diff --git a/lib/memdebug.c b/lib/memdebug.c
index 3e3c1bc..be49f53 100644
--- a/lib/memdebug.c
+++ b/lib/memdebug.c
@@ -138,11 +138,8 @@ void *curl_domalloc(size_t wantedsize, int line, const char *source)
   size = sizeof(struct memdebug)+wantedsize;
 
   mem = (Curl_cmalloc)(size);
-  if(mem) {
-    /* fill memory with junk */
-    memset(mem->mem, 0xA5, wantedsize);
+  if(mem)
     mem->size = wantedsize;
-  }
 
   if(source)
     curl_memlog("MEM %s:%d malloc(%zd) = %p\n",
@@ -166,12 +163,9 @@ void *curl_docalloc(size_t wanted_elements, size_t wanted_size,
   user_size = wanted_size * wanted_elements;
   size = sizeof(struct memdebug) + user_size;
 
-  mem = (Curl_cmalloc)(size);
-  if(mem) {
-    /* fill memory with zeroes */
-    memset(mem->mem, 0, user_size);
+  mem = (Curl_ccalloc)(1, size);
+  if(mem)
     mem->size = user_size;
-  }
 
   if(source)
     curl_memlog("MEM %s:%d calloc(%zu,%zu) = %p\n",
@@ -260,9 +254,6 @@ void curl_dofree(void *ptr, int line, const char *source)
 #  pragma warning(pop)
 #endif
 
-  /* destroy  */
-  memset(mem->mem, 0x13, mem->size);
-
   /* free for real */
   (Curl_cfree)(mem);