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Why Smaller, More Frequent Meals Work Better

by luciano

When you eat a very large meal, several things happen:

  • The stomach stretches significantly

  • Blood flow to the digestive system increases

  • A strong hormonal response is triggered (insulin, incretins, etc.)

This can lead to:

  • Sleepiness or drowsiness

  • Mental “fog”

  • A feeling of heaviness

Dividing total calorie intake into several moderate meals:

  • Reduces the digestive load of each single meal

  • Helps keep blood glucose more stable

  • Promotes more consistent energy throughout the day

Better several balanced meals than one very large one.

✅ “Finish eating and not feel your stomach”

This phrase describes an ideal state very well:

  • Not full

  • Not empty

  • No tension or weight

In practice: light satiety, not “fullness.”

A good indicator is stopping when you feel satisfied but could still eat a little more.

This approach:

  • Improves digestion

  • Reduces reflux and bloating

  • Supports mental focus

What causes post-meal “mental fog”

It often results from:

  • Excess calories

  • Too many simple sugars

  • Very high-fat meals

  • Heavy combinations

It’s not only about quantity, but also quality.

How to make a meal easier on the stomach

  • Moderate portions

  • Lean proteins

  • Complex carbohydrates

  • Cooked or raw vegetables in a tolerable amount

  • Chew slowly

  • Avoid large late-evening meals

⚠️ An important clarification

Eating more often does not mean eating continuously.

It’s better to think in terms of:

  • 3 main meals

  • 1–2 snacks (if needed)

The key point is: a manageable digestive load at each meal.

Difference Between Ancient and Modern Grains

by luciano

 

Science indicates that the real difference between ancient and modern wheat does not lie primarily in the total amount of protein, but rather in its quality and structural organization.

A – Scientific Evidence (CREA, University of Bologna, MDPI): Summary of Main Findings

1. Gluten Strength (W Value)

The most marked difference concerns rheological properties, meaning how dough behaves.

  • Modern Wheat:

  • Selected for strong gluten (high W, often between 200 and 400). This creates a tenacious and elastic gluten network, ideal for industrial baking and pasta-making.

  • Ancient Wheat:

  • Characterized by weak gluten (low W, often between 20 and 90). The gluten network is more fragile and less elastic, making mechanical processing more difficult but, according to some studies, making proteins more easily accessible to digestive enzymes.

2. Gliadin/Glutenin Ratio

Gluten consists mainly of two protein fractions:

  • Gliadins – responsible for extensibility and for celiac toxicity

  • Glutenins – responsible for elasticity and dough strength

MDPI research shows that ancient wheats (such as einkorn and spelt) often have a much higher gliadin/glutenin ratio than modern common wheat.

Consequence:
This explains why ancient-grain doughs are stickier and less capable of retaining fermentation gases, producing breads with lower volume.

3. Gluten Quantity and Toxicity

Contrary to popular belief, ancient grains do not necessarily contain less gluten.

  • Protein content:

  • Many ancient varieties contain higher protein levels (14–18%) than modern wheat (11–14%).

  • Celiac disease:

  • Studies from CREA and Fondazione Veronesi confirm that ancient grains contain the same toxic epitopes (and sometimes in greater quantity) as modern wheat. Therefore, they are not safe for people with celiac disease.

  • Non-Celiac Gluten Sensitivity (NCGS):

  • Some research (e.g., Prof. Spisni, University of Bologna) suggests that the different gluten structure and the presence of other compounds (such as polyphenols) in ancient grains may reduce intestinal inflammation markers in non-celiac sensitive individuals.

