The nurse is correct , perhaps more than she knows:
https://www.webmd.com/diet/health-benefits-black-pepper#:~:text=When%20you%20add%20black%20pepper,nutrients%20absorbed%20into%20your%20bloodstream.&text=Black%20pepper%20helps%20to%20stimulate,absorb%20the%20foods%20you%20eat.
While I support use of holistics,I must warn that many of them are not water soluable and thus may accumulate in the body and possibly become toxic. Thus knowledge and care must be taken, Having said that here are some you might look at:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6464502/#:~:text=Selenium%20acts%20against%20cell%20damage,frequently%20used%20by%20cancer%20patients.
https://www.mdanderson.org/newsroom/study-finds-vitamin-e-can-boost-immunotherapy-responses.h00-159538956.html
Vitamin A perhaps needs close monitoring because of posible toxicity:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8465379/
Intravenous Vitamin C is in trials to be used with chemotherapy with the benefits many would like, but it is not approved by the FDA.

I should add that many hospitals are opposed to holistic because of unknown quality, dosing information and need for legal policy. Some won't allow holistic. The same is true of doctors. Many are afraid of losing their licence to practice if they suggest holistics. Currently, I believe it is best for individuals to take more responsibility for their nutrition and health. Information is more available today than ever.