Chestnut, 35, of San Jose, Calif., won his 12th title by consuming 71 hot dogs in 10 minutes, defeating 17 opponents. He has consumed at least least 70 hot dogs the past three years: 74 in 2018, 72 in 2017 and 70 in 2016.
Sudo, 34, of Las Vegas, won her sixth title in a row in the women's competition, consuming 31 dogs. Last year she ate 37.
Chestnut finished 21 hot dogs ahead of Darron Breeden, 30, of Orange, Va., in second with 50. Last year Breedon ate 43 hot dogs to finish in third place.
This year, Geoffrey Esper, 44, of Oxford Mass., finished in third with 46.
Matt "The Megatoad" Stonie, 27, who ended Chestnut's eight-year winning streak four years ago finished fourth with 46.
Carmen Cincotti, 26, of Mays Landings, N.J., finished second last year with 63 but did not compete this year.
Chestnut started strong, consuming 10 hot dogs per minute, and jumping out to a 10-dog lead after a few minutes.
"It was just going for 75," Chestnut said Thursday on the broadcast. "I always like a new record. Everyone was here wanting a new record, standing in the heat. Next year I'll figure how to do it."
Chestnut totals in minute increments were: 10, 20, 30, 38, 45, 51, 56, 62, 66 and 71.
"I came out fast and slowed down faster than I'd like," Chestnut said. "Tried to adjust and chew more. But I was slowing down. I don't know if it was the heat or what."
In 2007, Chestnut dethroned Takeru Kobayashi, from Japan, who won six titles in a row.
In 2001, Kobayashi ate 50 hot dogs and buns -- doubling the previous record. He hasn't competed since 2009 due to a refusal to sign an exclusive deal with Major League Eating.
Sudo was six behind her effort last year of 37 but has won six of the nine competitions since a separate women's division was created in 2011.
Despite the smaller number, she easily beat runner-up Michelle Lesco, 34, of Tucson, Ariz., who finished second with 27. Juliet Lee, 54, of Germantown, Md., and Sarah Reinecke, 32, of Seattle, tied for third with 23.
Sonja "The Black Widow" Thomas, 51, of Alexandria, Va., owns the record with 45 but was not in the field of 15 women.
In 1916, Polish immigrant Nathan Handwerker opened a nickel hot dog stand on Coney Island with a $300 loan from two friends. It's still there at Surf and Stillwell.