Loneliness is becoming an epidemic, with millions feeling they have no one to turn to.
Over nine million people in the UK, more than the population of London, are “always or often” lonely, according to the Campaign to End Loneliness.
Old people are among the worst affected, with two-fifths (around 3.9 million) having just a TV for company.
While the toll on our mental health is well known, loneliness can also affect us physically, with one study suggesting it may have the same effect as smoking 15 cigarettes a day.
“It’s not easy to spot someone who is lonely,” Dr Kalpa Kharicha, head of innovation policy and research at the Campaign to End Loneliness, told Yahoo UK.
“They’re not visible when you see someone on the street.
“No one wants to be known as a lonely person.
“They wear a mask because you want to present yourself in a certain way.”
While it can be tricky to spot, certain groups of people are more vulnerable.
“Living on your own, the bereaved, those in poor health that stops them getting outdoors, caring for somebody because it reduces your ability to look after your networks, people who’ve moved away,” Dr Kharicha said. “These are all triggers.”
Old people are thought to be particularly at risk, with half a million in the UK reportedly speaking to no one on up to six days a week.
Depression and loneliness are separate issues but can go hand-in-hand, with one often triggering the other, Dr Kharicha added.
The mental-health disorder can be easier to spot, with a set of recognised symptoms.
Depressed people often turn down social gatherings and avoid activities they once enjoyed, according to the charity Mind.
Some may also struggle to speak, think clearly or make decisions. Many are turned off sex and rely on cigarettes or alcohol to get through the day.
Others are constantly exhausted, move slowly, and even complain of constipation or unexplained aches and pains.
Eating too much or little, leading to weight gain or loss, should also raise alarm bells.
How to help someone battling loneliness
Loneliness is serious, being linked to everything from dementia and heart disease to even an early death.
You don’t have to feel helpless if you suspect someone is struggling, with even small gestures going a long way.
“Make small talk, offer a cup of tea to someone on your street, make conversation while waiting for the bus,” Dr Kharicha told Yahoo UK.
While it may not sound like much, a small act of kindness can make a big difference to someone who feels alone.
“It shows openness,” Dr Kharicha said. “Small gestures, listening and talking, can be very meaningful.”
When it comes to older people, the NHS recommends offering to lend a hand, whether it be picking up prescriptions, changing a light bulb or giving them a lift to a doctor’s appointment.
With many struggling to cook for themselves, you could also invite them over for dinner or freeze leftovers for them to reheat, the health service adds.
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Encouraging people to take part in activities in their local area can also help, whether it be volunteering, joining a book club or singing in a choir.
“Anything that strengthens connection in communities,” Dr Kharicha said.
If that feels too much, just making an effort to catch up with someone over a drink can have a big impact.
“Pubs and clubs can be brilliant places to come together,” Dr Kharicha said.
While many of us are glued to our phones, the expert stresses the importance of meeting up in the flesh.
“It should never replace human contact,” she said. “We’re social beings.
“You don’t want to spend so much time on your gadget that you forget how to communicate in the real world.”
Dr Kharicha adds, however, phones can play a part in bringing people together.
“The internet can be a way of staying in touch and you can share interests in online communities,” she said.
“It can be an ‘extra’ but shouldn’t replace human interaction.”
If you are struggling, the Samaritans are available 24/7 on 116 123.