Synthetic Comparison Table

Feature

Ancient Grains (e.g., Senatore Cappelli, Verna)

Modern Grains (e.g., Manitoba, Creso)

Gluten strength (W)

Low (20–90)

High (200–450)

Elasticity

Very low

Very high

Digestibility (non-celiac)

Potentially higher

Standard

Yield per hectare

Low

High

Plant height

Tall (>150 cm)

Short (60–80 cm)

B – Comparative Study on Gluten Protein Composition of Ancient and Modern Wheat Species

(Geisslitz et al., 2019 – Foods, MDPI)

Study Design

  • 300 cereal samples

  • 15 cultivars per species (einkorn, emmer, spelt, durum wheat, common wheat)

  • Grown in four locations to eliminate environmental variability

Key Findings

Quantity vs Quality

Ancient species show higher total protein and gluten content than modern common wheat.

Gliadin/Glutenin Ratio

Modern wheat contains much higher glutenin levels, responsible for dough strength.
Ancient species exhibit extremely high gliadin/glutenin ratios (up to 12:1 in einkorn vs <3.8:1 in modern wheat).

Technological Weakness

This produces weak gluten incapable of forming a strong network, resulting in lower bread volume but a simpler protein structure.

Conclusion
Modern breeding did not increase gluten quantity but profoundly changed its polymeric quality to enhance industrial performance.

C – Differential Physiological Responses to Ancient vs Modern Wheat (Spisni et al., 2019)

1. The Nutritional Paradox

From a biochemical standpoint, ancient and modern wheat are very similar in macro- and micronutrients.
However, human clinical responses differ markedly.

2. Inflammatory Response and Gluten Strength

  • Modern Gluten:

  • Highly polymerized, strong, and resistant to human digestive enzymes.

  • Ancient Gluten:

  • Structurally weaker and less polymerized, therefore more easily fragmented during digestion, reducing exposure to pro-inflammatory peptides.

3. Anti-Inflammatory and Antioxidant Effects

Clinical trials show that replacing modern wheat with ancient wheat leads to:

  • Reduced pro-inflammatory cytokines (IL-6, TNF-α)

  • Improved metabolic parameters (cholesterol, blood glucose)

4. Role of the Gut Microbiota

Ancient grains promote growth of beneficial bacteria producing short-chain fatty acids (SCFAs) such as butyrate, which:

  • Strengthen the intestinal barrier

  • Reduce intestinal permeability (“leaky gut”)

5. Study Conclusions

Ancient grains are not suitable for celiac disease, but represent a superior choice for:

  • Non-celiac gluten sensitivity

  • Irritable bowel syndrome

  • Healthy individuals seeking to reduce baseline inflammation

Final Synthesis

The industrially desirable technological strength of modern wheat gluten appears to be the main factor placing stress on the digestive and immune systems.

Ancient grains do not contain less gluten—but their gluten is structurally simpler, less polymerized, and potentially more digestible, which may explain their better tolerance in many individuals.

Integrated Approach to Reducing Low-Grade Chronic Inflammation

by luciano

(Low-grade chronic inflammation is not a disease in the strict sense, but a persistent biological state that promotes the development of numerous chronic conditions. This document proposes an integrated approach aimed at modulating it through lifestyle.)

Furthermore:
In the absence of unique and definitive solutions, the most rational strategy for reducing low-grade chronic inflammation consists of adopting a lifestyle model that minimizes exposure to potentially pro-inflammatory factors* and promotes protective ones.

The importance of low-grade chronic inflammation

Although intermittent increases in inflammation are essential for survival during physical injury and infections, recent research has revealed that certain social, environmental, and lifestyle-related factors can promote chronic systemic inflammation, particularly low-grade chronic inflammation (LGCI), which in turn may lead to several diseases that, taken together, represent the leading causes of disability and mortality worldwide, such as cardiovascular diseases, cancer, diabetes mellitus, chronic kidney disease, non-alcoholic fatty liver disease, and autoimmune and neurodegenerative diseases.
(see article: https://glutenlight.eu/2025/08/21/infiammazione-cronica-basso-grado/)

This type of inflammation has multiple triggers:

Gut dysbiosis:

Alteration of the intestinal bacterial flora, which may be caused by an unbalanced diet, excessive use of antibiotics, or other toxic substances.

