diff --git a/gtsam/linear/JacobianFactor.cpp b/gtsam/linear/JacobianFactor.cpp
index 4597759e3..56a5dc085 100644
--- a/gtsam/linear/JacobianFactor.cpp
+++ b/gtsam/linear/JacobianFactor.cpp
@@ -188,7 +188,7 @@ boost::tuple<FastVector<DenseIndex>, DenseIndex, DenseIndex> _countDims(
     m += factor->rows();
   }
 
-#ifdef GTSAM_EXTRA_CONSISTENCY_CHECKS
+#if !defined(NDEBUG) && defined(GTSAM_EXTRA_CONSISTENCY_CHECKS)
   for(DenseIndex d: varDims) {
     assert(d != numeric_limits<DenseIndex>::max());
   }
diff --git a/gtsam/nonlinear/ISAM2-impl.cpp b/gtsam/nonlinear/ISAM2-impl.cpp
index a0fc117d9..3b5156535 100644
--- a/gtsam/nonlinear/ISAM2-impl.cpp
+++ b/gtsam/nonlinear/ISAM2-impl.cpp
@@ -291,9 +291,10 @@ size_t ISAM2::Impl::UpdateGaussNewtonDelta(const FastVector<ISAM2::sharedClique>
       lastBacksubVariableCount += optimizeWildfireNonRecursive(
       root, wildfireThreshold, replacedKeys, delta); // modifies delta
 
-#ifdef GTSAM_EXTRA_CONSISTENCY_CHECKS
-    for(size_t j=0; j<delta.size(); ++j)
-      assert(delta[j].unaryExpr(ptr_fun(isfinite<double>)).all());
+#if !defined(NDEBUG) && defined(GTSAM_EXTRA_CONSISTENCY_CHECKS)
+    for (VectorValues::const_iterator key_delta = delta.begin(); key_delta != delta.end(); ++key_delta) {
+        assert(delta[key_delta->first].allFinite());
+    }
 #endif
   }
 
diff --git a/gtsam/nonlinear/ISAM2-inl.h b/gtsam/nonlinear/ISAM2-inl.h
index f04e16b7d..fecefd2a5 100644
--- a/gtsam/nonlinear/ISAM2-inl.h
+++ b/gtsam/nonlinear/ISAM2-inl.h
@@ -44,7 +44,7 @@ void optimizeWildfire(const boost::shared_ptr<CLIQUE>& clique, double threshold,
 
   // Are any clique variables part of the tree that has been redone?
   bool cliqueReplaced = replaced.exists((*clique)->frontals().front());
-#ifdef GTSAM_EXTRA_CONSISTENCY_CHECKS
+#if !defined(NDEBUG) && defined(GTSAM_EXTRA_CONSISTENCY_CHECKS)
   for(Key frontal: clique->conditional()->frontals()) {
     assert(cliqueReplaced == replaced.exists(frontal));
   }
@@ -121,7 +121,7 @@ bool optimizeWildfireNode(const boost::shared_ptr<CLIQUE>& clique, double thresh
 
   // Are any clique variables part of the tree that has been redone?
   bool cliqueReplaced = replaced.exists(clique->conditional()->frontals().front());
-#ifdef GTSAM_EXTRA_CONSISTENCY_CHECKS
+#if !defined(NDEBUG) && defined(GTSAM_EXTRA_CONSISTENCY_CHECKS)
   for(Key frontal: clique->conditional()->frontals()) {
     assert(cliqueReplaced == replaced.exists(frontal));
   }