Ever wondered what happens after that first bite? The journey of digestion is a complex process involving multiple organs that break down food, absorb nutrients, and eliminate waste.
As gut health experts, we focus on how your digestive system plays a crucial role in your overall health, impacting digestion, immunity, energy, skin health, mood and more (you can read more about this here). Your gut, often referred to as your gastrointestinal tract, includes your entire digestive system: your mouth, oesophagus, stomach, small intestine, large intestine (colon), rectum, and anus.1https://www.cancer.gov/publications/dictionaries/cancer-terms/def/digestive-system#
We’re here to guide you through this process and share tips for maintaining a happy and healthy digestive system. Here is an overview of the main stages of digestion:2https://www.ncbi.nlm.nih.gov/books/NBK597379/
Mouth
The digestive journey begins in your mouth, where food is taken in, this process is called ingestion. Next, mechanical digestion occurs as your teeth chew (masticate) food into smaller pieces. Meanwhile, chemical digestion begins with your salivary glands producing saliva that contains enzymes like amylase, which starts breaking down carbohydrates.
Did you know that your mouth has its own unique microbiome? Your oral microbiome plays a crucial role in maintaining oral health and supporting digestion by balancing beneficial bacteria. Check out oral microbiome – your mouth and your gut are connected!
Oesophagus
Next, your tongue pushes the chewed food (known as a bolus) to the back of the mouth, initiating swallowing. The bolus then travels down your oesophagus, which connects your mouth and stomach, through coordinated muscle contractions known as peristalsis.
Stomach
Your stomach acts as a storage tank and mixes your food with gastric juices (hydrochloric acid and the enzyme pepsin), and chemical digestion begins as these gastric juices break down proteins into smaller peptides. More mechanical digestion occurs as your stomach muscles churn the food, further breaking it down into a semi-liquid substance called chyme.
Small intestine
Chyme enters your duodenum, the first part of your small intestine, where it mixes with bile from the liver and gallbladder, and pancreatic juices from the pancreas. Bile emulsifies fats, while pancreatic juices contain enzymes that digest carbohydrates into simple sugars, proteins into amino acids, and fats into fatty acids and glycerol.
Jejunum and ileum are parts of your small intestine that are responsible for the absorption of nutrients. The inner walls of the small intestine are lined with villi and microvilli, which increase the surface area for absorption. Nutrients are absorbed through the walls of your small intestine into your bloodstream where they are transported to organs such as your liver for processing, storing, or distributing to the rest of your body.
Large intestine
The remaining undigested food passes into the large intestine, where water and electrolytes are absorbed. Here the leftover waste becomes more solid, forming faeces.
Your gut microbiome is primarily located here in your large intestine and, to a lesser extent, the small intestine. It also interacts with other organs of the digestive system, including your stomach.3https://ods.od.nih.gov/factsheets/Probiotics-HealthProfessional/ Your gut microbiome is host to a complex community of microorganisms, including bacteria, viruses and fungi, which play a crucial role in digestion, nutrient absorption, and overall health. Interested to learn more? Check out this article – how your gut microbiome is like a garden.
Rectum and anus
Finally, faeces are stored in your rectum until they are ready to be expelled during defecation.
The journey of digestion is a coordinated effort between different organs, microbiomes and systems, ensuring that the body efficiently breaks down food, absorbs essential nutrients, and eliminates waste.
Check out the signs of an unhappy gut – and what to do about it!
Any questions? Contact one of our Nutritional Therapists via live chat, we’re available on weekdays from 8am to 8pm.
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