Younan Nowzaradan (born October 11, 1944), also known as Dr. Now, is an Iranian-born Assyrian-American doctor, TV personality, and author. He specializes in vascular surgery and bariatric surgery. He is regarded ​as one of the most experienced and ​knowledgeable weight loss ​physicians. He works with obese, ​morbidly obese, and often super-​obese individuals, bringing innovative ​solutions to weight loss and surgical ​interventions.

He has ​pioneered surgical ​techniques to accommodate ​super-morbidly obese ​patients, significantly ​advancing the field of ​bariatric surgery. He is a leader in laparoscopic surgical techniques, including pioneering laparoscopic appendectomies and cholecystectomies. 

He is known for helping morbidly obese people lose weight on My 600-lb Life (2012–present) and The 6000 lb Diaries with Dr. Now (2025).