Unhealthy diet:

Excessive consumption of processed foods rich in refined sugars and saturated fats, which can promote inflammation.

Stress:
Chronic stress can negatively affect the immune system and increase susceptibility to inflammation.

Environmental pollution and toxins:

Exposure to chemicals present in the environment or in foods can contribute to oxidative stress and inflammation.

Smoking and alcohol:

These factors can aggravate oxidative stress and damage cells, promoting inflammation.
(see article: Oxidative stress)

Among the triggers, drug use is not mentioned because drugs are always and in any case considered to be avoided.

The integrated approach must necessarily involve the individual in all aspects of life. This is the central point: a lifestyle model must be “built.” And this model must be personalized.

Another consideration concerns the individual’s general health status, which should primarily remain “healthy,” that is, free from diseases, trauma, wounds, etc., which activate acute inflammation.

It is important to emphasize that, in the presence of acute inflammation, the biological markers used to assess low-grade chronic inflammation appear elevated, making it difficult to distinguish between the two phenomena and potentially masking improvements in LGCI.

With these clarifications, we can begin the integrated approach.

1 – Stress management

This is a very important factor, considering emerging scientific evidence regarding the gut–brain axis, a bidirectional communication system through which psychological stress, emotions, and mental states influence intestinal motility, barrier permeability, and microbiota composition, and vice versa. Alterations of this axis can promote inflammation, digestive disorders, and metabolic imbalances.
Stress should be managed either independently using available techniques or, if not possible, with the help of a psychologist.

2 – Environmental pollution (air, water, etc.)

It goes without saying that the more we can avoid it, the better. This factor is relevant to oxidative stress.

3 – Nutrition: here we can do a lot

Important point:

Diet must be strictly correlated with age, type of activity, eating habits, and general health status.

Foods to avoid

  1. Industrial foods: contain additives that, if taken occasionally and individually, do not cause problems, but if combined together may exert a more or less marked pro-inflammatory action depending on the subject’s health status [A].

  2. Industrial beverages: generally contain many sugars/sweeteners/additives.

  3. Many gluten-free products (especially industrial ones) are highly processed and contain additives (often many) that, if taken occasionally and individually, do not cause problems, but if combined together may have a pro-inflammatory action depending on the subject’s health status.

Foods to consume in moderation

  1. Wine/beer: in moderation.

  2. Alcoholic beverages: on rare occasions (spirits: NO).

  3. Coffee: in moderation.

  4. Processed meats: with great moderation.

  5. Sweets: in moderation. If there are issues with sugars (weight or glycemia), they must be consumed in appropriate amounts to avoid problems.

  6. Cheeses: with great moderation and in amounts compatible with the individual (if lactose/casein intolerant).

  7. Spices: in moderation.

  8. Fats: less trans (hydrogenated) fats and, to a lesser extent, excess saturated fats, and more extra virgin olive oil (oleic acid).

  9. Refined sugars: the less, the better. It should also be remembered that frequent spikes in glucose and insulin stimulate the production of pro-inflammatory cytokines

  10. Gluten: in moderation. If possible, whole-grain/partially whole-grain pasta; bread: if possible, whole durum wheat/spelt. Soft wheat contains a gluten component that is very difficult to digest (33-mer). Considering the relationship between gluten strength and digestibility, products made with grains that have less tenacious gluten should be preferred. Among “ancient grains,” many with this characteristic can be found (in reality, even among modern grains there are cultivars with less tenacious gluten, often used for pastries rather than bread). These should be preferred.

  11. Those who are gluten intolerant but not celiac, considering that this intolerance is “dose-dependent,” can, with the help of a physician, try to identify the threshold (quantity) that does not cause problems. Grains with less tenacious gluten facilitate the possibility of consuming products made from them. Further reading: Difference between ancient and modern grains (published separately)

Foods to consume in abundance

  1. Fiber (compatible with any intestinal issues): 3–4 times per day.

  2. Fruit (depending on any sugar-related issues: blood sugar and/or weight).

  3. Green tea: an excellent ally. Green tea is considered a powerful ally against chronic inflammation thanks to its rich composition of bioactive compounds that act on multiple fronts of the body [D].

