diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index a24dd04..493fa87 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -2839,7 +2839,8 @@
 				When omitted a context of six lines is used.
 				When using zero the context is actually one,
 				since folds require a line in between, also
-				for a deleted line.
+				for a deleted line. Set it to a very large
+				value (999999) to disable folding completely.
 				See |fold-diff|.
 
 		iblank		Ignore changes where lines are all blank.  Adds