The digestive tract is a fascinating interplay of various organs. Here, food is ingested, broken down, utilized, and absorbed, and indigestible residues are excreted. Each organ has specific functions and physiological characteristics. Digestion is divided into mechanical and chemical processes.

1. Dismantling of large structures
2. Conversion into a form suitable for absorption

We start with the oral cavity and its microbiome:

Food isn't just broken down in the mouth. Digestion also begins here, and we have our first immunological protection against everything that enters our world through the mouth. Our intestinal barrier begins with our oral barrier.

• mechanical grinding of food
• Movement of food pulp through the tongue
• Swallowing reflex
• Production of saliva, about 1 liter per day

• Pre-digestion of carbohydrates by the enzyme amylase
• Pre-digestion of fats by the enzyme lingual lipase
• Coating of the food pulp with mucus for the swallowing process
• Moisturizing the oral cavity
• Defense against viruses, bacteria and fungi
• Control of oral flora and plaque
• Neutralization of toxins
• Buffering of food acids
• Protection and remineralization of teeth
• Protection of the oral mucosa
• Regulation of the pH value
• Makes speaking easier
• Taste perception – releases flavors and delivers them to the taste buds

The functions of saliva are diverse, as are its effects on health and disease. Therefore, optimal saliva composition and production are extremely important.

• Nutrition: Our food has a major impact, both positively and negatively. It promotes or inhibits pathogenic germs, influences the pH of saliva, and influences the oral microbiome.
• Respiration – Air composition: Our air contains particles that interact with our mucous membranes. Humidity influences saliva flow, mucous membranes, and mucociliary clearance (the function of the cilia).
• Mouth/nasal breathing: Nasal breathing is the healthy norm, while mouth breathing is considered a silent nuisance – it negatively affects saliva flow, pH, and the oral microbiome.
• Alcohol: Alcohol negatively affects saliva secretion and promotes the growth of pathogenic germs.
• Smoking: Smoking impairs blood circulation to the gums, reduces saliva production, and weakens the immune system.
• Medications: Medications can cause mucosal changes, changes in pH, and a reduction in salivary flow.

The oral microbiome consists of more than 700 known species of bacteria, fungi, viruses, and archaea that colonize the mouth. A healthy oral microbiome is dynamically balanced and fulfills important functions.

• it protects us from disease-causing germs
• it produces antimicrobial substances (e.g. bacteriocins, hydrogen peroxide)
• it regulates and supports the oral immune system
• it prevents inflammations, e.g. gingivitis and periodontitis
• it helps regulate the pH of saliva
• it helps prevent tooth decay
• it helps promote metabolic health and cardiovascular balance (systemic effect via the oral mucosa)
• it helps fight infections in the upper respiratory tract
• Together with saliva, it helps prepare for healthy digestion

A disruption of the oral microbiome balance—for example, due to periodontitis—can lead to a sustained increase in the release of pro-inflammatory cytokines. These immune system messengers enter the body via saliva, the blood vessels in the gums, or through swallowing. Microbial components such as endotoxins (e.g., lipopolysaccharides, LPS) can also enter the body. These substances activate inflammatory signaling pathways, particularly via Toll-like receptors, which distinguish between "friend" and "foe." This can promote systemic low-grade inflammation.

A healthy oral microbiome is a silent but powerful ally for our systemic health. To promote and stabilize it, simple, holistic dietary and lifestyle measures are often sufficient.

1. Gentle but consistent oral hygiene

• Brush your teeth at least twice a day
• Floss once a day
• Clean your tongue
• 1-2x/year professional teeth cleaning
• Objective: to control harmful biofilms and plaque without disturbing the oral balance

2. Feed the good bacteria

• Reduced consumption of sugar and refined carbohydrates deprives pathogenic bacteria of their main food source and helps maintain a balanced pH in saliva.
• Fiber also promotes the oral microbiome
• Fermented foods contain health-promoting and sustaining microbes
• Green tea (organic) – contains antibacterial polyphenols against Streptococcus mutans
• Drink enough water
• Pro-Oral Foods*

3. Stress regulation and sleep

• Stress changes the composition of saliva
• Healthy sleep is also regenerative for the oral mucosa and the immune balance

4. Avoid smoking and excessive alcohol consumption

• Tobacco massively alters the oral microbiome – in favor of pathogenic germs
• Alcohol (especially high-proof alcohol, which can also be found in mouthwashes) disrupts the microbial symbiosis

5. Clean and humid air

• Regular exercise in the fresh air in nature
• Ventilate rooms regularly
• Avoid dry air in rooms

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