Intestinal Metaplasia Causes and Prevention

Intestinal Metaplasia Causes​

Intestinal metaplasia (IM) is a condition whereby the mucosa of stomach or esophagus transforms to intestinal type of mucosa. This is a precancerous condition to an extent that the patient is likely to develop stomach or esophagus cancer at some stage in their life cycle. The root or underlying factors and the risk factors include:

• Helicobacter pylori (H. pylori) Infection
• Chronic Gastritis (Long-Term Stomach Inflammation)
• Gastroesophageal Reflux Disease (GERD) and Barrett’s Esophagus
• Diet and Lifestyle Factors
• Genetic Factors
• Autoimmune Gastritis
• Bile Reflux

Intestinal Metaplasia Prevention​

Intestinal metaplasia (IM) may thus be prevented by management of the predisposing factors as well as the risk factors that are known to cause IM. Following are some of the ways in which prevention of the mentioned diseases can be done:

• Eradicate H. pylori Infection
• Follow a Healthy Diet
• Manage Acid Reflux & GERD
• Limit Alcohol & Quit Smoking
• Maintain a Healthy Weight
• Reduce Chronic Gastritis & Inflammation
• Regular Health Check-ups

Dietary Factors in Intestinal Metaplasia​

Diet as a prevention and treatment factor is considered to have a significant impact on the modification of intestinal metaplasia (IM). Here is a general breakdown of the dietary factors for IM:

Antioxidant-Rich Foods (Reduce Oxidative Damage)

• Fruits: Berry products, tropical and subtropical fruits such as oranges, lemons, apples, pomegranates
• Vegetables: Carrots, bell peppers, spinach, kale
• Herbs & Spices: Turmeric, ginger, garlic

High Fiber Foods 

• Whole grains: Brown rice, quinoa, oats
• Legumes: Lentils, chickpeas, beans
• Nuts & Seeds: Flaxseeds, chia seeds, almonds

Probiotic-Rich Foods (Improve Gut Flora & Reduce H. pylori)

• Yogurt (if tolerated), kefir
• Fermented foods: Sauerkraut, kimchi, miso

Vitamin C & E Foods (Protect the Stomach Lining)

• Vitamin C: Guava, bell peppers, broccoli, tomatoes
• Vitamin E is found in sunflower seeds, almonds, avocados and many others.

Healthy Fats (Reduce Inflammation)

• Extra virgin olive oil, nuts, seeds, avocados
• Fatty fish (if non-vegetarian): Salmon, mackerel

Smoking and Intestinal Metaplasia Risk​

There is evidence suggesting the correlation between smoking and IM development, and it is a potent risk factor for advanced diseases, including gastric cancer. The following are the elements through which smoking enhances the risk:

Increases Stomach Lining Damage

• Smoking brings such carcinogenic substances like nitrosamines and benzopyrenes, which cause injury of the gastric mucosa and promote inflammation.
• This damage weakens the defense that is offered by the stomach lining which increases its susceptibility to metaplastic transformations.

Worsens H. pylori Infection

• Smoking has adverse effects that directly results in reduced resistance of the stomach lining to IM’s primary bacterial causing agent, the Helicobacter pylori (H. pylori).
• Non-smokers are of lower risk of having Gastric cancer if they don’t have Helicobacter pylori bacteria with them.

Reduces Stomach’s Natural Defense Mechanisms

• Common side effects of smoking are decrease in the secretion of stomach mucus.
• It causes constriction of blood vessels, which have a negative effect on the distribution of blood to the stomach contributing to the slow healing in cases of injuries to the tissue layers.

Increases Acid Reflux & Barrett’s Esophagus Risk

• Smoking causes the lower esophageal sphincter to become weak hence permitting acid to flow back into the esophagus.
• Complication of reflux disease is Barrett’s esophagus which is referred to as intestinal metaplasia in the esophagus can result to esophageal cancer.

