There are many reasons for people to be sickly. Genetics, poor choices as teens, diabetes, smoking, drugs, obesity, poor nutrition.
All are risks to good health. Some people can get away with these bad habits more than others d/t genetics.
If you know what is good for you and you still choose to make poor choices, you have reason to worry.
You are a nurse, educated and know better, so don't worry. Now go for a long stress reducing walk!!!!