1 of 8 MariaCallas1951191502–768×949.jpg [https://nypost.com/wp-content/uploads/sites/2/2013/08/mariacallas1951191502-768x949.jpg?quality=90&strip=all&w=477] BEFORE: Maria Callas was a legendary soprano. ASSOCIATED PRESS 2 of 8 50702933191508–768×949.jpg [https://nypost.com/wp-content/uploads/sites/2/2013/08/50702933191508-768x949.jpg?quality=90&strip=all&w=477] AFTER: When Callas lost 100 pounds, her voice changed. Time & Life Pictures/Getty Images 3 of 8 SopranosReturn191451–768×949.jpg [https://nypost.com/wp-content/uploads/sites/2/2013/08/sopranosreturn191451-768x949.jpg?quality=90&strip=all&w=477] BEFORE: The Royal Opera House fired a too-large Deborah Voigt. AP 4 of 8 OperaGotterdammerung191514–768×949.jpg [https://nypost.com/wp-content/uploads/sites/2/2013/08/operagotterdammerung191514-768x949.jpg?quality=90&strip=all&w=477] AFTER: Voigt slimmed down with gastric bypass. AP 5 of 8 13E.stan.C.TA_114–768×949.jpg [https://nypost.com/wp-content/uploads/sites/2/2013/08/13e-stan_-c-ta_114-768x949.jpg?quality=90&strip=all&w=475] BEFORE: Harlem-based baritone Stan Lacy weighed 245 pounds. Beowulf Sheehan 6 of 8 120312OperaZM30191527–768×949.jpg [https://nypost.com/wp-content/uploads/sites/2/2013/08/120312operazm30191527-768x949.jpg?quality=90&strip=all&w=477] AFTER: Lacy dropped to 185 pounds with a crash diet. Zandy Mangold 7 of 8 FinalHRPIC3195042–768×949.jpg [https://nypost.com/wp-content/uploads/sites/2/2013/08/finalhrpic3195042-768x949.jpg?quality=90&strip=all&w=477] BEFORE: Michael Fabiano was a flabby tenor. 8 of 8 UActIII191526–768×949.jpg [https://nypost.com/wp-content/uploads/sites/2/2013/08/uactiii191526-768x949.jpg?quality=90&strip=all&w=477] AFTER: Now thanks to exercise, Fabiano is happy to bare his skin onstage. Cory Weaver