Inflammation: Types, causes, signs and symptoms, treatment

The general belief is that inflammation is bad. But, that's not true. Inflammation is a natural body response against harmful stimuli such as infections, irritants and injury. Learn more in this article.

A man wearing an eye glass crying, holding his knees in pain due to chronic inflammation

Key takeaways

  • Inflammation is your body's natural way of protecting itself from anything that could be harmful, such as an infection, an injury, or an irritant.
  • There are two types of inflammation: acute and chronic.
  • Chronic inflammation is harmful to the body and is responsible for some medical conditions, such as rheumatoid arthritis.

Inflammation is an important first line of defense against bodily harm and aims to keep the body in optimal condition, yet it could also be responsible for some chronic diseases such as arthritis and multiple sclerosis.

This article delves into discussing inflammation, its types, causes, and possible treatments.

What is inflammation?

Inflammation is your body's natural way of protecting itself from anything that could be harmful, such as an infection, an injury, or an irritant. 

Inflammation begins with an active immune system recognizing the presence of a threatening foreign body. When a foreign agent, such as a bacterium, enters your body, it triggers the immune system, which initiates an inflammatory reaction to get rid of the foreign agent.

Here are the steps involved in inflammation:

  • Recognition of foreign object: Your body recognizes a foreign object and releases distress chemicals such as histamine and prostaglandin.
  • Increased blood flow: Blood vessels widen to allow for increased blood flow to the affected site. This makes the site red and warm.
  • Swelling: The affected site swells up because the immune cells have arrived to defend the body against harmful microorganisms and begin the healing process.
  • Call for further backup: More immune cells are signaled to come over through the release of proteins known as cytokinesis to quicken the healing process. These cells surround the traitor (for example, a bacterium) to destroy it. Some normal cells and tissues may be damaged in the process.
  • Tissue repair: New body cells and blood vessels replace the damaged tissues and repair them.

Does inflammation cause harm to the body?

Inflammation is necessary for the proper healing of your body but could become harmful when it stays longer than is necessary. This is known as chronic inflammation. Chronic inflammation might occur when:

  • An infectious agent persists in the body.
  • A person is living with an autoimmune disorder.
  • A person is exposed to toxins for a long time.

"Chronic inflammation has also been associated with several autoimmune diseases, with one of the most common conditions being rheumatoid arthritis", said Colin Reily, MD, assistant professor of medicine at the University of Alabama at Birmingham and co-founder of NaturalDos.

Chronic inflammation interferes with the normal healing process, which makes wound healing more difficult. It also limits mobility due to joint pain and impairs organ function.

Signs and Symptoms of Inflammation

Some of the general signs and symptoms of inflammation include:

  • Redness
  • Heat
  • Pain
  • Swelling 
  • Loss of function

Some other bodily symptoms that might not always occur include:

  • Fatigue
  • Fever
  • Joint pain

Types of Inflammation

"There are two types of inflammation, namely acute and chronic inflammation, though all inflammation starts as acute inflammation", explained Keith Burk, MD, founder of KaLaya Health, a leading North American pain relief brand.

Acute inflammation

Acute inflammation is an immediate bodily response to a foreign body and involves the movement of immune cells to the affected site to begin the healing process.

Acute inflammation lasts for a short time—usually a few days. When inflammation lasts for about 2–6 weeks, it is referred to as subacute inflammation, which is an intermediate stage between acute and chronic inflammation.

Chronic inflammation

Chronic inflammation is inflammation that ranges from months to years, with your immune system still producing antibodies even after the infection or injury has been cured.

This long-term response to a non-existent attack on the body eventually becomes dangerous and harms surrounding organs. Diseases caused by chronic inflammation are a leading cause of death worldwide, and their prevalence has consistently increased each year.

Examples of chronic inflammatory diseases include rheumatoid arthritis, diabetes, stroke, and allergies.

Types of chronic inflammation

Chronic inflammation can be classified into two major classes:

  1. Granulomatous chronic inflammation: This type of chronic inflammation occurs due to the formation of granulomas, a group of immune cells such as white blood cells and macrophages. The body continues to attract more immune cells to get rid of the foreign body; when this does not happen, the ball of cells surrounding the unfamiliar object becomes a granuloma. The granulomas could form in response to a chronic infection or a foreign body.
  2. Non-specific proliferative chronic inflammation: This type of chronic inflammation is an immune response characterized by tissue growth due to the abundance of immune cells in the body.

