The average weight of an adult’s head is 5kg. That is if the head is stacked up right, using the spine to support it in the ideal alignment.
But recent studies show, that with prolonged time with the head poked forwards, such as when on the computer or smartphone, the increased lever relatively increases the weight of the head to up to 27kg. No wonder so many people experience persistent, severe neck pain and headaches.
Similarly, sustained overloading postures, such as standing in prolonged slumped or swayed postures, or constantly standing with weight more on one side of your body than another (such as always holding you baby on the same hip).