In the mid-1980s, doctors running a weight loss programme at a clinic in San Diego happened upon a startling discovery.
Struggling to understand why successful slimmers were quitting, lead physician Dr Vincent Felitti began interviewing the leavers and found many had experienced sexual abuse in childhood.
His findings led to a conclusion that would have major implications for public health – overeating was being used unconsciously as a protection from trauma suffered early in life.
Contrary to all the medical evidence, it seemed obesity did provide benefits for some; it helped people deal with physical, sexual or emotional experiences they had undergone as children.
It was out of Felitti’s research that the Adverse Childhood Experiences (ACEs) Study was born. Between 1995 and 1997, 17,000 Californians were surveyed on their physical health alongside questions about their childhoods.
The study found that as the number of ACEs increased, so did the incidence of depression, alcoholism, promiscuity and suicide attempts in later life.
A bold interpretation of the results was that trauma endured during childhood was the main determinant for the health and wellbeing of adults.
More than 20 years on from that landmark study, the concept of ACEs has moved centre stage.
The idea has been enthusiastically adopted by the Scottish Government, teachers, psychologists and even Police Scotland.
Supporters speak of making Scotland the world’s first “ACE-aware” nation, believing negative childhood experiences can help explain everything from smoking to criminality.
But while few deny that childhood trauma can have a profound and long-lasting impact, there is growing controversy over the adoption of the ACEs agenda, which some experts argue fails to take account of socio-economic conditions and can unfairly stigmatise children.
It is claimed that ACEs have been seized upon as a “magic bullet” in an era when teachers, social workers and police officers have been left bereft by the impact of austerity, desperately reaching for something, anything, to help tackle deep-seated social problems.
According to the Centers for Disease Control and Prevention, the US public health institute which carried out the original study, there are 10 ACEs.
They include emotional or physical neglect; emotional, physical or sexual abuse; divorce; domestic violence; imprisonment of a family member; living in a household where there is drug or alcohol abuse; or where there is experience of mental illness.
By adding together the number of areas of adverse experience suffered before a person’s 18th birthday, it is possible to attribute to someone an “ACE score”.
The Scottish Government cites research from Wales which suggests people who experience four or more ACEs are four times more likely to be a problem drinker, three times more likely to develop heart disease, 15 times more likely to commit violence and 20 times more likely to go to prison.
Developmental psychologist Dr Suzanne Zeedyk, an honorary fellow at Dundee University, has been at the forefront of promoting awareness of the impact of childhood trauma.
She believes growing Scottish interest is the result of a grassroots movement driven by social media which has seen teachers, social workers and police officers come together for screenings of an American documentary, Resilience, which explores the impact of stress on the body.
She estimates that upwards of 20,000 people have watched the film, 200 alone at showings put on by schools in West Lothian last week.
“What’s important from the ACEs research is not those 10 examples of adverse experiences but the understanding that fear changes your biology,” she says.
“There has been a light bulb moment from the ACEs study. We have known that a troubled childhood can make your adulthood difficult, people intuitively get that.
“What we thought was that it led to mental health difficulties, that you’d be more likely to be depressed or attempt suicide, that you might find relationships difficult.
“But most people are surprised to learn that childhood distress makes it more likely you’ll have a heart attack, that you’ll get cancer, that your risk of diabetes is increased. Most people are surprised by that – it hasn’t been part of our cultural awareness.”
There is indeed growing evidence that early and prolonged trauma can have a devastating impact on a child’s biological development.
Exposure to so-called “toxic stress” is known to reduce neuro-connections in parts of the brain responsible for learning and reasoning.
According to researchers at Harvard University, in cases of chronic abuse – especially during early, sensitive periods of brain development – the parts of the brain involved in fear, anxiety, and impulsive responses can overproduce neural connections while those regions dedicated to reasoning, planning, and behavioural control go into decline.
The science indicates that the mere presence of a loving adult can prevent elevations of the stress hormone cortisol in toddlers, providing a powerful buffer against this neurological onslaught.
“We are talking about childhood distress in a way we have not done before,” says Zeedyk. “I see this as a real opportunity for our country to pay closer attention to distress. It’s ACEs that have got us interested, it has engaged people’s interest.
“Some of my colleagues are worried that the framework of ACEs could distract the government from looking at poverty. In other words, if we blame the parents, it takes our eyes off poverty. But I think ACEs lets us look at both, I don’t think it makes us choose.”
The challenge for the ACE-aware and the “trauma-informed” is how they now use that information to alleviate childhood suffering and treat adults still dealing with the impact of abuse earlier in life.
One example of what the future might look like comes from an unlikely source.
Earlier this month, officers from Police Scotland’s Ayrshire division told a meeting of the Scottish Police Authority how the unit had become trauma-informed at a cost of less than £5,000.
