs, and then the excretory system, which includes the urinary system, gets rid of waste. Each system has its own set of organs, but they are connected through the processes they perform.

The digestive system sends waste to the urinary system.
The digestive system sends waste to the urinary system.

Food enters through the mouth and travels down the esophagus to the stomach. Acids in the stomach break down the food, and it travels to the small intestine, where enzymes break it down further and nutrients are absorbed. The remaining solid waste goes to the large intestine. Liquids are absorbed through the walls of the small and large intestines and carried through the circulatory system and into part of the urinary system.

The digestive tract begins at the mouth and ends with the anus and includes all the organs in between.
The digestive tract begins at the mouth and ends with the anus and includes all the organs in between.

Blood travels to the kidneys to be filtered. The kidneys reabsorb nutrients and filtering out toxins and other harmful products from the blood. The removed waste is compiled and sent to the bladder. As the waste is added, the bladder fills with urine. Once it is full, the bladder empties all of the wastes.

On its own, the digestive system’s main purpose is to digest food and provide nutrients for the body. The urinary system is responsible for removing liquid waste that the body does not need. Both systems rely on each other to ensure a person remains healthy.

A urologist is a medical doctor who specializes in diseases and conditions of the urinary system.
A urologist is a medical doctor who specializes in diseases and conditions of the urinary system.

Due to how the digestive system and urinary system are connected, problems can occur in one system that can also affect the other. If, for example, the digestive system cannot properly break down food, excess toxins can be passed to the urinary system. This can sometimes result in too many toxins remaining in the bloodstream. If the kidneys are not functioning at full capacity, the toxins that come from the digestive system cannot be filtered and remain in the body or are recirculated into the blood.

What Is the Connection Between the Digestive System and the Urinary System?

As previously discussed, the digestive and urinary systems are physically interconnected. They work hand in hand to break down food into nutrients the body uses to maintain and improve functions.

What Diseases Result From Connection Between the Digestive and Urinary Systems?

Because the digestive and urinary systems interrelate, diseases that attack one system can quickly begin to affect the other as well. Some illnesses affect both the digestive and urinary systems.

Chronic Kidney Disease

Also known as chronic kidney failure, this condition is the result of several other conditions, including: 

  • Diabetes
  • Obstruction of the urinary tract
  • High blood pressure
  • Glomerulonephritis
  • Recurrent kidney infection
  • Genetic diseases such as polycystic kidney disease
  • Interstitial nephritis
  • Vesicoureteral reflux

Among other symptoms such as fatigue and weakness, high blood pressure, muscle aches, and frequent urination, chronic kidney disease can also cause symptoms specific to the digestive system such as nausea, vomiting, and loss of appetite.

Liquids absorbed through the walls of the small and large intestines are carried through the circulatory system into the urinary system.
Liquids absorbed through the walls of the small and large intestines are carried through the circulatory system into the urinary system.

In addition, recent studies show that chronic kidney disease also affects the body’s ability to digest food. It can cause abnormalities in digestive secretion and absorption, including the previously documented instances of toxins moving through the gut barrier and the less explored dysfunction of the upper gastrointestinal tract. 

This interaction can cause digestive issues and low bowel water.

Urinary Tract Infection

Also known as a UTI, these infections are caused by unhealthy bacteria building up in the urinary tract. These bacteria tend to spread from parts of the gastrointestinal tract to the urinary tracts.

The intestines serve to absorb nutrients as well as excrete waste.
The intestines serve to absorb nutrients as well as excrete waste.

UTIs commonly appear in the bladder (also known as cystitis) and urethra (also known as urethritis) but can show up anywhere in the urinary system. Initial symptoms include frequent urination, painful urination (commonly experienced as a “burning” sensation during urination), urine with a strong odor, urine that is bloody or cloudy, and lower abdominal pain.

Should it spread higher in the urinary tract, the infection can become more severe and begin to affect the digestive system. Symptoms that indicate a worsening UTI include high fever, body chills, nausea, vomiting, upper abdomen and back pain (also known as “flank aches”), confusion, disorientation, and agitation.

UTIs are more common in women than in men, but symptoms are the same for women and men.

Cancers

Cancers such as bladder cancer, stomach cancer, kidney cancer, and colorectal cancer can metastasize and spread from one system to another.

What Foods Are Best for the Kidneys and Bladder?

The digestive system is responsible for providing nutrients, but patients are the ones responsible for entering the healthiest and most nutrient-rich foods into their systems. A proper diet is the key to maintaining a healthy urinary system.

