Loneliness is seen as a big problem for the mental health of the population. Which age group suffers most from the loneliness? Which section of the society is most affected by loneliness?

You can get the answer after watching that video from BBC Learning English: People age between 16 and 24 experience loneliness more often and more intensely than any other age group. The feeling lonely may plague the young because it's time to identity change, figuring out their place in the world and learning to regulate emotions.