Every day, we eat to keep ourselves alive and energized. But what exactly happens to our bodies and the food we ingest? We often don't think about our digestion until, for some reason, it starts to become a problem in our lives. However, to have a healthy gut, we must first understand how this intricate process works.
Our digestion involves several processes in our body that work together as a team to break down foods and extract the essential nutrients that give our bodies the fuel needed to breathe, think, and move. The process of digestion involves both the gastrointestinal (GI) tract—made up of hollow organs like the mouth, esophagus, stomach, intestines, and anus—and solid organs like the liver, pancreas, gallbladder, and kidneys, which play critical roles in nutrient management, digestion, and waste filtration in our bodies.

Hormones & Nerves

Hormones and nerves are key players in managing digestion. They send signals to control the release of digestive juices and the movement of food through the gastrointestinal (GI) tract. Hormones, in particular, are essential for coordinating the activities of the digestive system. There are six different hormones that work together to make sure the digestive process is efficient and well-regulated. They balance the release of digestive enzymes, bile, and other substances while also managing how food moves through the digestive tract.

Nerves are just as important in digestion. They regulate the various processes involved in breaking down food, absorbing nutrients, and getting rid of waste. The nervous system ensures that digestion runs smoothly and responds to the body's needs. It keeps the balance between digestion and the body's overall physiological demands.

The Start: The Mouth

Digestion starts in the mouth, believe it or not. When you chew, food is broken down into smaller pieces and mixed with saliva. Saliva has enzymes that begin to digest starches. It's important to chew your food well because the rest of digestion depends on enzymes, acids, and bile, not physical breakdown. The mouth plays a key role in the first steps of digestion, using both mechanical and chemical methods to get food ready for deeper digestion and absorption later in the digestive tract.

The Stomach

After swallowing, food travels down the GI tract through the esophagus and into the stomach, where it mixes with digestive juices. The primary role of the stomach is to break down food into a semi-liquid form called chyme. It does this through mechanical mixing and chemical digestion, using gastric juices that contain enzymes and hydrochloric acid. The stomach aids in the initial digestion of proteins and prepares food for further digestion in the small intestine.

The Small Intestine

The small intestine follows the stomach in the digestive tract. This is where most of the digestion and nutrient absorption occurs. The small intestine is long and narrow, divided into three parts. As soon as the food arrives there, with the help of the solid organs, the longest part of digestion begins. Once completed, nutrients are absorbed through the intestinal walls into our bloodstream.

Role of Solid Organs in Digestion

As soon as food or chyme arrives in the small intestine, the following starts to happen:

Pancreas: The pancreas produces and releases digestive enzymes into the small intestine that break down carbohydrates, proteins, and fats.
Liver: The liver produces bile, which is essential for fat digestion. It also processes and stores nutrients absorbed from the small intestine, detoxifies harmful substances, and regulates energy by storing and releasing glucose.
Gallbladder: The gallbladder stores and concentrates bile produced by the liver. During digestion, especially after consuming fats, it releases bile into the small intestine to help break down fats.

The Large Intestine

Once the small intestine has done its job, it sends what’s left to the large intestine. The large intestine is responsible for absorbing the remaining material, including water, electrolytes, and the undigested food parts. It also compacts the waste into stool, which is stored in the rectum before being excreted through the anus.

Fun Fact: The large intestine is wider and shorter than the small intestine.

The Kidneys

The kidneys play a crucial role in maintaining the body's balance by filtering out waste products from the blood. After the liver processes nutrients and detoxifies harmful substances, the kidneys remove these wastes, excreting them as urine. This filtration process ensures that toxins are efficiently eliminated from the body while maintaining a healthy balance of electrolytes and fluids.

The Importance of Gut Microbiota

The gut microbiota, made up of trillions of microorganisms in our intestines, is crucial for digestive health. These bacteria help break down certain foods, make vitamins, and protect against harmful pathogens. A varied and balanced gut microbiota is key to good digestion and overall health.

By taking care of our digestive system, we can boost our quality of life and ward off many common digestive issues.

And there you have it! All these processes happen daily without us even noticing. That's why we're so passionate about gut health and digestion—our lives depend on it.

The Digestive System: A Comprehensive Guide to How Our Body Processes Food