Mass of All the People on Earth
Bibliographic Entry  Result (w/surrounding text) 
Standardized Result 


Boone, Kevin. Standard Man: Average (male) values for various biophysical values. The Kzone. 

70 kg  
The World Almanac, Book Of Facts. 1997. 538.  "The total world population for the year 1997 is 5,772,000,000 people."  5,772,000,000 people  
Durney, Carl H. Habib Massoudi, & Magdy F. Iskandy. Average Height, Dosimetry Handbook. University of Utah, October 1986. 

Male: 70.00 kg Female: 61.14 kg 

Heaviest Man. Guinness Book of World Records. 16 May 2006.  "In March 1978, [Jon Brower] Minnoch was admitted to University Hospital, Seattle, where consultant endocrinologist Dr. Robert Schwartz calculated that Minnoch must have [a mass of] more than 635 kg, a great deal of which was water accumulation due to his congestive heart failure."  635 kg  
World Population hits 6.5 Billion. MSNBC. 25 February 2006.  "At 7:16 p.m. ET on Saturday, the population here on this good Earth hit 6.5 billion people, according to projections."  6.5 billion 
The world is an immense place. With more than 6.5 billion people on earth, and that number increasing every day, the amount of mass of all these people is enormous. These people, who cover the entire planet, have a lot of mass. Even though each person is miniscule when compared to the planet as a whole, when looked at in their entirety, people make up a significant amount of mass.
The average adult male is 70 kilograms and the average adult female is just over 61 kilograms. this averages out to about 65 kilograms for the average person. to find the mass of all the people on the earth, you must multiply the number of people times their average mass. So 65 kilograms times 6.5 billion people equals 422.5 billion kilograms, or approximately one trillion pounds.
When compared to the mass of the earth, 6x10^{24} kilograms, it can be seen that while massive, the mass of all the people on the earth makes basically no difference to the mass of the earth. The mass of all the people on the earth is equal to one and a half trillionth the weight of the earth. While the number of people on the earth keeps increasing, it can be assumed that while the population may make it into the tens of billions, it will never amount to enough to noticeably affect the earth's rotation.
Daniel Touger  2006