Officers were shown the Resilience documentary in the hope that learning about the impact of adverse experiences in childhood will help inform the work of a force which estimates that 80 per cent of its work relates to non-criminal matters.
To an ageing population – growing numbers of them with dementia – add the impact of cuts to mental health provision and you’re left with police officers fielding increasing numbers of calls relating to missing persons and people in distress.
Society’s growing awareness of historical sexual abuse has also significantly contributed to the caseload as more adults come forward to report the trauma they have been living with for decades.
“More and more officers are dealing with homelessness, eviction, mental health and poverty,” says Ayrshire divisional commander Detective Superintendent Paul Main.
“Unless we understand the life experiences people have or the trauma they’ve suffered, we’re not going to deliver as good a service as we should.”
Main uses the example of a man who was arrested and due to appear in court. Police officers had taken the time to ask questions and found out the man had an addiction worker who was able to “scoop up” his client when he left court.
“Instead of that person coming out of court and into a cycle of crime, alcohol or drugs, they had someone who cares about them and could take care of them,” says Main.
The detective superintendent likes to repeat the mantra “Adversity is not destiny”, knowing that just because a person has had a tough start in life doesn’t mean they will become a career criminal.
“We could keep locking people up and throwing away the key and they would come out and commit more crime. I don’t think that’s the right approach. We absolutely need to arrest and incarcerate a small group of people some of the time, but for the vast majority, the best way of keeping people safe is to find ways of preventing crime or the reasons for the crime in the first place.”
But amid all the positivity there are those sounding notes of caution, particularly about the dangers of overlooking the pernicious effects of poverty.
Research published last week by Edinburgh University found two-thirds of children in Scotland have suffered an adverse life event by their eighth birthday, while one in 10 have experienced at least three such traumatic events in their lifetime.
Dr Louise Marryat, who carried out the research, says her study shows those living in disadvantaged circumstances are particularly at risk.
“Up until now, there’s been a lot of talk about adversity being experienced across the population, which is true. However, these results seem to be suggesting it is particularly concentrated in children who live in low-income households and who experience other forms of disadvantage,” she says.
“It’s a really important thing to keep in mind that this isn’t a deterministic thing – it’s not the case that you experience ACEs and you will end up with these outcomes.
“It should be used as a tool on a population level, not for individuals. People who experience four or more ACEs are at higher risk of developing physical and mental health conditions, but it’s not inevitable.”
Marryat says there is some anecdotal evidence of ACE scores being used to screen children in schools.
“I think we should be concerned if it’s being used in that way,” she adds. “We know how difficult it is to get access to child and adolescent mental health services as it is. If the support isn’t there, I think that’s quite worrying.
“There is a view, I’m not necessarily saying it’s my view, that our resources are so limited at the moment that it’s very hard to deal with these big issues and the ACE scale makes it feel like we’re doing something.
“I think the people that are proposing this are doing it with the best intentions. People genuinely want things to be better for children in Scotland. Whether this is the best approach for that, I’m not sure I agree.”
Others are far more critical. The Problem With ACEs was an academic paper submitted to the House of Commons’ Science and Technology Committee’s inquiry into early years intervention.
Its authors said “alarm bells should ring” when advocates begin talking in evangelical terms about ACEs.
The paper states: “These are often social problems which have been occurring and been responded to by policy-makers and politicians for at least 150 years: crime, drunkenness, mental health problems, violence. This is not to say that nothing can or should be done but that there is no such thing as a magic bullet intervention.”
Rosalind Edwards, a professor of sociology at Southampton University and one of the paper’s authors, has a number of misgivings about the way the original ACE Study is now being applied.
“The studies that were done that people rely on to show that there are adverse outcomes from adverse circumstances, they were scientific studies done at population level,” she says.
“They talk about the risk, the probability that people will have these bad outcomes in later life. They cannot be applied to an individual. You cannot point to an individual child and say they are having dreadful things happen to them so they will have dreadful outcomes later in life. But that’s happening because it’s being translated into tick box protocols where teachers or social workers are encouraged to tick how many adverse circumstances children have and then they are given an ACE score. That is a fundamental misunderstanding of what you can do on the basis of the science.”
Edwards worries that ACEs are being applied in a deterministic way – she notes that a person can have no ACEs and still turn out to be “quite dysfunctional”. The opposite is also true.
“I don’t wish to say that people don’t have goodwill in implementing ACEs and it may give the police, teachers and social workers something firm to hold on to, but actually they are grasping at a straw person.
“I would encourage them to row back from it. You need to understand what the science is telling you and what it is not telling you. It’s tough in times when finances are difficult, but actually just investing in human services and a humane approach is what you need. You don’t need ACEs to do that.”