“Happy Birthday to You” is a popular birthday song. At the end of the verses, instead of “cha-cha-cha” (cited in print since at least 1959), some people scream, “Chinese food!” The “Chinese food” addition has been cited in print since the 2000s.
   
   
Wikipedia: Happy Birthday to You
“Happy Birthday to You”, more commonly known as simply “Happy Birthday”, is a song that is traditionally sung to celebrate the anniversary of a person’s birth. According to the 1998 Guinness World Records, “Happy Birthday to You” is the most recognized song in the English language, followed by “For He’s a Jolly Good Fellow”. The song’s base lyrics have been translated into at least 18 languages. The melody of “Happy Birthday to You” comes from the song “Good Morning to All”, which has traditionally been attributed to American sisters Patty and Mildred J. Hill in 1893, although the claim that the sisters composed the tune is disputed.
 
Patty Hill was a kindergarten principal in Louisville, Kentucky, developing various teaching methods at what is now the Little Loomhouse; her sister Mildred was a pianist and composer. The sisters used “Good Morning to All” as a song that young children would find easy to sing. The combination of melody and lyrics in “Happy Birthday to You” first appeared in print in 1912, and probably existed even earlier.
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Lyrics
“Happy birthday to you”
Happy birthday to you
Happy birthday to you
Happy birthday dear [NAME]
Happy birthday to you.
       
OCLC WorldCat record
Happy birthday cha cha cha.
Author: Miny Gerard; Bob Azzam
Publisher: S.L. : Festival, [195?]
Edition/Format:   Music : 45 rpm : Multiple languages
 
13 May 1959, Tucson (AZ) Daily Citizen, pg. 32, col. 8:
Tucson High
Arriving at Sabino Canyon to hear “Happy birthday to you, cha-cha-cha,” sung by 20 girls, made perky Carroll Gommell realize that everyone gathered to wish her a happy 17th birthday.
 
4 August 1959, New York (NY) Herald Tribune, “Hy Gardner Calling,” pg. 10, col. 7:
We even exchanged noddings with several familiar faces at the Lido where they were dancing to “Alexander’s Ragtime Band Cha-Cha,” “Tea for Two Cha-Cha” and “Happy Birthday to You Cha-Cha.”
   
Google Books
Kingdom of Illusion
By Edward R. F. Sheehan
London, UK: Chapman & Hall
1965, ©1964    
Pg. 92:
Happy Birthday to you cha cha cha.
 
Straight Dope Message Board
When was “cha cha cha” added to the “Happy Birthday Song”?
reborndata
11-01-2004, 09:16 PM
As a relatively recent parent, I have been attending my first children’s birthday parties in over a decade, and have noticed that nearly all children now add “cha cha cha” to the end of each line in the song. As in:
 
“Happy Birthday to you… cha cha cha!” (etc…)
 
This addition is new to me, but it is so pervasive, it has left me wondering what recent cultural phenomenon I managed to completely miss. I’ve searched the web in vain… can anyone shed light on where it might have originated and how it spread so quickly?
 
YouTube
Happy Birthday Cha Cha Cha
12thDecember
Published on Oct 25, 2009
Not your typical Happy Birthday video. NOT intended for children.
 
YouTube
Happy Birthday Cha Cha Cha
ijhproductions
Published on May 18, 2010
Isaac’s 3rd birthday party with a cha cha cha birthday song!
 
mommyandmaddie
Chinese Food
Posted by: mommyandmaddie | April 1, 2011
Would you be insulted?
 
Whenever my nephews get together for a birthday party, they sing happy birthday. but the song goes like this..
 
Happy Birthday to you… CHINESE FOOD!
Happy Birthday to you… CHINESE FOOD!
etc…
 
The Chinese food is in replacement of the usual CHA-CHA-CHA and they SCREAM it at the top of their lungs.
 
They used to always sing cha-cha-cha but the first time i heard it changed was a few years ago at my nieces birthday party. At first I didnt know what they were saying since they were screaming it so loud. but then i started to think they were saying “chinese food”.
 
Twitter
Mike Cappelluti‏
@MikeCappelluti
“Happy birthday to you CHINESE FOOD”- dean 😊 http://vine.co/v/bwpXQLUVY2X
5:22 PM - 10 Mar 2013
 
Twitter
andrew‏
@ravioliiii
Remember when u used to say “chinese food” in between verses of the birthday song
6:28 AM - 4 Jun 2013
 
Twitter
hot 90s boy‏
@jakeismean
Happy birthday to you, happy birthday Chinese food
4:08 PM - 2 May 2014
 
AnandTech—Forums
Happy Birthday to you… “chinese food”?
Discussion in ‘Off Topic’ started by rh71, Feb 5, 2017.
Why are kids today saying this when they sing happy birthday to someone? They scream chinese food at the end of each line. Where did this come from? Or do we just know a bunch of weird kids in this town? Have heard this over 3 years at various bday parties now…
#1rh71, Feb 5, 2017