Raises the Risk of Stomach Cancer

• It should be noted that long-term smoking is associated with a 2-3 times increased risk of gastric cancer in those diagnosed with intestinal metaplasia.
• Smoking in conjunction with poor food intake, alcohol intake and Helicobacter pylori increases the rate at which one gets attacked by cancer.

Genetic Predisposition to Intestinal Metaplasia​

Intestinal metaplasia (IM) is known to be triggered by H. pylori infection, chronic gastritis, diet, smoking and heredity factors which determine one’s predisposition to the disease.

Family History of Gastric Conditions

• Patients with such history of gastric cancer or intestinal metaplasia are at a higher risk of developing IM.
• Some of these may include defects in genes controlling inflammation and gastric cell renewal.

Genetic variants associated with IM Risk

IL-1β (Interleukin-1 Beta) Gene Mutation

• Increases stomach inflammation and acid suppression.
• It is, therefore, associated with a higher risk of H. pylori, IM and gastric cancer.

CDH1 (E-Cadherin) Gene Mutation

• It influences cell adhesion which makes the possibilities of changing the stomach lining more probable.
• Alterations in the CDH1 gene that encodes for Cadherin, type 1, R-cadherin for example, cause hereditary diffuse gastric cancer and may cause IM.

MUC1 Gene Variant

Has a function of preventing the lining of the stomach to be infected by bacteria.
It has been shown that certain genetic changes may make a person more vulnerable to developing H. pylori related inflammation and hence metaplasia.

Ethnic & Regional Factors

• For instance, IM is more common in East Asian and Latin Americans mainly due to polymorphic genes associated with inflammation.

Autoimmune Gastritis & IM

• Autoimmune diseases such as autoimmune gastritis which involve over-activity of the immune system against stomach cells raise IM risk.
• Patients with autoimmune disease, such as pernicious anaemia, may have a genetic set-up to inflammation that predisposes them to IM.

Role of Chronic Gastritis in Intestinal Metaplasia​

Chronic inflammation of the gastric mucosa is one of the primary predisposing factors to develop IM because it leads to malignant transformations of the lining cells.

How Chronic Gastritis Leads to Intestinal Metaplasia

• Chronic Inflammation: The constant increase in the inflammation undercuts the lining of the stomach.
• Cellular damage and repair failure: Prolonged damage and repair end up in change of the cell’s structure.
• Metaplastic Changes: It has indicated the ability of the stomach lining to undergo change and start taking up some features of the intestinal lining as a means of adaptation.

Impact of Acid Reflux on Intestinal Metaplasia​

Acid reflux especially in GERD has been strongly implicated and has been associated with IM in the esophagus called Barrett’s esophagus or intestinal metaplasia in the stomach.

How Acid Reflux Leads to Intestinal Metaplasia

• Effects of Stomach Acid: Stomach acid and bile harmfully erode the esophagus and the lining of the stomach.
• Chronic inflammation & damage: Healing process starts; however, due to repeated injuries tissues undergo modifications.
• Cellular Adaptation (Metaplasia): The normal lining transforms into the type of cells that exist in the small intestine in an attempt to create a resistant lining to further abuse of acid.

There are various types of IM that can be attributed to acid reflux, and they are as follows;

Barrett’s Esophagus (Esophageal Intestinal Metaplasia)

• It also comes up when the acid found in the stomach harm the lower part of the esophagus.
• A major risk factor for esophageal adenocarcinoma (cancer).

Gastric Intestinal Metaplasia

• The use of Acid reduces the lining of the stomach, thus causing inflammation.
• In due course, it results in the alteration of the intestinal type of the stomach.

Alcohol Consumption and Intestinal Metaplasia​

Drinking alcohol raises the possibility of developing intestinal metaplasia because it harms the lining of the stomach thus aggravating the inflammation. It is particularly destructive if there is H. pylori infection, smoking or acid reflux.