Causes of Inflammation

Things that can trigger or cause inflammation include:

  • Skin cuts: Sharp objects during accidents may result in superficial or deep wounds on any part of the body. Once the skin is cut, the immune system springs into action, seeking to repair the skin. This can lead to an inflammatory response. 
  • Pathogens: This is the most common cause of inflammation, as the body is constantly exposed to harmful microorganisms such as bacteria or viruses. The microorganisms can invade the body from various routes, and once the immune system recognizes their presence, it will initiate an inflammatory response to protect the body from harm.
  • Burns: Burns, which may be due to electricity, chemicals, or heat, can cause mild to severe injuries to the body. The body may initiate an acute inflammatory response in a bid to repair the damaged tissues.
  • Irritants: An irritant is a substance that irritates when in contact with the body. Exposure to irritants such as chemicals and allergens can trigger an inflammatory response. If the exposure to such an irritant becomes prolonged, it might lead to a chronic inflammatory response that persists even when the irritant has been gotten rid of. This is evident in medical conditions like asthma.
  • Autoimmune disorders: An autoimmune disorder is a medical condition in which the immune system mistakenly targets healthy body cells repeatedly. This persistent attack by the immune system induces chronic inflammation and causes damage to multiple organs.
  • Alcohol consumption: Studies have shown that consuming large amounts of alcohol can potentially damage body organs and lead to inflammation of the intestines.

Dr. Burk lists some other possible causes of inflammation, which include:

  • Eating foods that contain trans fat
  • Certain medications
  • Smoking  
  • Chronic stress

Treatment for inflammation

Inflammation can be treated with a combination of medication and lifestyle changes, explained Dr. Reily. Significant compounds used to treat inflammation, such as steroids and non-steroidal drugs, are derived from natural sources.

Medications for treating inflammation

  • Steroids

Steroids are effective in treating inflammation and inflammatory diseases.

Steroids come in various forms, such as tablets, injections, and inhalers, and work by suppressing the genes activated during inflammation. They switch off the genes responsible for mediating inflammation.

While steroids are effective for treating inflammatory conditions, they should only be used under the guidance of a medical doctor. Also, if used for a long time, steroids might lead to possible side effects such as weight gain, sore throats, acne, and mood swings.

  • Non-steroidal anti-inflammatory drugs (NSAIDs)

NSAIDs are either over-the-counter or prescription medications such as ibuprofen and aspirin, which have a wide variety of uses, including treating inflammation.

They work by inhibiting the production of certain enzymes called cyclooxygenases (COX enzymes) that play a role in the inflammatory response, explained Dr. Reily.

Some possible side effects of these drugs may include headaches and indigestion.

Lifestyle changes that may help treat inflammation

Making changes to your lifestyle can greatly help in managing inflammation, especially when used alongside medications. It also promotes your overall well-being.

Dr. Reily discussed some lifestyle changes you can make to help manage inflammation:

  • Eat nutritious meals that are not pro-inflammatory

Making slight changes to your menu can make a huge difference, as a poor diet is a possible trigger for inflammation.

"Consuming foods that contain more proteins and healthy fats, such as avocados, while also reducing your calorie and sugar intake, may help in controlling inflammation", said Dr. Reily.

Fresh fruits and vegetables are also excellent choices, as they are rich in antioxidants, omega-3 fatty acids, and phytochemicals.

  • Maintain a healthy weight

Living a sedentary lifestyle encourages inflammation, which is also linked with weight gain. Maintaining a healthy weight is important for health and fitness, and this can be achieved with a combination of cardiovascular exercises and strength training aimed at improving immune system function.

Dr. Reily explains that aiming for 120–150 minutes of moderate-intensity exercise weekly is a great way to achieve and maintain a healthy weight.

  • Effective stress management

Chronic stress is a major cause of inflammation and underlines the importance of managing stress effectively.

Stress management techniques like deep breathing, meditation, and yoga may help you manage inflammation effectively.

  • Limit alcohol consumption

Excessive alcohol consumption induces inflammation and is a risk factor for other chronic diseases.

Moderate daily consumption of alcohol includes two drinks or less for males and one drink or less for females.

  • Quit Smoking

Extensive research on the link between smoking and inflammation has revealed that smoking suppresses the immune system and activates inflammatory genes.

Secondhand smoking is just as dangerous and increases your risk of chronic diseases. Quitting smoking has a positive effect on the immune system and overall well-being.

When to seek medical attention

It is important to be observant, monitor your health, and seek medical care if you notice any of the following: 

  • Severe pain
  • Inability to perform daily activities
  • Prolonged inflammation
  • Painful swelling

Wrap up

Inflammation is an important body defense mechanism and is crucial to healthy living, yet when prolonged, it can become harmful, which is why it is important to thoroughly understand inflammation and the role it plays in the human body.

By incorporating healthy lifestyle changes and medications, it is possible to manage inflammation effectively. Consulting your physician is important for making healthy decisions.


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