The supersized NFL behemoths who have dined on steak and milkshakes and clogged up the field for about a century are suddenly doing the unthinkable: they're on a diet.

Baltimore Ravens linebacker Ray Lewis told reporters he's lost far more than 20 pounds this year with more to come. His Ravens teammate, linebacker Jameel McClain, is also shedding bulk. Washington Redskins linebacker Lorenzo Alexander has proclaimed that he's already dropped about 30 pounds.

It's...