The average weight of a human being is 62 kg (136 lbs). There are extremes on both sides with many countries particularly dealing with an obesity problem.
Generally, the more developed countries tend to weigh more, mostly because of their eating culture. Countries like the US and Canada consume a lot of fried foods and junk food, unlike countries for example in Africa and Asia.
These graphics show how much people in select countries weigh.
Source: Nairobi Wire