Ftera smoker quits how long does it tke for oxygen level to return to normal?

When a smoker quits, their oxygen levels begin to improve within hours, with significant changes occurring after about 12 hours as carbon monoxide levels in the blood decrease. By 2 to 12 weeks after quitting, lung function and circulation improve, leading to better oxygen delivery throughout the body. Typically, it may take several weeks to months for oxygen levels to stabilize and approach those of a non-smoker, depending on the individual's health and smoking history.