I'm healthy but don't exercise much, i'm 21. i don't have diabetes/major problems. could you need an amputation for not exercising? i exercise now.

Just do it: Your young start exercising routinely and hopefully stay healthy.

Don't smoke: Pvd risks including diabetes (due most commonly from obesity), hypertension, hyperlipidemia ( high serum cholesterol), and tobacco. The worst offender/promoter of vascular disease in general is tobacco. Eat a mediterranean diet, avoid tobacco, & remain lean & you'll avoid complications of vascular disease.