What are the effective ways to improve immune function?

For improving immune function, there are many products on the market, but many are just verbal claims, and it is hard to find any backed by experimental data. It is suggested that units with the means should do some work in this area, especially research departments funded by the state.
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The microecological effect is still pretty good, but it is best to use imported ones. The quality is more stable.
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Does the microecology the friend above mentioned refer to probiotics?
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There are also many good domestic ones
Imported is not necessarily good
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Could you give a few examples?????
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Wow! Even probiotics can boost immunity, not bad, seems to make some sense, then vitamins, minerals, amino acids.... can all boost immunity too.
I think the key points are balanced nutrition, good management practices, and biological control - these are the ways to boost immunity!
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Health is the prerequisite!
What the person above is talking about is intestinal mucosal immunity!
But there are many more components in the immune system!
1. Lymph 2. Liver 3. Kidney 4. Spleen 5. Mucosa of various passages 6. Thymus 7. Lung 8. Hair, etc.!
A good microecological product can indeed produce an intestinal mucosal immune effect (look at the vitality of the bacteria, not the bacterial count)
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Profound theory!!!! Learn, learn!! Many things are easier said than done
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Right, look at the vitality of the bacteria, not the bacterial count.....................................
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For microecological preparations, this is indeed a key indicator
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I do not know much, I have learned something.
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In academic matters, it is precisely by letting a hundred schools of thought contend that things get better