11 Body Systems: How The Digestive System Works
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11 Body Systems: How The Digestive System Works

11 Body Systems Author_Cliff-Harvey Education

The 11 Body Systems are a collection of organ systems made up of parts that are able to work together to serve a common purpose – growth, reproduction and survival.

Each part of a system depends on the other parts to perform tasks that can’t be achieved by single parts acting alone and help to improve our chances of survival by maintaining a stable internal body environment.

This stable environment is known as homeostasis. Our series, 11 Body Systems goes into depth about each body system and how it relates to the rest of the body.

Why is the digestive system important?

The digestive system is an external organ (because it is exposed to the environment) and is the route by which we absorb the nutrients that make up the body‘s structures, messengers, and fuels.

It is also a potential site of infection from pathogens in food and water and so, is a barrier defense and has a large interplay with the immune system of the body.

An important part of both the absorption of nutrients and the immune and defense role of the digestive system is the microbiome of the gastrointestinal tract which consists of both beneficial and pathogenic bacteria, fungus, protozoa, viruses which, when in balance, helps us to preserve health.

Digestion involves the breaking down of food into smaller components which can then be absorbed into the body.

The process begins with mechanical digestion (chewing, swallowing, and churning) and chemical digestion involving acids and enzymes which breakdown large molecules in food to enable absorption into the body.

What is it made up of?

The digestive system includes the mouth, oesophagus, stomach, and the small and large intestine.

It also includes accessory organs of digestion (the tongue, salivary glands, pancreas, liver, and gallbladder).

How can I support the digestive system? - Digestion supporting ingredients in Nuzest Good Green Vitality


Probiotic supplementation can reduce diarrhea, gastrointestinal pain and bloating, and symptoms of lactose intolerance, (1, 2) and inflammatory bowel disease. (3) Probiotics also help to treat constipation. (4, 5)

Specifically, L. acidophilus and Bifidobacterium species are able to bind with food-borne toxins like aflatoxin (from mould grown on food), effectively eliminating them from the body, (6) and also compete with and aid resistance to common food-borne pathogens like E. coli, Staphylococcus aureus, Listeria monocytogenes, Vibrio parahaemolyticus, Vibrio cholerae, Helicobacter pylori, Klebsiella, Salmonella, Shigella, Clostridium, and Candida. (7)

Interestingly, the combination of probiotics with plant phenols (like those found in Good Green Vitality) provides synergistic benefits, with greater survival, adhesion, and maintenance of beneficial bacteria and improved health benefits. (8)

Prebiotics, soluble fibre, and resistant starch

Apple pectin, in particular, has shown benefits for the improvement of bacterial status and increased production of beneficial short-chain fatty acids in the gut, (9, 10) and reduced incidence of colon tumours. (11)

Digestive and ‘tonic‘ herbs

Digestive and ‘tonic‘ herbs and vegetables are typically ‘bitter greens‘ that have a long history of traditional use for encouraging more effective digestion. They are also very nourishing themselves.

Dandelion has a long history of medicinal use and is known to be a very nutritious herb-vegetable. Ongoing research suggests that dandelion has anti-inflammatory, antioxidant, and potential anti-cancer applications which demand additional research. (13, 14)

Ginger is also a tonic herb. The main role for which ginger has been studied is for reducing nausea. (15) and specifically nausea during pregnancy. (16-18)

The adaptogen (stress-modulating) herb Astragalus offers protection against intestinal inflammation, and the potential effects on reducing intestinal cancers are now being researched. (19)

Soothing herbs

Some traditional herbs are known for their soothing properties, helping to quench inflammation and pain in the gastrointestinal tract.

Slippery elm is considered soothing and anti-inflammatory and these properties are thought to aid digestive difficulties. (20, 21)

Anti-inflammatory spices

Human trials suggest a role for turmeric in reducing inflammation and possibly aiding the incidence of cancer (in the gastrointestinal tract) resulting from inflammation. (22, 23)

Gut-supporting vegetables, berries, and fruits

Many health benefits are claimed for wheat grass. As a nutrient-rich food, it is likely to help support general nutrition and health.

Laboratory studies in animals are beginning to show additional clinical benefits and it offers promise for the adjunctive treatment of cancer, reducing effects of chemotherapy, along with improved immune responses and reduced oxidation.

There might also be benefits from wheat grass for a diverse range of conditions, from IBDs to rheumatoid arthritis, diabetes and obesity. (24)

Pre-clinical trials also provide evidence for the traditional use of the fruit Rosehip improved gastrointestinal health. (25, 26)

Gut-supporting minerals

Zinc is important to help close ‘tight junctions‘ in the gut wall that reduce the ability of pathogens and allergens entering the body.

A combination of supplements including zinc has been shown to improve immune responses to LPS in those with chronic fatigue syndrome. (27)

Zinc supplementation might also improve intestinal permeability (leaky gut) in inflammatory bowel disease. (28)

Food-based digestive enzymes

Pineapples and other tropical fruit have long been considered digestive aids in traditional medicine systems. Bromelain is now thought to aid protein digestion and be anti-inflammatory.


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