Cook's leadership of the Test side has been questioned again, as it was in the aftermath of the 5-0 Ashes whitewash to Australia in the winter, following a first ever home series defeat to Sri Lanka last month.
The left-handed opener has also struggled with the bat during the past 12 months, averaging only 25 in a year in which he has failed to reach three figures, but is determined that he will not step down.
Broad is familiar with the pressures of captaincy as skipper of England's Twenty20 team and sympathises with Cook's position, but is sure that one major innings will relieve pressure on the 29-year-old.
"He's a relaxed guy. I mean there's a few of us who have played long enough to know that we're in a stats driven business and a results driven business," Broad told reporters.
"When you're not scoring your runs or taking your wickets you expect a certain amount of flak and that won't change until he scores a hundred, and Cooky knows that.
"Obviously winning helps. Winning Test matches will help with his captaincy, but even if we are winning and he's not scoring hundreds, he'll still be getting a certain amount of stick. He's very honest, he's very open, he knows he's a score away."
England's next Test is the first in a five-match series against India, which begins at Trent Bridge on July 9.