We all know that our body requires food in order to survive. This is because its needs to absorb the essential micronutrients, macronutrients and minerals that are present in various food products. At the same time, it is also important for the body to discard out any excess, unrequired or undigested food out of the body.
Thus, the digestive system is one that serves this exact purpose. It breakdowns food products into monomers that our body can absorb and then excretes out the necessary products in the form of bowels.
If the digestive system is damaged or infected, these essential functions get compromised and this condition is known as a digestive disease.
Some important terms:
Ingestion – The intake of food from the mouth by swallowing.
Digestion – The process by which the food is broken down into its small components in order for the body to successfully absorb it.
Absorption – The process by which food is absorbed into the blood and lymph vessels and is transported to the other parts of the body.
Defecation – The discharge of undigested food from the body.
Digestive System: Classification, Function and Structure
When food is ingested through the mouth, nutrients get absorbed and eventually the excess food or roughage has to be excreted out through the anus.
The pathway of food from the time of ingestion to excretion is known as the gastrointestinal tract.
The pathway consists of the following organs that perform specific functions:
Caption : Pathway of the digestive system
The gastrointestinal tract typically consists of four layers of specialised tissues: Muscosa, submucosa, muscle and serosa.
Credits : Wikipedia Caption : Four layers of the gastrointestinal tract
The mucosal layer is the layer that comes in direct contact with the food. The tissue cells perform many functions like secreting mucus and forming folded structures called villi that increase the surface area for maximum absorption of nutrients, especially in the stomach and small intestine.
The submucosal layer consists of a dense and non-uniform layer of connective tissues that contain important lymph and blood vessels. It also provides mechanical support and structure to the tracts.
The main function of the muscular layer is to perform peristalsis, the involuntary movement of muscles that pushes through the gastrointestinal tract and prevents the food from moving backwards. It also helps in the formation and movement of bowels.
The serosa is the outermost layer and consists of a smooth layer that reduces friction when the tract is in contact with each other or other organs.
Organs of the Digestive System
The difference between these organs and the gastrointestinal tract is that they are hollow or contain the four specialized layers. However, they play an important role in digestion.
It secretes enzymes into the stomach to digest fats, carbohydrates and proteins.
It also secrete insulin to help in metabolic function.
The main function of the liver in the digestive system is to further digest the absorbed food from the small intestine by secreting a substance known as bile juice, especially to digest fats and vitamins.
Once digested and absorbed the body converts these substances that the body needs to function.
Further, it destroys any chemical that can be harmful to the body and is known as the ” purifier”.
It simply stores excess bile from the liver which is released when required.
Credits: unsplash Caption : Uneasiness due to a digestive disease.
Common Symptoms For Digestive Disease
They are the following:
Pain in the stomach and abdomen
Blood in the stool
Types of Digestive Disease
Gastroesophageal reflux Disease (Gerd)
The stomach produces acids to digest fats, carbohydrates and proteins. The muscular layer of the gastrointestinal tract typically ensures that this acid does not flow backflows into the esophagus and into the mouth.
However, GERD is a condition when this acid backflows into these tubes and disturbs the esophagus. This experience is known as “acid reflux”.
There is a sphincter that guards the opening of the esophagus into the stomach that usually opens and relaxes in time of swallowing and closes after.
GERD is caused when there is an abnormality in the regulation of this function when the sphincter continues to be opened.
This causes damage and soreness to the esophageal wall and could even trigger cancer. As a result, the person will suffer from heartburns, chest pains, swallowing problems and taste sourness due to the acid.
GERDs can be cured with administered medications. In some cases, surgery is performed where the doctors mechanically try to tighten the sphincter muscle.
Credits: Wikimedia Commons Caption : Acid reflux in GERD
It is a condition in which the bile stored in the gallbladder gets converted into a hardened mass or crystal giving it the name “gallstones”.
The main cause of gallstones is usually when there is an excess amount of cholesterol in the body, leading to increased cholesterol in the bile juice and as a result, yellow stones are formed.
The liver also produces a substance known as bilirubin to destroy old red blood cells. Sometimes, if bilirubin is produced in excess, it could also lead to the formation of gallstones.
Lastly, if the gallbladder is not regularly used, the old bile starts to get over-concentrated and form gallstones.
These gallstones are usually passed during excretion. Sometimes, they are surgically removed when it is too painful to urinate or during the passage of stool.
Credits : Wikimedia Commons Caption : Gallstones
This is a condition where the mucosal lining of the stomach gets inflamed and infected.
The inner lining is extremely important for absorption, digestion and secretion of digestive substances.
There are various causes of gastritis including infection by bacteria and viruses or during bile reflux, when bile flows backwards in the stomach. Sometimes, it can also be inflamed due to injuries.
As a result, a person will experience excessive hiccups, pain, bloating, burning sensation in the stomach, vomiting of blood and nausea.
Antacids and antibiotics are used to treat gastritis.
In some cases, vitamin B12 shots are given in case of pernicious anaemia.
Credits : pixabay Caption : Bloating due to Gastritis
Gluten is a protein that is commonly found in grains like wheat, rye and barley.
