Does an “anti-inflammatory diet” really work? Are foods that claim to be “anti-inflammatory” just a waste of money?

The May Day holiday is over. Many people enjoyed various delicious foods during this long holiday, but when they returned to reality, they found that their bodies were not able to adapt.

Image source: gifer

Some people may feel hot and dry in the mouth; some may feel bloating, stomach pain, and indigestion. These discomforts are usually related to diet, and one of the important factors is the increase in inflammatory response in the body. So, let's talk about "anti-inflammatory diet" today and see how to reduce inflammatory response through diet and restore the body to a healthy state.

Regarding the "anti-inflammatory diet", some people say that if you don't pay attention to anti-inflammatory, you may suffer from many diseases; some people say that certain foods are better at anti-inflammatory effects than other foods; and some people recommend dietary supplements.

Related discussion, image source: Weibo

Are these statements right or wrong? To understand this question, we need to first understand chronic inflammation.

What is chronic inflammation?

Inflammation is an emergency response mechanism of the human body; chronic inflammation can be seen as a false warning.

We can use an everyday analogy: every summer, coastal cities are hit by typhoons. To deal with such disasters, the government will issue typhoon warnings and notify everyone through television and mobile phones; it will also try to reduce losses, such as suspending buses and subways and urging citizens to stay indoors; it will also mobilize manpower to carry out repairs immediately in the event of emergencies such as power failures.

When the immune system detects pathogenic microorganisms, it will also carry out emergency management. For example, pneumonia can cause fever, and conjunctivitis can cause red and swollen eyes, reminding us to pay attention to our own condition; for example, the decline in vitality makes us less interested in exercise and always want to lie in bed in order to save energy and focus on fighting the infection; for example, the state of local tissues is changed to mobilize as many immune cells as possible to kill invading microorganisms.

Therefore, normally, inflammation has a clear cause, develops very quickly, and can cause significant discomfort. However, in recent years, scientists have discovered a special type of inflammation - systemic chronic inflammation . This type of inflammation is the opposite of normal: it has no clear cause, lasts for a long time, and may even last a lifetime, and patients often don't know they have inflammation.

Is chronic inflammation the root cause of all diseases?

Chronic inflammation is indeed associated with many diseases.

According to the cause, diseases can be divided into two categories: one category, like pneumonia and conjunctivitis mentioned above, is related to microbial infection; the other category is not related to infection and is called non-infectious diseases, also called chronic diseases.

Chronic diseases are the leading cause of death in humans

Image source: World Health Organization

In recent years, there have been many popular science articles about microorganisms. Many readers may be surprised that there are so many dangerous organisms hidden in places invisible to the naked eye. In fact, there are also many types of chronic diseases, such as cardiovascular disease, cancer, diabetes, arthritis, autoimmune diseases, etc.

Their impact is wide and everyone may encounter them; if not treated in time, it may affect life expectancy. Therefore, scientists have been hoping to understand the detailed mechanisms of these diseases. During the research process, they found that patients all had systemic chronic inflammation in their bodies.

Consequences of chronic inflammation, Image source: Author's own

Let's imagine: what would happen if a city issued a wrong typhoon signal? The answer is obvious, industrial production and people's lives would be affected. Similarly, systemic chronic inflammation may affect human metabolism and even damage cells, leading to various chronic diseases.

Is there any way to check for chronic inflammation?

There is currently no accurate and convenient way to check this.

Inflammatory reactions produce some special substances, such as C-reactive protein. Studies have shown that systemic chronic inflammation can cause elevated C-reactive protein. However, this protein is synthesized by the liver and is sensitive to bacteria, fungi, and parasites. It is also related to tumors and tissue necrosis. In other words, elevated C-reactive protein may not be a sign of systemic chronic inflammation.

Other inflammatory markers have similar problems. Therefore, there is no unified solution for how to detect systemic chronic inflammation. However, systemic chronic inflammation is an abnormal state after all. If it exists for a long time, it may cause some less obvious symptoms , such as repeated infections and constant fatigue.

Symptoms of chronic inflammation, Image source: self-made by the author

How to get rid of chronic inflammation?

Scientists have not yet figured out the source of systemic chronic inflammation, but have identified some risk factors that, if present, increase the likelihood of experiencing systemic chronic inflammation.

Fortunately, most of the risk factors are related to lifestyle , and we have talked about them many times, such as controlling weight, paying attention to diet, and maintaining a regular schedule.

What is related to chronic inflammation?

Image source: Made by the author

In addition, we should remind everyone that health is a systematic project, not a simple addition and subtraction. For example, energy intake is a risk factor for systemic chronic inflammation, but who can avoid eating? For another example, alcohol can slightly reduce the inflammatory state, but considering the pros and cons, it is better not to overdo it.

What should we pay attention to when eating?

It's also a cliché.

Anti-inflammatory diet, Image source: Made by the author

In 2009, scholars found that there is a correlation between food ingredients and the inflammatory state of the human body . For example, beta-carotene and caffeine can reduce inflammation. As a result, a dietary plan aimed at reducing or minimizing systemic chronic inflammation was proposed, namely, an anti-inflammatory diet.

So, will everything be fine if we just eat more anti-inflammatory foods?

Of course not.

Daily diets have complex ingredients, and we need to pay attention to the quantitative relationship of each ingredient . β-carotene can fight inflammation, but a large pot of red meat stewed with carrots will have the opposite effect; caffeine can certainly reduce inflammation, but according to the advice of scholars, adults only need to consume 210~400mg of caffeine per day. Furthermore, the cooking method will affect the composition of food. For example, high-temperature cooking of meat will produce heterocyclic amines, polycyclic aromatic hydrocarbons, and glycation end products, all of which will promote inflammation.

Conclusion

Systemic chronic inflammation may sound new, but the solutions to it are not new. As long as you live a healthy life, there is nothing to worry about.

References:

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[5] PAHWA R, GOYAL A, JIALAL I. Chronic Inflammation[M/OL]//StatPearls. Treasure Island (FL): StatPearls Publishing, 2023[2023-04-27]. http://www.ncbi.nlm.nih.gov/books/NBK493173/.

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Zhao Yanchang Popular Science Author