According to a report by the Office of National Statistics (ONS), one in five adults in England and Wales suffered abuse before the age of 16.
The research studies emotional, physical and sexual abuse, from threats and contempt to beatings and rapes.
The ONS estimates that 8.5 million people between the ages of 18 and 74 were abused or witnessed abuse as children.
About 14% of adults who called a charity helpline last year had not told anyone before.
The research was compiled with data from the Department of Education, the Government of Wales, the National Society for the Prevention of Cruelty against Children (NSPCC) and the National Association for Abused Children (Napac), which runs the line of help
Its objective is to provide a better understanding of the scale and nature of child abuse.
- Children in charitable homes “suffered abuse”
- Record number of images of child sexual abuse treated
There is no single definition of child abuse, and the report includes a variety of crimes or negative experiences.
It includes sexual abuse, such as rape and other assaults such as indecent exposure; physical abuse, such as throwing objects and hitting; and emotional abuse, including behavior that suggests that a child is not loved.
The report also takes into consideration people who witnessed any of these forms of abuse as children.
It shows that at the end of March last year, more than 54,000 children were under the care of local authorities in England and Wales because they had experienced or were at risk of abuse.
In the year before March 2019, Childline gave 19,847 counseling sessions to children in the United Kingdom, where abuse was the main concern.
That is a slight drop compared to the previous year, when there were 22,133 counseling sessions for this reason.
By Tom Symonds, internal affairs correspondent
The most significant of today’s research is that it suggests that 8.5 million people have not only experienced abuse, but may be living with the effects of a lifetime of suffering.
Sexual abuse, in particular, can have an impact throughout adulthood, resulting in failed relationships, participation in crime, depression and suicide.
Any of the victims may need help later in life, and experts working in the field are increasingly talking about the need for what they call “informed about trauma” support.
In other words: help for adults that takes into account the experiences they had as children.
Regarding the prevention of child abuse, this investigation could increase the pressure for the so-called mandatory reports, which makes it a legal obligation for people working with children to report evidence of abuse.
Ongoing public investigation into child sexual abuse seems increasingly likely to support it.
Findings on adults who suffer abuse as children were compiled using data from the Crime Survey for England and Wales (CSEW).
However, the CSEW underestimates the total number of adults who were abused as children because the abuse against 16 and 17 year olds does not count.
The ONS report also found that half of the adults (52%) who suffered abuse as children also experienced domestic abuse later. Of those who did not experience abuse as children, the figure was 13%.
The research also reveals:
- 3.1 million people, 7.5% of adults, suffered sexual abuse as children.
- About one in four women suffered abuse before the age of 16 compared to one in six men.
- 32% of CSEW respondents who had a mixed or multiple ethnic identity experienced abuse as children, compared with 21% of white respondents, 17% of black respondents and 11% of Asian respondents.
- Children living with adults with a long-term health condition, disability, mental health condition, problem drinkers or drug users were more likely to have suffered abuse.
- 52,260 children in England were subject to a Child Protection Order in March last year.
Alexa Bradley, of the ONS Center for Crime and Justice, said: “Child abuse is a terrible crime against some of the most vulnerable in society, but it is also something that is little discussed or understood.
“Today’s launch is the first attempt by ONS to fill a void of important evidence on this critical issue.”
NSPCC spokesman Andrew Fellowes said the report shows how the “devastating effects” of child abuse can affect victims in adulthood, but said it is still unclear how many children “are suffering at this time.”
“It is crucial that the government conduct a prevalence study to get a true picture of the scale of abuse in the United Kingdom,” he said.
“Only then will we know what services are necessary to protect and support abused youth.”
If you or someone you know has been affected by these problems, you can get help and support at bbc.co.uk/actionline