diff --git a/dune/gfe/polardecomposition.hh b/dune/gfe/polardecomposition.hh
index 6f3ecb862113d5e241bc267d0bdd701ec3e43406..9f7098aeae2dfaa01cd30e81ad3887ca558ab7aa 100644
--- a/dune/gfe/polardecomposition.hh
+++ b/dune/gfe/polardecomposition.hh
@@ -25,7 +25,7 @@ namespace Dune::GFE {
         template <class field_type>
         FieldMatrix<field_type,3,3> operator() (const FieldMatrix<field_type,3,3>& matrix, double tol = 0.001) const
         {
-            int maxIterations = 100;
+            size_t maxIterations = 100;
             // Use Higham's method
             auto polar = matrix;
             for (size_t i=0; i<maxIterations; i++)
@@ -323,4 +323,4 @@ namespace Dune::GFE {
     };
 }
 
-#endif
\ No newline at end of file
+#endif