I see I got downvoted. This is well established and not controversial at all. Lots of research supports it.

From https://pmc.ncbi.nlm.nih.gov/articles/PMC4791086/

> There is strong evidence indicating that excess adiposity negatively impacts immune function and host defence in obese individuals.

Adipose tissue is body fat.

More references:

- https://www.sciencedirect.com/science/article/pii/S216183132...

- https://www.mdpi.com/2075-1729/14/7/856

- https://pmc.ncbi.nlm.nih.gov/articles/PMC296995/

I suggest discussing it with your favorite AI if you doubt it ¯\_(ツ)_/¯