It’s worth noting the essential contribution of water to maintaining effective hydration. The lymphatic system is a sort of drainage network for chronic inflammation.

But it only works well if there’s enough water. If you drink too little, lymph stagnates, toxins remain in the tissues, and “background” inflammation increases. See: The Role of Water in Reducing Low-Grade Inflammation

4 – Eating behaviors

Nutrition rests on two main pillars: quantity and quality.

The quantity of food consumed should be what is necessary for physiological functions plus what is required for activities performed. This simple principle would greatly help maintain a correct and healthy weight. Not easy for two simple reasons: the first is “gluttony,” the second is that the “full/satiated” mechanism is delayed compared to actual fullness; the sensation of satiety does not coincide with real stomach filling but arrives later. Already 50 years ago, family doctors suggested leaving the table with a slight desire for more food.

Quality: it goes without saying that the more genuine and “clean” (i.e., free of toxic substances) foods are, the better.

The following should also be considered a general framework because, as stated, it must be “designed around the individual.”

A – Avoid consuming too much food in a single meal

The stomach should be allowed to work (digest) optimally. It is often preferable to eat more frequently rather than having a single very large meal. Ideally, one should finish eating and “not feel the stomach,” with the result of no postprandial “fog.”
Further reading: Why smaller, distributed meals work better (published separately)

Food that is not completely digested, in healthy individuals*, is subsequently processed in the intestine and then expelled. However, if the gastrointestinal system is compromised or altered, the passage of inadequately digested substrates into the intestine may promote bacterial fermentation and be pro-inflammatory. (https://glutenlight.eu/2025/06/12/cibo-non-digerito-e-infiammazione-intestinale/)

Not only the stomach, but also and especially the intestine must be able to function optimally and continue digesting food in order to make it absorbable. [B] [C]
*The critical point here is: does a truly healthy individual still exist?

B – Avoid mixing very different foods

The stomach works in an acidic environment, where pepsin digests proteins (further digested in the intestine by trypsin and other enzymes). Sugars begin digestion in the mouth (ptyalin) and are then mainly digested in the intestine (pancreatic amylase). Some clarifications are necessary:

Carbohydrates and proteins in the stomach generally do not cause problems.
A pasta course followed by fish, meat, cheese, and perhaps vegetables, in amounts appropriate to one’s digestive capacity, does not cause problems.

If the second course is very fatty, gastric digestion slows and, depending on quantity, gastric emptying may be delayed, with possible passage of incompletely digested food into the intestine.

The situation is different if a dessert is included.

Here we face a significant amount of simple sugars, not complex carbohydrates (pasta, for example, is mainly starch, and only part of it is transformed into sugars already in the mouth; therefore, mainly starch reaches the stomach).

Sugars are not digested in the stomach except to a negligible extent:

“The stomach has a highly acidic environment that prevents fermentation there; the undigested sugars travel to the small intestine and large intestine, where they are fermented by the gut bacteria.”

Dessert at the end of a meal (intended as a moderate portion) does not cause problems in a healthy person (who today is relatively rare), but it makes digestion more difficult for many people, not only because of possible subsequent intestinal effects, but also due to the sensation of heaviness that may appear.

It should be clarified that this is not a dogma: there are people who digest practically everything without difficulty—we are all different.

Age also plays a fundamental role. Elderly individuals tend to feel better when meals are simpler.
Further reading: Sugars and proteins in gastric digestion (published separately)

Important point

In the presence of diet-related pathologies, the intervention of a specialist (dietitian or nutritionist) is strictly necessary.

5 – Specific behaviors

  1. Engage in physical activity, even moderately.

  2. If working, avoid work that leads to stress. Stress must be managed, otherwise it becomes a cause of low-grade chronic inflammation.

