World Friendship day- why it is bad to be lonely

30th July was designated
International day of friendship by the United Nations

The original resolution seeks to promote understanding and bridges between communities

however friendship is also important to the mental health and well being of individuals. failture to address their needs impacts on the eocnomic and social well being of societies.
It can be difficult to define what constitutes social isolation. this paper  Oxford Poverty & Human Development Initiative 2014 considers the issues from an international angle

UK government strategies/ policies to reduce loneliness

the Campaign to End Loneliness has a research hub that links to recent examples of loneliness research
they cite a number of facts about negative impacts.
IoTUK has published a report on how technology might help

 Old Age
AgeUk has published an evidence review from 2015 which examined the literature
there is a 32 page summary
their website also has other articles and maps the latter including mapping of loneliness in neighbourhoods
Ambition for Ageing has said that BAME individuals are often overlooked they published a report on the situation in Greater Manchester
Silverline loneliness surveys- charity offering telephone helpline

Carers 

CarersUK report on the issues faced.

Families

A report looking into the impact of loneliness in children, young

people and families- NCH Children

search for more reports on the medical impact using NHS evidence . these include NHS documents as well as journal articles many in full text

Pubmed has references from the Medline database relating to medical journal articles.