In addition to drinking the right amount of water — about 13 cups or 3 liters per day — the best foods for the kidney and bladder health include:

  • Bananas
  • Bell peppers
  • Blueberries
  • Cabbage
  • Cauliflower
  • Cranberries
  • Egg whites
  • Fish (sea bass, salmon, etc.)
  • Grapes
  • Macadamia nuts
  • Olive oil
  • Onions
  • Pineapples
  • Radishes
  • Turnips
  • Whole grains
  • Yogurt (plain)

These foods contain strong anti-inflammatory compounds and antioxidants, high amounts of insoluble fibers, and vitamin C, which are also essential to maintaining a healthy digestive system.

While a healthy diet can be a strong preventative, the symptoms of kidney disease can also be mitigated by a diet that is easier on the digestive and urinary systems. Low sodium and low potassium diets can also boost kidney health.

Avoid consuming too much acid, caffeine, grease, salt, saturated fat, spicy foods, or sugars.

What Other Systems Interact With the Digestive System?

Since the digestive system is responsible for providing essential nutrients to the rest of the body, the digestive system is closely connected with every other system of the body.

The circulatory system is the one that works as closely with the digestive system as the urinary system does. While the urinary system filters liquid waste from the body and prevents toxins from getting in the blood, the circulatory system takes nutrients from the food broken down by the digestive system and delivers them to the rest of the body in the bloodstream.

Can Bowel Problems Affect the Bladder?

Because the bowels and bladder are located in the same area of the body, specific problems with one organ can easily affect the other.

For instance, there are several illnesses in which the bowel cannot empty completely or properly, such as irritable bowel syndrome (IBS). Severe constipation like this causes the bowels to swell and push down on the bladder, causing problems such as anterior vaginal prolapse.

Conclusion

By now it should be clear how connected the digestive and the urinary systems are and how crucial they are to the entire body. And since diseases in these systems are no joke, it’s worth knowing how to prevent them and stay healthy.

Discussion Comments

anon333944

Remember the old saying "I got a gut feeling"? Everyone should look into the research that the stomach is made up of brain cells and can reproduce them! Amazing research.

anon333586

This is really going to help me on my school essay on the ways the digestive system and the urinary system work together.

cloudel

I know that the two systems are connected, because by eating and drinking certain things when I have a urinary tract infection, I can help my body get rid of it. Even though the infection is in the urinary tract, the food and liquid that go through the digestive tract eventually get to it.

The infection is caused by bacteria, and eating foods with high acid content helps eliminate them. I eat yogurt and pineapple for this, and I drink cranberry juice.

There is acid in the juice, but also just drinking plenty of fluids helps flush out the bacteria. I alternate between water and cranberry juice.

DylanB

I never really thought about what I eat affecting my urinary system. It's more natural to think that whatever you drink goes to the urinary tract and whatever you eat is handled by the digestive tract.

Really, it all goes together. What goes in comes out of both.

feasting

@Perdido – Yes, and lots of soda and even tea can be bad for your kidneys. I have friends who almost never drink water but chug soda all day long, and they have developed big kidney stones that were incredibly painful and required surgery.

The caffeine is just too much for the kidneys to handle. A little bit doesn't hurt, but when you don't consume any water to help your urinary system flush things out, you get a buildup of toxins in your kidneys.

Perdido
What you eat and drink affects your urinary system. I know that whenever I drink lots of tea or soda I have to urinate often. I try to avoid drinking a lot on long trips, because having to stop at a restroom every half hour or so makes the drive home a lot longer!
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    • The digestive system sends waste to the urinary system.
      By: 3drenderings
      The digestive system sends waste to the urinary system.
    • The digestive tract begins at the mouth and ends with the anus and includes all the organs in between.
      By: maya2008
      The digestive tract begins at the mouth and ends with the anus and includes all the organs in between.
    • A urologist is a medical doctor who specializes in diseases and conditions of the urinary system.
      By: Darren Baker
      A urologist is a medical doctor who specializes in diseases and conditions of the urinary system.
    • Liquids absorbed through the walls of the small and large intestines are carried through the circulatory system into the urinary system.
      By: snapgalleria
      Liquids absorbed through the walls of the small and large intestines are carried through the circulatory system into the urinary system.
    • The intestines serve to absorb nutrients as well as excrete waste.
      By: Kirill_M
      The intestines serve to absorb nutrients as well as excrete waste.