Celiac disease is an autoimmune disorder and is triggered when gluten is consumed. Here, the protein is absorbed into the villi of the mucosal layer, the immune cells start attacking the villi, which means the body is attacking itself.
Since the villi is responsible for absorbing important nutrients in the stomach and intestine, it’s damage can cause malnourishment, malnutrition and other sorts of deficiencies.
The person suffering will show symptoms of gas, heartburn, anaemia, mouth ulcer and loss of bone density besides the common digestive disease symptoms.
It could also lead to inferiority and nervous disorders like seizures.
Currently, there is no cure for this disease. Patients are required to remove any gluten products in their diet.
Supplements can be given when the villi gets damaged as the body cannot naturally absorb nutrients.
Credits : Wikipedia Caption: Harmless pathogen in the gut that the immune cells attack during inflammatory bowel disease.
Inflammatory bowel disease
This disease is caused due to inflammation in the digestive tract, most commonly, in intestines.
The cause of bowel disease is still not clear. Some research claims that it is an autoimmune disease where the immune cells attack the digestive tract and causes inflammation and others claim that it is caused when the immune cells attack the harmless pathogens present in the gut.
Inflammatory bowel disease consists of two major types: Crohn’s disease and Ulcerative colitis.
The difference between the two is that ulcerative colitis is only restricted to the intestines and colon whereas crohn’s disease can affect any part of the gastrointestinal tract, from mouth to anus.
The person suffering will show distinct symptoms of excessive bowel movements, abdominal cramp and pain, fever and iron deficiency, besides the common digestive disease symptoms.
As a result, the patient will have ulcers, obstruction of the bowel and suffer from malnutrition.
Dietary changes are made to avoid malnutrition and medical treatments are aimed at suppressing the abnormal inflammation and promote healing in the gastrointestinal tract.
Credit: Wikimedia Commons
Irritable bowel syndrome (IBS)
It is a condition that affects the large intestine which leads to abdominal pain, cramping, bloating, diarrhea, constipation, gas etc.
There are different causes of IBS including conditions when:
The muscular layer of the gastrointestinal tract km the intestine abnormally contracts.
When the nervous system caused abnormalities in the digestive system.
When the gastrointestinal tract gets infected and causes inflammation.
Other triggering substances like food intolerance, hormones, tension, stress etc.
Treatments include medication like anti-diarrheal, laxative, nerve pain medication, dietary supplements and antibiotics.
A good diet must also be maintained.
Moreover, the person must practice mental health care and join psychology therapy to control stress which is one of the biggest triggers of IBS.
The anal canal contains cushions and important blood vessels.
Haemorrhoids is a condition in which the blood vessels and the anal canal abnormally swells, gets enlarged and inflammation occurs.
It is also commonly known as piles and it is extremely painful.
The main symptoms of piles are bleeding during excretion and when the internal tissues of the anal buldge out during excretion, making it very painful and sometimes unbearable.
Pile can be caused by excessive pushing during excretion, eating spicy foods, obesity, low roughage diet and anal sex.
The person will often experience constipation and vomiting.
Medications are administered to relieve pain and swelling.
In chronic cases, surgery is performed to fix the abnormality by usually removing the bulging tissue.
It is a condition in which structural pouches are formed in the intestines due to an infection or inflammation.
These structures are known as diverticulosis and are usually harmless.
However, if the infection spreads or gets prolonged, it could lead to severe conditions.
Besides infection, other causes of diverticulitis include consumption of drugs, high fat diet, obesity and smoking.
It leads to the formation of pus abscess, scarring of the intestine and formation of harmful fistulas.
It includes liquid diet until the problem passes, antibiotics to fight the infection and sometimes the surgical removal of fistulas or abscess.
Credits : Unsplash Caption : Excruciating pain due to anal fissure
It is a condition where the lining of the anus gets damaged due to cuts or tears which usually damages the muscle anal sphincter that controls bowel movements during excretion.
The condition causes the muscles to spasm and cause severe pain.
Anal fissure is caused due to the passage of large or hard stools, anal sex or constipation by causing strain.
Sometimes, sexual diseases like HIV, syphilis and herpes can also cause anal fissure.
As a result, the person will feel excruciating pain during excretion, bleeding, visible damage around the anus skin and burning sensation near the anal area.
It is usually not a serious condition. Most of the time, the anal lining heals on its own.
Medications are given to soften stools to ensure easy and painless passage, ointments are used to ease out inflammation.
In exceptional cases, botox injections are given to eliminate muscle spasm for the proper function of the sphincter.
Lastly, the anal area must be kept dry to ensure quick healing.
Credits: unsplash Caption: Healthy eating habits to prevent digestive problems.
Ensure slow and proper chewing and swallowing of food.
Avoid foods like apples, broccoli, dairy, onions and peaches that cause gas.
Avoid sweeteners and soda drinks.
Reduce the intake of fatty foods.
Maintain a fixed meal schedule and eat regularly.
Avoid overeating and lying down after a meal.
Maintain fitness to avoid obesity.