Oz, the eldest child of popular television doctor Mehmet Oz and Lisa Oz (née Lemole), was born in Philadelphia, Pennsylvania. She was born with the umbilical cord wrapped around her neck and was given an Apgar score of 2, but made a full recovery. Her paternal grandparents, Suna (née Atabay) and Mustafa Öz, emigrated from Konya Province, Turkey. She also has Shapsug (Circassian) ancestry from her maternal great-grandparents. She was raised in Cliffside Park, New Jersey, where she graduated from Dwight-Englewood School in 2004. She has three siblings, Arabella, Zoe and Oliver. Oz graduated with a degree in Near Eastern Studies from Princeton University in 2008.

In 2007, she published The Dorm Room Diet Planner (Newmarket Press, 2007). In 2012, she collaborated with the rest of the cast of The Chew to author The Chew: Food. Life. Fun. Oz also is the author of the New York Times bestselling Relish: An Adventure in Food, Style, and Everyday Fun. The book contains recipes, tips, relationship and career advice, and the author’s personal anecdotes. Oz has written articles for Glamour and The Huffington Post. In 2012, she wrote five articles for a column called “Food for Thought” for Creators Syndicate.

Oz speaks publicly on lifestyle and health topics. In 2008, she was invited to speak at The Governor’s Women’s Conference, hosted by Maria Shriver. Oz was a featured speaker at The Aspen Institute’s 2009 Aspen Health Forum. In 2011, Oz and her mother Lisa were the featured speakers at WCBS Radio’s Working Women’s Luncheon. Daphne Oz has delivered addresses to campus audiences including Princeton University, University of Pennsylvania, Brown University, and Georgetown University.

On August 26, 2010, Oz married John Jovanovic at the Municipal Marriage Bureau in Manhattan. Jovanovic is an investment fund analyst, whom Oz met at college. The civil ceremony was followed by two religious ceremonies on August 28, 2010. A morning ceremony was held at the Synaxis of Serbian Saints Church in Portland, Maine. A second ceremony was held in the evening at the summer home of Oz’s maternal grandparents, Gerald and Emily Jane Lemole, in Cumberland Foreside, Maine. The ceremony was led by the Rev. Prescott Rogers of the Swedenborgian Church.

Oz was one of five co-hosts on ABC’s The Chew, a weekday one-hour lifestyle show, which premiered in September 2011. On August 11, 2017, it was confirmed that Oz would be leaving the show prior to the release of the seventh and final season. Oz has been featured as a guest co-host on The View, Beat Bobby Flay, and has appeared as a healthy living expert on Good Morning America, Fox & Friends, The Dr. Oz Show, The Rachael Ray Show, Dayside, and Good Day New York. She was also one of the celebrity guests on the game-show Celebrity Name Game. Oz is currently a judge on the Food Network competition show Cooks vs. Cons. On July 17, 2019, it was announced that Oz would be joining Gordon Ramsay and Aarón Sanchez on the eighth season of MasterChef Junior, replacing previous judge Christina Tosi.

On February 26, 2014, Oz gave birth to a daughter named Philomena “Philo” Bijou Jovanovic. Her father described the baby as being a blue-eyed Circassian beauty like her mother. Daphne gave birth to a son, Jovan Jr. (nicknamed “John-John”) on October 21, 2015. On June 6, 2017, Oz announced on The Chew that she was expecting her third child the following winter. On December 4, 2017, Oz gave birth to a daughter, Domenica Celine Jovanovic. On August 14, 2019, Oz gave birth to her fourth child, daughter Giovanna “Gigi” Ines Jovanovic.