  3. If overweight, weight must be reduced.

  4. After work, engage in activities that require concentration and, if possible, creativity. Developing projects is highly useful for keeping brain functions active.

6 – Medical evaluations

With one’s physician, define the routine general tests necessary for good monitoring of one’s health, as well as specific tests for any conditions.

Final Summary

We must build a personalized lifestyle model for reducing low-grade chronic inflammation.
In a healthy person, a meal containing proteins and sugars in moderate amounts does not create problems. The association becomes potentially problematic when sugars are highly concentrated, especially in liquid form and in large quantities. In individuals with a sensitive or altered gastrointestinal system, even moderate portions (such as dessert at the end of a meal) may cause digestive discomfort.

The integrated approach to reducing low-grade chronic inflammation is based on the available scientific evidence reported in the bibliography section.

Since many studies show significant associations without demonstrating an absolute causal relationship, a precautionary principle is adopted: reduce or eliminate, where possible, potentially harmful factors, favoring choices with low biological risk.

The 33-mer Peptide — Why It Is a Fundamental Reference

by luciano

(Insight 2 of “Genetic Potential and Processing Conditions in the Determination of Gluten Strength, Digestibility, and Immunogenicity”)

The 33-mer peptide (sequence LQLQPFPQPQLPYPQPQLPYPQPQLPYPQPQPF) is recognized as one of the most digestion-resistant peptides derived from gluten proteins and as one of the main stimulators of T cells in the context of celiac disease.

Its importance stems from three key characteristics:

1 – Enzymatic resistance
Its high content of proline and glutamine makes it highly resistant to human digestive enzymes (pepsin, trypsin, chymotrypsin), allowing it to persist in the intestinal lumen after both in vitro and in vivo digestion.
2 – High immunogenicity
It contains multiple regions (epitopes) recognized by T cells from patients with celiac disease and was among the first peptides identified with this property.
3 – resence in common wheat species
It is present in most common hexaploid wheats (T. aestivum) and in spelt, but has been reported as absent in tetraploid/diploid wheats lacking the D genome (such as durum wheat, emmer, and einkorn).
For these reasons, the 33-mer peptide is frequently used as a marker for assessing “gluten immunogenicity” in flours and food products and for comparing wheat cultivars in research focused on immune response.

Key Findings from Studies on the 33-mer Peptide. Shan et al. (2002) — Identification and Immunogenicity of the 33-mer. Title: A resistant peptide from gliadin that is a potent activator of intestinal T cells in celiac disease. Authors: Shan L., Molberg Ø., Parrot I., Hausch F., Filiz F., Gray G.M., Sollid L.M., Khosla C. Journal: Science (2002). DOI: 10.1126/science.1074624

Core finding:
This landmark study isolated and characterized the 33-mer peptide as one of the most potent activators of T cells in celiac patients and demonstrated its extreme resistance to standard proteolytic digestion, confirming its immunogenic relevance.

Vader et al. (2002) — Structure and Epitopes of the 33-mer. Title: Structural basis for gluten intolerance in celiac sprue. Authors: Vader W., Stepniak D., Bunnik E., et al. Journal: Journal of Experimental Medicine (2002)
DOI: 10.1084/jem.20020609

Core finding:
Mapping of the major immunogenic epitopes within gliadins, explaining why sequences such as the 33-mer—with multiple and overlapping epitopes—are particularly active in triggering immune responses.

Schalk et al. (2017) — Quantification and Distribution of the 33-mer in Wheat. Title: Quantitation of the immunodominant 33-mer peptide from α-gliadin in wheat flours by liquid chromatography tandem mass spectrometry. Authors: Kathrin Schalk, Christina Lang, Herbert Wieser, Peter Koehler, Katharina Anne Scherf. Journal: Scientific Reports (2017). DOI: 10.1038/srep45092

Core finding:

This study measured the 33-mer content in a wide range of modern and ancient wheat flours using a targeted method (SIDA + LC-MS/MS), providing important data on variability among wheat genotypes.

