diff --git a/Misc/NEWS b/Misc/NEWS
index 8c752a7..c690dea 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,11 @@
 Core and Builtins
 -----------------
 
+- Issue #4688: Add a heuristic so that tuples and dicts containing only
+  untrackable objects are not tracked by the garbage collector. This can
+  reduce the size of collections and therefore the garbage collection overhead
+  on long-running programs, depending on their particular use of datatypes.
+
 - Issue #5512: Rewrite PyLong long division algorithm (x_divrem) to
   improve its performance.  Long divisions and remainder operations
   are now between 50% and 150% faster.