How Alcohol Contributes to Intestinal Metaplasia

• Irritates the Stomach Lining: Alcohol reduces the production of stomach layer that prevents it from being attacked by acid.
• Promotes Gastric Inflammation: This result to gastritis which is one of the main causes of IM.
• Worsens H. pylori Infections: Alcohol also changes the balance of bacteria in the stomach and turns H. pylori infections into a more dangerous form that leads to IM.
• This result in acid reflux: alcohol weakens the lower esophageal sphincter (LES) — and will lead to the development of Barrett’s esophagus (esophageal IM).
• Cancer: The long-term effects of alcohol consumption are the development of cancer; particularly gastric and esophageal cancer in individuals with IM.

High Salt Intake and Intestinal Metaplasia​

It is attributed that high salt intake contributes to IM and Gastric Cancer where the risks are boosted by H. pylori infection, smoking, and alcohol drinking.

How High Salt Intake Contributes to Intestinal Metaplasia

• Harms the lining of the stomach: High amount of salt reduces thickness of the mucus layer on the stomach thereby increasing its susceptibility to acid and inflammation.
• Causes IM: Continuation of irritation raises chances of chronic Gastritis which plays a major role in the formation of IM.
• Promotes H. pylori growth: High salt intake also increases the virulence of H. pylori making the resulting stomach damage happens more rapidly as well as the progression of IM.
• Promotes Cancerous Changes: Ingestion of salt damages the DNA in the stomach walls and makes them liable to cancers such as the gastric cancer.

Importance of Fruits and Vegetables in Intestinal Metaplasia Prevention

Appropriate intake of fruits and vegetables is useful in the prevention, management and perhaps even eradication of IM. These foods contain anti-cancer, antioxidant, and fibre along with anti-inflammatory properties would help reduce the chances of development of gastric cancer.

How fruits and vegetables prevent IM

Neutralize Stomach Inflammation

• Having antioxidant properties especially vitamin A, C and E, flavonoids, polyphenols that help to neutralize free radicals that would harm the stomach cells.
• Slows down the development of chronic gastritis to IM.

Support Stomach Lining Repair

• Rich in dietary fiber that makes it suitable and effective in fixing the stomach lining.

Inhibit H. pylori Bacteria

• Some fruits & vegetables produce individual anti H. pylori compounds that inhibit the development of IM and other gastric ulcers.

Reduce Acid Reflux & Protect the Esophagus

• These can enhance the production of zinc in the body and regulate the acid formation in stomach to reduce chances of Barrett’s esophagus (IM in the esophagus).

Preventing Stomach Cancer

• Increased intake of cruciferous vegetables, leafy green and citrus fruits are found to be inversely proportional to IM risk of progression to gastric cancer.

Lifestyle Modifications to Prevent Intestinal Metaplasia​

Possessing an overall healthy diet, practicing ways of reducing stress, and avoiding factors that cause the healing of the intestinal lining is one of the ways of trying to prevent one from developing IM. Here are main most important changes to adopt:

• Improve Your Diet
• Stop Smoking & Limit Alcohol
• Manage Acid Reflux
• Treat H.pylori Infections Promptly
• Maintain a Healthy Weight
• Reduce Stress & Improve Sleep
• Get Regular Medical Check-ups

Environmental Pollutants and Intestinal Metaplasia Risk

Environmental Pollutants can lead to intestinal metaplasia (IM) by promotion of inflammation, stress on the oxidant and on DNA of the inner lining of the stomach. These pollutants include: Air, water borne pollutants, food borne pollutants and pollutants from workplace.

Environmental pollutants play an active role as they facilitate the occurrence of IM through the following ways:

• Promoters of Oxidative Stress and Inflammation: This causes chronic irritation of the stomach walls and mutation of cells, thus resulting in gastritis.
• Disrupt Gut Microbiota: Airborne particles negatively influence the gut microbiota, including bacteria in the stomach which increases the risk of infection by H. pylori through contaminate foods.
• Trigger Acid Reflux: Some pollutants aggravate GERD, which is associated with Barret esophagus (IM in the esophagus).
• Promote H. pylori Growth: Heavy metals can contribute to the degradation of the immunity of the stomach thereby facilitating the growth of H. pylori as well as the pesticides.