Specific Findings from Schalk et al. (2017)

General overview:

The 33-mer peptide was detected in all common wheat (hexaploid) and spelt flours analyzed.
Reported values ranged approximately from 90.9 μg/g to 602.6 μg/g of flour.
The peptide was not detected (below limit of detection) in cereals lacking the D genome such as durum wheat, emmer, and einkorn, consistent with the absence of α2-gliadins encoding this peptide.
Interpretation:
The observed variability indicates that even within closely related wheat types, the amount of 33-mer peptide can differ substantially. This suggests that genotype and cultivar variation have a tangible impact on the content of celiac-related immunogenic peptides.

Related and Complementary Evidence

Norwig et al. (2024) confirm the presence of the 33-mer in all analyzed common wheat and spelt samples, reinforcing its central role in gluten-related peptidomic research.
Broader proteomic and peptidomic approaches show that the 33-mer is only one of several immunogenic peptides that can persist after digestion, but it remains a robust marker for comparing genotypes and technological processes (fermentation, baking, etc.).
Explanatory Box — Main Results from Schalk et al. (2017)

33-mer peptide content (μg/g flour) in analyzed wheats:

Minimum observed value: ~90.9 μg/g
Maximum observed value: ~602.6 μg/g
Typical distribution: most samples fall in the 200–400 μg/g range
Absence: not detected in durum wheat, emmer, and einkorn, likely due to the lack of D-genome α2-gliadin.

Why This Subsection Completes the Big Picture
Starting from a clear biological concept (resistance + immunogenicity), this subsection connects:

Molecular mechanisms (multiple epitopes within a single peptide),
Classical experimental evidence,
Real quantitative data across different cultivars,
Consistency with variability observed in broader peptidomic studies.
This provides readers with a solid framework to understand not only that the 33-mer exists, but why its presence and quantity vary among wheats and why it matters for digestion and immune response.

Keywords: 33-mer peptide, gluten immunogenicity, celiac disease gluten peptides, α-gliadin peptides, digestion-resistant gluten peptides, wheat cultivars immunogenicity, gluten T-cell epitopes, gluten peptidomics, wheat genetics and celiac disease, gluten digestibility

Related topics with “Chronic low-grade inflammation (or chronic silent inflammation)”

by luciano

1 – Paradigmatic cases (In depth of Chronic low-grade inflammation (or chronic silent inflammation)

Obesity

Obesity—especially visceral obesity—is accompanied by a state of chronic low-grade inflammation. Excess adipose tissue secretes pro-inflammatory cytokines (such as TNF-α and IL-6) that contribute to the development of insulin resistance. It is therefore not surprising that obese patients often show elevated levels of C-reactive protein (CRP) (a marker of systemic inflammation) and a higher risk of type 2 diabetes. Lifestyle interventions aimed at weight reduction (a balanced diet and exercise) help to “cool down” this metabolic inflammation, also improving clinical parameters.

Metabolic syndrome

Metabolic syndrome is closely associated with a state of chronic low-grade (or “silent”) inflammation, in which excess visceral fat acts as an endocrine organ by secreting pro-inflammatory cytokines (such as IL-6 and TNF-α). This persistent process—often referred to as “meta-inflammation”—promotes insulin resistance, vascular dysfunction, and increases the risk of diabetes and cardiovascular disease.

Rheumatoid arthritis (autoimmune disease)

References
Wellen & Hotamisligil, J Clin Invest, 2003
Shoelson et al., J Clin Invest, 2006

Rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease that primarily affects the joints, causing pain, swelling, and symmetrical stiffness, with onset often between 40 and 60 years of age. The immune system mistakenly attacks healthy tissues, creating chronic low-grade inflammation which, if left untreated, leads to progressive deformities and joint damage.

Biomarkers

The most commonly used markers of low-grade inflammation include C-reactive protein (CRP), interleukin-6 (IL-6), fibrinogen, and reactive oxygen species (ROS). These markers can be measured through blood tests and indicate a chronic inflammatory state that may be associated with various health conditions.

