First of all give the answer of the following questions:
- Why I will boost my immune system?
- How good is my system now?
- What are my risks?
After that, make a plan how You will start. And I recommend to You, if it´s affordable: ask Your Doctor, to do some laboratory examinations for You. You have to know, that we don´t have any reliable laboratory parameter that can mesure the state of Your immune system. But thera are some indicators, which can help You:
Vitamin D, Vitamin B6, Vitamin B12, zinc, selenium, folic acid.
This are some very useful parameter, who helps out to find out in which condition Your immune system is. They define Your actual status. Later, You can do it again (maybe in 6 months) to compare with the new ones.
A medical check up with physical examination and some ultrasound examination would also be necessary, so You can find out, if Your health is in a good state.