Plenty of research shows men make friends less easily than women, and take part in fewer social activities.
And it is something worth knowing if you're a young man, as it can worsen with age.
The impacts can be devastating, with extensive research showing that this kind of isolation correlates to higher levels of depression and anxiety.
"Ladies normally run our social network, so when you guys disappear we are stuffed," says Australian Men's Shed Association project officer Stuart Torrance.
As well as a couple's social network largely "belonging to the wife", Mr Torrance says men operate in networks that diminish over time.
Men also make the majority of their connections through work, Relationships Australia Mensplace coordinator Mark Burrage says. So when that disappears, so does their social life.
And for the small number of friends they do have, a reluctance to open up prevents those relationships from becoming more "sticky", according to beyondblue.
"Men are raised to be self-reliant and 'bulletproof' … so they don't tend to reach out as much," Mr Burrage says.
Don't want this to be you?
The good news is there are ways to address loneliness, plus habits you can develop as a young man to maintain and develop new friendships as you age.
Habits to help you avoid loneliness
Build long-term networks
"Set up networks that aren't going to diminish — that aren't centred around an activity," Mr Torrance says, giving the example of seeing people for a coffee.
"There is also evidence that people of faith stave off isolation more than anybody else."
That doesn't necessarily have to be religion, he says, pointing to beliefs like being passionate about conservation.
"Give yourself a diverse [social circle] — and that's one thing men's sheds do, because you have everything from accountants right through to boilermakers," suggesting younger men feel welcome to join.
Mr Burrage warns social connections don't always happen organically.
"We need relationships to maintain a healthy life balance — be deliberate about creating them," he says.
Charlie Murray runs Bro Yo, a yoga class specifically for men in Canberra.
The 33-year-old developed the class when he noticed a lot of trepidation from men to join classes with women.
"Yoga is an awesome thing to do. It has a lot of physical and mental health benefits," he says.
"But also from a social aspect … the number one thing men say brings them back is the connections side of things in a non-competitive environment, unlike a lot of sports you can do like footy."
He says it also creates a "safe space for deeper conversations" about issues other than the "scoreboard".
Phone or text a friend
"Keep in regular contact with your friends, whether it's texting or phone calls ideally," Mr Burrage says.
Not relying on social media to stay connected is also important, he says.
"One of the ironic things that is happening now in society … we are connected more than ever with mobile phones and social media, but not actually meeting face to face.
"Evidence shows face-to-face relationships are the ones we need."
Michael Mann, 35, from Brisbane is married with two young boys, and says an app-based chat group has helped him and his mates stay in touch.
"It's nothing too in depth, just funny pics or videos we see.
"One of my best mates lives in Alice and we have long and in-depth text convos. It can be days between replies but it just keeps rolling on."
Interactions like this help keep friends in regular contact.
Beyondblue research showed men are less likely than women to just call their friends for a chat or to share a problem (despite 33 per cent wishing they could open up more), and doing this could help create ongoing relationships.
Diversify your relationships, even if you're coupled up
Mr Burrage says it's easy to get caught up in a romantic relationship — but that's not healthy.
"Realising when we are in relationships, with a partner, male or female, it's healthy to have other outside outlets to maintain those other relationships.
A reader Johanna Blows wrote in after reading our stories on loneliness and seconds this advice.
"To folks who are long married and interdependent, I urge you to keep up your personal interests and friendships."
Make helping others a regular gig
Becoming a part of something where you are giving back to the community in some way could help you in the long-term.
"There are so many different ways you can get involved with helping others," Mr Burrage says.
"From helping drive people to hospital, to sitting on the edge of the bed chatting to an aged care person."
Helping out with sporting groups, animal rescue shelters and art museums are some other options — just to name a few.
After all, friends are good for you
Staying connected is actually good for your health, and should be invested in, Mr Burrage says.
"There are benefits to making connections with other people — there are higher mortality rates when you're isolated, your blood pressure increases, Alzheimer's progress is more when you isolate yourself," he says.
"You're doing yourself a favour, and others, by reaching out and connecting with other people."
If you or anyone you know needs help:
• Lifeline on 13 11 14
• beyondblue on 1300 224 636
• MensLine Australia on 1300 789 978
• Suicide Call Back Service on 1300 659 467
• Kids Helpline on 1800 551 800
• Headspace on 1800 650 890
• QLife on 1800 184 527
This story was originally published on ABC Life.