References
McInnes & Schett, NEJM, 2011
Smolen et al., Lancet, 2016

2 – Appendix A

Generalized inflammation, also known as systemic inflammation, is a condition in which the inflammatory process simultaneously involves multiple body districts rather than remaining confined to a specific site. This means that inflammatory mechanisms—normally activated as a protective response to infections, injuries, or tissue damage—remain diffusely and persistently active.

Systemic inflammation can develop in two main ways, characterized by different mechanisms, onset times, and clinical significance. On the one hand, it may result from the generalization of an initially localized acute inflammation; on the other, it may arise from the progressive extension of a low-grade chronic inflammatory state, which over time becomes systemic.

In the first case, inflammation begins at a specific site—such as pneumonia, appendicitis, or an infected wound—and rapidly spreads throughout the body. This occurs due to the massive release of inflammatory mediators, including cytokines (such as TNF-α, IL-1, IL-6), prostaglandins, and other pro-inflammatory molecules that enter the circulation, producing a generalized response. Typical examples include sepsis, septic shock, extensive burns, and major trauma. This form—known as acute systemic inflammation or SIRS (Systemic Inflammatory Response Syndrome)—is characterized by rapid onset, high intensity, and marked symptoms such as high fever, tachycardia, hypotension, and major metabolic alterations.

In the second case, inflammation is slow, persistent, and low-intensity. It initially affects one or more specific tissues—such as adipose tissue, the gut, or the joints—and later tends to spread systemically. The underlying mechanism is the continuous production of small amounts of inflammatory mediators that do not trigger an evident acute response but progressively accumulate over time. This condition is termed chronic low-grade systemic inflammation and is frequently associated with obesity, type 2 diabetes, metabolic syndrome, cardiovascular disease, and autoimmune disorders.

Among the main sites of origin of low-grade chronic inflammation, the gut plays a central role due to its large surface area, intense immune activity, and close interaction with the microbiota. Alterations in the intestinal barrier and microbial composition can promote the translocation of pro-inflammatory molecules into the bloodstream, contributing to the systemic spread of the process.

The causes of systemic inflammation—especially in its chronic form—are multiple and include chronic or recurrent infections, obesity, chronic inflammatory diseases such as rheumatoid arthritis and ulcerative colitis, chronic stress, an unbalanced diet rich in saturated fats, sugars, and ultra-processed foods, deficiencies of vitamins, minerals, and antioxidants, as well as smoking and excessive alcohol consumption.

Symptoms of generalized inflammation may vary depending on the cause and severity, but frequently include chronic fatigue, widespread muscle and joint pain, difficulties with concentration and memory, mood swings with irritability, anxiety or depression, digestive disturbances such as constipation or diarrhea, and in some cases a mild, persistent fever.

Over the long term, systemic inflammation represents an important risk factor for numerous chronic diseases, including cardiovascular disease (hypertension, atherosclerosis, myocardial infarction), type 2 diabetes, certain cancers (especially colon and breast), kidney disease, and worsening of autoimmune conditions.

In summary, systemic inflammation can reflect either an acute response that becomes generalized or the outcome of a low-grade chronic process that progressively extends. Although these are different conditions, both involve the simultaneous involvement of multiple organs and systems and have a relevant impact on overall health.

3 – Appendix B

Undigested food

Undigested food can trigger chronic low-grade inflammation, a biological process known as metabolic endotoxemia.

Here are the main mechanisms linking impaired digestion to inflammation:

1. “Leaky gut” (intestinal permeability)

When food macromolecules are not properly broken down (due to enzyme deficiency or insufficient chewing), they can damage the intestinal tight junctions.

Mechanism: Fragments of undigested proteins and bacterial toxins (LPS) pass directly into the bloodstream.
Response: The immune system recognizes these particles as “intruders,” activating a persistent but mild systemic inflammatory response.

