diff --git a/docs/en/docs/advanced/custom-response.md b/docs/en/docs/advanced/custom-response.md
index e88e958657..b7131aa0b3 100644
--- a/docs/en/docs/advanced/custom-response.md
+++ b/docs/en/docs/advanced/custom-response.md
@@ -167,7 +167,19 @@ You can also use the `status_code` parameter combined with the `response_class`
 
 Takes an async generator or a normal generator/iterator and streams the response body.
 
-{* ../../docs_src/custom_response/tutorial007_py310.py hl[2,14] *}
+{* ../../docs_src/custom_response/tutorial007_py310.py hl[1,4,11,17] *}
+
+/// note
+
+Notice the `await asyncio.sleep(0)` inside the async generator function.
+
+In asyncio, a running task only yields control back to the event loop when it hits an `await`. Without any `await` expression, the generator would hold the event loop for the entire iteration, preventing the response from being streamed chunk by chunk and also preventing proper task cancellation.
+
+Adding `await asyncio.sleep(0)` is a lightweight way to give the event loop a chance to send each chunk to the client and handle cancellation between iterations.
+
+If your generator doesn't have any natural `await` points, consider using a **normal (synchronous) generator** with `def` instead to avoid this issue.
+
+///
 
 #### Using `StreamingResponse` with file-like objects { #using-streamingresponse-with-file-like-objects }
 
diff --git a/docs_src/custom_response/tutorial007_py310.py b/docs_src/custom_response/tutorial007_py310.py
index e2a53a2119..0c17ce40ee 100644
--- a/docs_src/custom_response/tutorial007_py310.py
+++ b/docs_src/custom_response/tutorial007_py310.py
@@ -1,3 +1,5 @@
+import asyncio
+
 from fastapi import FastAPI
 from fastapi.responses import StreamingResponse
 
@@ -6,6 +8,7 @@ app = FastAPI()
 
 async def fake_video_streamer():
     for i in range(10):
+        await asyncio.sleep(0)
         yield b"some fake video bytes"