What Kind of Doctor Do I Need? Slideshow Dental (Oral) Health Quiz Causes of a Heart Attack Slideshow FEV1: Forced Expiratory Volume in the first second. The volume of air that can be forced out in one second after taking a deep breath, an important measure of pulmonary function. From Healthy Resources When Prostate Cancer SpreadsDo You Take Good Care of Your Eyes?Tips for a Clean Home & Healthy Cat Featured Centers When Prostate Cancer SpreadsEssential Tips to Manage DiabetesWhat Is Cystic Fibrosis? What Causes It? Health Solutions From Our Sponsors Kept Your Wisdom Teeth? Therapy at Home?