Consuming foods high in sugars, saturated or trans fats, and processed meats can contribute to inflammation. In contrast, choosing an anti-inflammatory diet abundant in fruits, vegetables, fish, whole grains, nuts, and olive oil can reduce inflammation and lower the risk of chronic diseases.

When the body gets injured, it usually reacts with inflammation, which causes redness, warmth, swelling, and pain in nearby tissues and joints. This happens because the immune system sends white blood cells to the injured area. Most people are familiar with this kind of inflammation, known as acute inflammation.

Nevertheless, there are instances when inflammation persists for several months to years, even in the absence of a foreign invader posing a threat. This is also referred to as acute inflammation or slow or long-lasting inflammation. Many major illnesses such as cancer, diabetes, heart disease, Alzheimer’s, depression, and arthritis are associated with chronic inflammation.¹

What causes inflammation?

The most common causes of chronic inflammation include:

• Autoimmune disorders, like lupus, where your body mistakenly attacks healthy cells
• Exposure to toxins, such as air pollutants or industrial chemicals
• Untreated acute inflammation stemming from an infection or injury
• Autoinflammatory disorders, like recurrent fever syndromes, where the cells in charge of halting inflammation are defective
• Repeated occurrence of acute inflammation

Some Lifestyle factors such as:

• Drinking alcohol in excess
• Having a high body mass index (BMI)
• Intense exercise or physical inactivity
• Experiencing chronic stress
• Smoking
• Certain foods

Persistently choosing the wrong foods can accelerate the inflammatory disease process.

Foods that cause inflammation

Refined carbohydrates

In this category fall foods and drinks such as white bread, pasta, cakes, sweets, sodas and other sugary drinks.

Carbohydrates can be categorised into two main types based on their chemical structure: simple and complex. Simple carbohydrates consist of only one or two sugar units, while complex carbohydrates comprise numerous sugar units. Among simple carbohydrates, we encounter monosaccharides, single sugars such as glucose, fructose, and galactose, and disaccharides formed from two sugars like maltose, sucrose, and lactose. Complex carbohydrates, on the other hand, are made of a higher number of sugar molecules.²

Simple Carbohydrates are quickly utilised for energy, causing a spike in blood sugar and insulin secretion from the pancreas. In contrast, complex carbohydrates are those consisting of three or more sugars bonded together in a more complex chemical structure. The latter needs additional time to digest, leading to a slower increase in blood sugar levels.

Research suggests that excessive sugar consumption has been linked to problems with metabolism, increased inflammatory substances in the body, and the activation of specific pro-inflammatory cytokines in various tissues. All these factors can lead to insulin resistance, a condition where cells do not respond well to insulin, and persistent low-grade chronic inflammation.³

Fried foods

Research shows that consuming fried foods not only triggers inflammation in the intestine but also worsens existing inflammation and increases gut permeability in both animal models and humans. It's believed that high-fat foods can cause flare-ups in patients with Inflammatory Bowel Disease (IBD), a chronic inflammatory condition of the digestive tract. Consequently, a significant reason why diets designed for IBD often focus on significantly reducing or eliminating fats.⁴

Red meat and processed meat

In a study involving 403,886 participants (aged 38–73 years) from the UK Biobank, it was found that higher consumption of meat, particularly processed meat, among British adults was associated with elevated levels of inflammatory markers in the body. However, researchers of this study reported that the link between eating more meat, especially processed meat, and inflammation is not strong, and the main reason for this connection seems to be that those individuals have higher levels of body fat.⁵

Foods high in trans fats 

Studies have shown that consuming foods high in saturated or trans fats, such as margarine, shortening and lard, triggers inflammation and increases body weight, insulin resistance and risk of heart disease.^6,7

Who might benefit from an anti-inflammatory diet?

Individuals with a chronic health condition are likely also facing chronic inflammation. Conditions linked with inflammation include

• Crohn’s disease
• Heart disease
• Irritable bowel syndrome
• High blood pressure
• Obesity
• Type 1 diabetes
• Multiple sclerosis
• Ulcerative colitis
• Psoriasis
• Rheumatoid arthritis

Diets shown to reduce inflammation

Mediterranean diet

People who live in countries surrounding the Mediterranean Sea, like Greece and Italy, have routinely followed a diet consisting mainly of fruits and vegetables, seeds and nuts, fish, whole grains, and olive oil — foods that are typically endorsed by experts for their anti-inflammatory properties. Over time, studies have revealed that people who adhere to this diet have lower rates of disease and live longer than people in the United States who eat a Western-style diet.

Experts consider the Mediterranean diet to be one of the most beneficial diets and for valid reasons. Studies demonstrate its ability to protect against diseases linked to inflammation, such as cardiovascular disease, metabolic syndrome, and type 2 diabetes, and because it includes a variety of foods, the Mediterranean diet is relatively easy to adopt and maintain.

DASH diet

DASH stands for Dietary Approaches to Stop Hypertension. This diet was initially created to lower blood pressure without medication but is now widely considered one of the healthiest dietary regimens. It contains foods low in total fat, saturated fat, and cholesterol while abundant in fruits, vegetables, and whole grains. Low-fat dairy, fish, poultry, and nuts provide protein. Red meat, sugary drinks and sweets are restricted in this diet. DASH is abundant in fibre, potassium, calcium, and magnesium and low in sodium.

Can vegetarianism reduce inflammation?

Though meat can increase inflammation, avoiding animal products doesn’t automatically mean eating healthier.

Choosing to be vegetarian, pescatarian or even vegan can still involve consuming foods like potato chips, fries and sweets. For those seeking anti-inflammatory benefits, choosing whole, unprocessed foods with no added sugars is essential.

Anti-inflammatory foods and beverages

An anti-inflammatory diet should contain the following foods and beverages:

• Olive oil
• Green leafy vegetables, such as kale, spinach and collards
• Tomatoes
• Nuts like walnuts and almonds
• Fish rich in healthy fats, like salmon, anchovies, tuna, mackerel, and sardines
• Fruits such as blueberries, strawberries, cherries, apples, and oranges
• Coffee

In addition to reducing inflammation, a less processed diet can benefit your physical and emotional health. A healthy diet has positive effects by lowering the risk of chronic diseases and boosting mood and overall quality of life.

How can inflammation be prevented?

You may reduce your chronic inflammation risk by adopting healthier lifestyle habits. Some of these habits include:

• Maintaining a healthy weight
• Avoiding or quitting smoking
• Limiting your alcohol intake
• Exercise regularly
• Managing your stress levels

Summary

Inflammation, a natural response to injury, can become chronic and is linked to major illnesses like cancer, diabetes, and heart disease. Certain foods such as refined carbohydrates, red and processed meats, and those high in trans fats have contributed to inflammation and the risk of diseases. Diets such as the Mediterranean and DASH diets, which are rich in whole foods, effectively reduce inflammation and prevent related diseases.

Vegetarianism can also reduce inflammation if it focuses on whole, unprocessed foods. Anti-inflammatory foods, including olive oil, leafy greens, nuts, and fatty fish, can alleviate inflammation and reduce the risk of chronic diseases. Additionally, a less processed diet can positively affect emotional well-being.