homeless people in SF dropped dead in greater numbers from drug overdoses than COVID-19
I think homeless people likely have pretty good immune systems from living outside in the fresh air so much—not sure what being addicted to drugs does to the immune system, however.
And the homeless in SF (I work in Civic Center/Tenderloin so have seen them daily for decades, until covid) are not obese. They also get a lot of Vitamin D from living in the CA sun.