2. Dysbiosis and fermentation

Undigested food reaching the colon becomes a substrate for fermentation by pathogenic bacteria.
Protein putrefaction: If proteins are not digested in the stomach/small intestine, their breakdown in the colon produces toxic metabolites such as ammonia and hydrogen sulfide, which irritate the intestinal mucosa and increase pro-inflammatory cytokine levels.
Excess LPS: Overgrowth of Gram-negative bacteria increases lipopolysaccharides (LPS), among the most powerful activators of low-grade inflammation detectable via hs-CRP.

3. Non–IgE-mediated food intolerances

Unlike acute allergies, constant exposure to foods the body cannot properly process (e.g., lactose or fructose malabsorption) keeps the immune system in a state of chronic alert.

Signs to monitor

If you suspect your inflammation is linked to digestion, look for:

  • Immediate or post-prandial abdominal bloating

  • Visible food fragments in the stool

  • Brain fog after meals

4 – A special case: the role of gluten

“The role of gluten: Gluten exerts multiple harmful effects that compromise human health, not only in gluten-dependent diseases but also in chronic inflammatory conditions unrelated to gluten. After consumption, indigestible gluten peptides are modified by luminal microbial transglutaminase or transported across the intestinal epithelium to interact with the densely populated immune cells of the mucosa. As disruptors of intestinal permeability, undigested gluten peptides compromise the integrity of tight junctions, allowing foreign immunogenic molecules to reach internal compartments. Gliadin peptides are systemically distributed to remote organs, where they encounter endogenous tissue transglutaminase. Following post-translational deamidation or transamidation, the peptides become immunogenic and pro-inflammatory, inducing organ dysfunction and pathology. Cross-reactivity and sequence homology between gluten/gliadin peptides and human epitopes may contribute to molecular mimicry in the induction of autoimmunity. As proof of concept, gluten withdrawal alleviates disease activity in chronic inflammatory, metabolic, and autoimmune conditions, and even in neurodegeneration. We recommend combining a gluten-free diet with the Mediterranean diet to leverage the advantages of both. Before recommending gluten withdrawal for non–gluten-dependent conditions, patients should be asked about intestinal symptoms and screened for celiac-associated antibodies. The current list of gluten-induced diseases includes celiac disease, dermatitis herpetiformis, gluten ataxia, wheat allergy, and non-celiac gluten sensitivity. Given that gluten is a universal pro-inflammatory molecule, other non-celiac autoinflammatory and neurodegenerative conditions should be investigated for potential gluten elimination.” Gluten is a Proinflammatory Inducer of Autoimmunity. Aaron Lerner et al. Journal of Translational Gastroenterology 2024; 2(2):109–124. DOI: 10.14218/JTG.2023.00060.

Bibliographic references

  1. Furman D, et al. Chronic inflammation in the etiology of disease across the life span. Nature Medicine. 2019.
    A landmark review describing systemic chronic inflammation as a central trait in the major causes of global morbidity (cancer, cardiovascular disease, diabetes, chronic kidney disease, and others) and discussing social, environmental, and biological drivers.

  2. Franceschi C, et al. Inflamm-aging and immune-metabolic changes with aging. Cell. 2018.
    This article introduces the concept of inflammaging—age-associated low-grade chronic inflammation—and highlights the role of persistent inflammatory mediators.

  3. Khanna D, Khanna S, et al. Obesity: A chronic low-grade inflammation and its markers. Journal of Inflammation Research. 2020.
    A review analyzing obesity as a paradigmatic model of low-grade systemic inflammation, with extensive discussion of key inflammatory markers produced by adipose tissue.

  4. Chen L, et al. Inflammatory responses and inflammation-associated diseases in organs. Journal of Biomedical Research. 2017.
    A comprehensive review of the molecular mechanisms of acute and chronic inflammatory responses and their implications in multiple systemic diseases (cardiovascular, metabolic, autoimmune, and neoplastic).