Most of us now realise even seemingly successful, happy people - no matter the facade they present to the world - can suffer from what former British Prime Minister Sir Winston Churchill dubbed "the black dog".
It is undoubtedly a huge step forward that depression is much more talked about than it was in the past; certainly more than during Churchill's time when the prevailing thought process was to always demonstrate (in public at least) a stiff upper lip.
Thankfully, that attitude has - and is - changing. In this country, Sir John Kirwan and other high-profile personalities have played big parts in breaking down past barriers surrounding depression and mental illness.
American comedy star Ruby Wax - a keynote speaker at the Apac Forum healthcare conference currently being held in Auckland - has spoken of her experiences after having been diagnosed with clinical depression in 1994, following the birth of her second daughter. Wax says she tried for the best part of a decade to keep the diagnosis quiet and was "mortified" when the details were first publicly revealed.
It is probably a not uncommon reaction. But, as is now recognised, it is not a healthy one. Wax says she is now happy to be a "poster girl" for mental illness and says promoting an understanding that mental health is a big issue in the world is one of her priorities.
"It used to be the bubonic plague and cholera that people had to worry about," Wax says. "But mental illness is just as pandemic. It is not something we can sweep under the carpet ... we can't change the world but we can change the way we react to it. I discuss what can be done to improve things and provide a survival guide to the 21st century."
There is a big difference, of course, between feeling "down" and suffering depression. It is not uncommon to feel sad, or even miserable. These are normal human emotions. But if such feelings persist, it is important to realise we might need assistance. It is just as important to recognise how serious depression can be. And the numbers are sobering: the www.depression.org.nz website reports one in six New Zealanders experience serious depression at some time in their lives, and that one in seven young people in New Zealand will experience a major depressive disorder before the age of 24. Women have higher rates of depression than men, and rural men have higher rates of depression than urban men.
All the experts tell us talking about our feelings is an important first step. It's important we develop relationships with people we can trust, in order that we can talk to them about our own feelings, but also so we can feel confident about asking other people about their emotions. Helplines, too, can play a big part. Whatever else is included in any 21st century survival guide, advice to speak openly and honestly will certainly be part of the mix.
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youth services: (06) 3555 906
• Youthline: 0800 376 633
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• The Word
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155
• CASPER Suicide Prevention
If it is an emergency and you feel like you or someone else is at risk, call 111.