The body will not lie. There are several common manifestations of people with low immunity!

By: HSEclub NewsJul 25, 2025

A person who is usually strong and rarely catches a cold suddenly starts to get sick repeatedly. He has two lung infections in just two months. The symptoms are more severe each time, and he even needs to be hospitalized for infusion treatment.

This is not accidental, nor is it "normal for old age", but the body is sending a signal: there is something wrong with the immune system.



Many people regard immunity as a vague word, thinking that it is just "lack of nutrition" or "not drinking enough hot water", but the immune system is a whole set of complex defense networks. It works silently every day to help us resist thousands of viruses and bacteria from the outside world, as well as cells in the body that may go bad. Once it has problems, the consequences are more than just "easy to catch a cold".

The decline in immunity will not be silent, the body will quietly give some "warning signals". It's just that most people don't take these signals to heart.

Today, let's talk about the five symptoms that people with low immunity often have. You can check to see if you have been affected.



Many people have experienced repeated oral ulcers, especially after changing seasons, staying up late, and being under great pressure, their mouths suddenly "break".

Some people break several places at a time, and the pain makes it difficult to eat or talk. There is a "self-protection mechanism" in the mouth. Under normal circumstances, these microorganisms are balanced. Once the immunity decreases, harmful bacteria will take advantage of the situation, causing damage to the oral mucosa and repeated ulcers.


One or two oral ulcers are no big deal, but if they recur, recover slowly, and cover a large area, you must be alert to whether there is a problem with the immune system. Doctors often recommend a blood routine and immune function test to rule out systemic diseases, such as leukopenia or other basic problems.



Let's talk about another symptom that many people ignore - chronic diarrhea. Some people's stomachs are always restless. They have diarrhea when they eat something cold, and they "go to the toilet" when they change their taste. This "intestinal sensitivity" may be related to intestinal immune disorders.

The intestine is not a simple "digestive tract", it is one of the largest immune organs in the human body. The intestinal flora is like an ecosystem, and healthy flora can help us resist foreign bacteria. But if the immunity is poor and the number of harmful bacteria increases, it is easy to cause an imbalance of intestinal flora, resulting in frequent diarrhea, bloating, and even constipation.

If you find that you eat normally and eat regularly, but you always have diarrhea, accompanied by fatigue and weight loss, then you must pay attention to it.



Lung problems should not be ignored. Many people think that coughs and colds are minor problems, but if you find that you catch a cold three or four times a year, and each time it takes a long time, or even develops into pneumonia or bronchitis, then you must be alert to whether the immune system is "falling off the chain".

The lungs are in contact with the outside air every day. There are various viruses, bacteria, and fungi in the air. When the immunity is normal, the body can keep these "enemies" out of the door. But once the immunity decreases, it's like there is no security guard at the door, and bacteria can easily "break in" and cause lung infection.


Especially for some middle-aged and elderly people who suffer from hypertension, diabetes, and chronic obstructive pulmonary disease, it is more likely to cause repeated infections due to low immunity. At this time, if you just use antibiotics repeatedly without solving the problem of immune basis, it will only make the treatment worse.

Let's talk about another common but easily misunderstood manifestation: swollen tonsils or lymph nodes. Many people had tonsillitis when they were young and thought it was a trivial matter. But if adults often have swollen lymph nodes in the neck, armpits, and groin, especially accompanied by fever, night sweats, and weight loss, then you have to be vigilant.


Tonsils and lymph nodes are originally part of the immune defense line, like outposts. Once foreign enemies invade, they will "fight" and swell. But if it is repeated swelling, or the lump is not painful and persists, it may be an immune abnormality or even a precursor to lymphatic system diseases.

Some patients went to the hospital for a check-up because they felt that "there was a lump on their neck", and it turned out to be an early lymphoma. Don't wait until the symptoms are serious to regret it. Every abnormality in the body actually has a reason.


The last signal, which seems to be the most "ordinary" but is the easiest to be ignored, is always tired and lack of energy. Many people think that they are tired because they are old, busy with work or have poor sleep. Continuous fatigue is often the first signal of decreased immunity.



The immune system not only protects us from illness, but also participates in regulating the body's energy distribution. If the immune system "alarms", the body will automatically "run at a lower frequency", and at this time you will feel particularly sleepy, lack of energy, and lack of energy to do anything.

Sometimes, just "sleeping more and making up for sleep" alone cannot solve the problem. Instead, we need to start from diet, exercise, work and rest, etc. to improve the body's overall immune level.


In the final analysis, immunity is not a false concept, it is a real force that affects every corner of our body. From the mouth to the intestines, from the lungs to the lymph, from the mental state to the quality of life, it is like a "steward" behind the scenes, silently determining our health ups and downs.

Once this "steward" strikes, the body will tell you in various ways: I can't hold on.


Don't take those "minor problems" lightly. Repeated oral ulcers, frequent diarrhea, lung infection, swollen lymph nodes, constant fatigue and weakness, these seemingly scattered signals may have a common root behind them: immunity is declining.

Pay more attention to a balanced diet, maintain a good work and rest schedule, exercise moderately, stay up late less, and have less stress, which is the best protection for the immune system. If necessary, go to the hospital for an immune function test, don't wait until the body "complains" before thinking of conditioning.

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Related Tags
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