The Digestive System and Diet

The Digestive System

The digestive system’s primary function is to break down food into smaller molecules so they can be absorbed into the bloodstream.
It consists of the mouth, oesophagus, stomach, small intestine, large intestine (colon), rectum, and anus, along with associated glands.
Digestion begins in the mouth where food is broken down by chewing and enzymes in saliva start to break down starches.
The oesophagus propels food from the mouth to the stomach using muscular contractions called peristalsis.
The stomach secretes strong acids and enzymes for protein breakdown.
Partially digested food called chyme moves from the stomach to the small intestine where the release of further enzymes assists digestion.
The body’s major organ for absorption of nutrients is the small intestine. It has a large surface area due to villi and microvilli that increase the rate of nutrient absorption.
Excess water and electrolytes are reabsorbed back into the body in the large intestine.
The rectum serves as a temporary storage site for faecal matter which is eventually eliminated from the body through the anus.

A healthy diet sustains the digestive system. Fibre, including fruits, vegetables and whole grains, helps move food through the digestive tract.
Protein is crucial for organ health, including the tissues and cells of the digestive system.
Fats should be included but in moderation. Unsaturated fats are beneficial for heart health and aid in the absorption of vitamins.
Vitamins and minerals aid various metabolic processes throughout the digestive system.
Hydration is essential to maintain the mucosal lining in the intestines, aid food breakdown and prevent constipation.
A diet low in fibre and high in fats, sugar and salt can lead to digestive disorders such as gastro-oesophageal reflux disease (GORD), irritable bowel syndrome (IBS), and even colon cancer.

Coeliac Disease affects the small intestine and is caused by an adverse reaction to gluten.
Crohn’s Disease and ulcerative colitis are chronic conditions that cause inflammation of sections of the digestive system.
A gallstone is a pebble-like deposit that forms in the gallbladder which may cause severe abdominal pain.
Gastroenteritis is an inflammation of the stomach and intestines usually caused by an infection.
Hernias occur when an organ pushes through an opening in the muscle or tissue that holds it in place. The most common types are inguinal (inner groin), incisional (resulting from an incision), femoral (outer groin), umbilical (belly button), and hiatal (upper stomach).