Let's do the math
a) Let's assume we live to be 100 years old
b) The study took 26 years
c) They claim "a 20% higher chance of death during the study"
d) Each year brings us one year closer to death, 1 year = 1 percent of 100 years.
So, in 26 years the chance of dying should increase by 26 percent. But according to the study it only increases by 20 percent. Hooray, eating red meat makes You live longer.