Revealed: How top scientists now think you can ‘catch’ depression and anxiety like you would a cold – here’s how to protect yourself

Could misery be contagious? There is no doubt that the number of Britons complaining of low mood and depressive symptoms, such as sadness and a sense of helplessness, is skyrocketing.

Latest research figures from the Office for National Statistics show that one in six report moderate or severe depressive symptoms, up 60 per cent on the previous three years.

This huge increase has been attributed in various ways to the mounting mental pressure caused by the Covid-19 lockdowns and the subsequent cost of living crisis.

But could the snowballing rate of depression have another cause? Could depression be contagious — something you can “catch,” like a cold or the flu?

That is the idea put forward by Finnish psychologists in the renowned journal JAMA Psychiatry.

The team, led by Christian Hakulinen, an associate professor of psychology at the University of Helsinki, followed the health records of more than 700,000 children for 11 years, starting at age 16.

Their analysis found that if one student in a class showed clear signs of depression, his or her classmates were at least 9 percent more likely to also develop depression.

People with more than one affected classmate were at least 18 percent more likely to be diagnosed themselves during the 11-year study.

Even when the figures were adjusted for factors that could influence outcomes, such as income, the link between a depressed student and an increase in depression among classmates remained.

In fact, although the influence diminished over time, it persisted for eleven years after the students left school.

Previous research has also shown that depression can be contagious.

For example, a 2014 U.S. study in the journal Clinical Psychological Science showed that depressive thoughts can spread between college roommates. Psychologists at the University of Notre Dame, Indiana, studied 108 new college students who were randomly assigned to share rooms as pairs.

The students completed an online survey about their thinking styles, stress exposure and mood in their first month, and again three and six months later. In particular, the researchers studied a type of thinking linked to depression called rumination, which involves worrying about things.

The researchers found that if a roommate had started their college years with a habit, their previously non-worrier roommate often picked up the habit. They also had more than twice as many depressive symptoms as non-worriers.

As Dr Jack Andrews, a developmental psychologist at the University of Oxford who researches this phenomenon of social contagion, explains: ‘Depression can indeed spread through shared rumination: the sharing of the process of repeatedly holding on to negative thought processes and catastrophizing, without finding a solution.’

And it’s not just students who are susceptible, as Dr Andrews told Good Health: ‘Scientists have found evidence of this on social networking sites, where you can map relationships between individuals. They show that moods spread among adults too.’

He points to further evidence of emotional contagion from the Framingham Study, which has been collecting medical information on the residents of Framingham, Massachusetts, since 1948.

“The researchers collected information about depressive symptoms, such as low mood and hopelessness, and asked people to name their closest friends and family members,” Dr. Andrews said.

‘In 2012, researchers mapped the city’s social network to track which people spent time together, and then looked to see if there was a correlation between levels of depressive symptoms among friends.’

In 2010, psychiatrists at Harvard Medical School wrote in the journal Molecular Psychiatry that Framingham residents were more likely to have depressive symptoms if a close friend also had them.

Dr. Andrews adds: ‘This was true even across three degrees of separation: having a depressed friend of a friend of a friend also increases the likelihood of depression.’

And it wasn’t just the depressed moods that occurred among friends: the same pattern was found for levels of happiness.

Scientists are still debating the mechanisms by which depression might be contagious.

Last year, Dr Andrews and colleagues published their theory of ‘prevalence inflation’, which suggested that the increasing public and social media discussion of mental health issues could lead to more people believing they have a mental illness.

“This may mean that more people are recognizing real symptoms and seeking help,” he says. “But it may also mean that people are misidentifying normal, everyday low mood as depression — thinking they are ill when they are not. This hypothesis needs to be tested.”

Additionally, Dr. Andrews says depression can be seen as “cool” by some groups.

‘Research into ‘outsider’ youth groups, such as Goths, shows that members adapt their behaviour to strengthen their sense of community,’ he explains.

‘In this way, individuals can adjust their moods to enhance their sense of belonging to a group. This occurs especially in adolescents.’

There are other theories. In 2022, researchers in Brazil suggested that we are programmed to pick up on each other’s depressive emotions via specialized brain cells called mirror neurons.

Brain scanning studies have shown that when a person watches another person do something, such as sawing wood or dancing, that person’s mirror neurons activate the rest of their brain, “training” them to perform the task in a similar way.

The Brazilian researchers wrote in the journal Neuroscience & Biobehavioral Reviews that people mirror each other’s emotions in a similar way.

Other research shows that we can even pick up depression from each other through our sense of smell. That is, we smell it on each other.

Scientists have already established that other emotions, such as fear and disgust, can also be contagious in this way.

In 2012, psychologists at Utrecht University exposed women to cotton swabs containing sweat from men who had just watched a frightening or disgusting film clip.

The women had to perform a computer task while unconsciously smelling the men’s sweat. The researchers recorded their facial expressions.

In the journal Psychological Science, the researchers reported that the women exposed to the sweat of the men in the fearful group were more likely to open their eyes with a fearful expression on their faces, while the women who sniffed the sweat of the disgusted group were more likely to contort their faces in disgust.

The idea that pheromones – chemical signals that people and animals send out to communicate with each other – can spread depressive moods comes from preliminary research on the science website Research Square.

Scientists at the Fourth Military Medical University in China reported last year that they discovered that depressed lab mice secrete a pheromone in their urine called Major urinary protein 1. This pheromone causes other mice to become wary and unsociable when they smell it.

The researchers suggest that humans have a similar pheromone, the human progestin-associated endometrial protein (hPAEP), which may be linked to antisocial behavior in humans.

It should be emphasized that this is preliminary research that has not been reviewed by independent experts.

But however depressive feelings spread, we must strive to build resilience against them, says Professor Vivian Hill, director of professional training in educational psychology at the UCL Institute of Education.

She says of the latest Finnish research: ‘It seems that in groups there is a leech effect, where emotions can spread.’

She would like to see mental health and coping strategies included in school curricula.

Adults need to build resilience, too, she says. “If you find a particular experience challenging, ask yourself, ‘How can I deal with it in a more positive way?’”

“Your answer may lie in going to the gym or having positive conversations with friends. Just as we need to exercise and eat healthy for our bodies, we need to do healthy things for our minds.”

Eat more…

Ginger: Ginger may help you lose weight, according to a study in the journal Nutrition Reviews. The study analyzed the results of 27 previous studies on the effects of ginger on weight. It found that eating 2 grams of ginger per day for at least eight weeks led to significant weight loss.

Possible mechanisms include an anti-inflammatory effect and substances that influence fat burning and storage processes.