Mark Sisson (born July 20, 1953) is an American fitness author, food blogger, and a former distance runner, triathlete and Ironman competitor.^[1]

Sisson was born in Maine and is the oldest of four siblings. He attended Williams College, where he was a pre-med candidate and earned a biology degree.^[2]

Sisson finished 4th in the February 1982 Ironman World Championship.^[3] In the 1970s, he was a record-setting runner for the Portland (Maine) Track Club.^[4] He had a top-5 finish in the 1980 U.S. National Marathon Championships and earned a qualifying spot for the 1980 U.S. Olympic Trials.^[2]

He is a follower of the paleo diet^[5] and markets his own version of it, called the "Primal Blueprint" diet.^[6] As part of this initiative, he started a food blog, "Mark's Daily Apple," in 2006 and has also written a number of diet and exercise books;^[7]

Sisson served for 15 years as chairman of the International Triathlon Union (ITU) Anti-Doping Commission and as the ITU's liaison to the International Olympic Committee.^[3]

In 2015, Sisson and Morgan Buehler co-founded Primal Kitchen, "an authentic, premium and growing brand that ... offer[s] health-conscious consumers the best possible choices in Condiments, Sauces, Dressings and Healthy Snacks." In 2018, Kraft Heinz announced a definitive agreement to acquire Primal Kitchen for approximately $200 million.^[8]

In 2021, Sisson and his son, Kyle Sisson co-founded Peluva, a barefoot shoe brand.^[9]

• The Primal Blueprint (2009, ISBN 978-0982207703)
• The Primal Connection (2013, ISBN 978-0984755103)
• The New Primal Blueprint (2016, ISBN 978-1939563309)
• The Keto Reset Diet (2017, ISBN 978-1524762230)
• Primal Endurance (2015, ISBN 978-1939563088)
• Two Meals a Day (2021, ISBN 978-1538736951)
• Born to Walk (2025, ISBN 978-1736294413)

• Mark Sisson at IMDb
• Mark's Daily Apple
• Mark Sisson's Untethered