It was needing to have her large intestine removed that inspired Nicola Dames to start her own underwear business.
As the former intensive care nurse adjusted to life with a colostomy bag 10 years ago, one of the things that upset her was no longer being able to fit into the fashionable underwear she loved.
"I could always see my bag sticking through at the top or bottom," says Ms Dames, now 39.
"[Then] I realised the problem wasn't me, it was the underwear."
Annoyed by the lack of decent underwear for women in her position, she decided to create her own - fashionable, but with a pouch to carry a colostomy bag. And so her business Vanilla Blush was born in 2008.
To get the company up and running from their kitchen table, Ms Dames and her husband Simon remortgaged their Glasgow flat to raise £11,000, and started selling 12 products for women.
Today, they sell more than 200 garments for both men and women, ranging from underwear to swimming costumes and sportswear.
In addition to a shop in Glasgow's East End, orders come from around the world via Vanilla Blush's website, and the business is on target to start turning over more than £1m a year.
"We've come a long way," says Ms Dames.
While Ms Dames' story is certainly inspirational, she is actually just one of numerous entrepreneurs around the world who have been inspired to set up successful businesses following a brush with serious illness.
New Yorker Jon Loew, 44, was facing death when he came up with his idea for KeepTree, an online system that allows users to capture, securely store, and schedule video messages for release in the future.
A bad reaction to an antibiotic meant that, within a month, he went from a healthy dad to his body gradually shutting down. Doctors were puzzled, and Mr Loew was contemplating his imminent demise.
With children of eight and five at the time, he was worried that they would grow up with few memories of him.
Mr Loew says: "I'd be this guy that they vaguely remembered, so I started recording videos... and labelling them with the dates when I wanted my wife to give them to our children, because I wanted the videos to be appropriate with things going on in their lives."
When doctors got his condition under control, the idea of using videos as a means of communicating from beyond the grave stuck.
On a 2011 business trip for his TV company, Mr Loew mentioned it to his now co-founder Hiroshi Nakata, who raised a few hundred thousand dollars overnight.
KeepTree has now raised more than $5m (£3.5m) from investors and has offices in New York and Tokyo.
It's a profitable business and it isn't just used by people who are terminally ill. Instead, users do everything from recording a birthday wish to be delivered in a month's time, or filming a bedtime story for your children while you are away with work, or sending a video of a singing grandchild to proud grandparents.
KeepTree has also indentified new areas for growth and recently launched Vift, a video gift messaging service for online retailers.
If you are buying a gift for someone from a shop that uses Vift you can also record a video. And when the physical gift is delivered to the recipient the video is then emailed out.
Mr Loew says: "It's a way of personalising an online gift. Once the courier delivers the gift, that triggers the video to be delivered."
For Anikka Burton, it was having breast cancer nearly five years ago that prompted business inspiration.
She began her online gift business Not Another Bunch of Flowers in 2013 when she realised there was a gap in the market for get-well presents specific to people with cancer.
"Flowers are banned from hospitals because of the infection risk, so I returned home to find a lot of dead flowers," says the 38-year-old, who is based in Sussex, in southern England.
"It was quite depressing, yet flowers are the go-to option."
After her treatment ended Ms Burton spoke to suppliers, began going to trade shows and decided to invest an initial £5,000 in products that she had found helpful or would choose herself.
"I lost my mum to breast cancer, so I have an understanding of what it's like to be the loved one as well as the patient," she says.
"But I was cautious at first. It took about £15,000 to start up, but I put a small amount in at the start; and as I had more confidence in the business, I released more money."
Her website now sells 530 gifts, ranging from get-well cards, to hampers and toiletry products free from chemicals that people with cancer are told to avoid.
Ms Burton says her business broke even in its first year and for 2016 she expects to see its turnover top £330,000.
Selling cups of coffee has been the route to recovery from anorexia for 30-year-old Canadian Lindsay Brock.
Her eating disorder had been so debilitating that she had been forced to give up her work managing coffee and tea shops.
When a long-awaited treatment programme in Toronto didn't work, she says she began to have thoughts of suicide and decided that she needed something other than her illness as a focus.
So she decided to fulfil her lifelong dream and open her own coffee shop.
Amuse Coffee Co, a Parisian-style cafe in the Ontario city of Peterborough, opened its doors in August 2015, and Ms Brock runs it with her husband and two part-time employees.
Although Ms Brock has to be careful not to overdo things for the sake of her health, the business is on target to turnover 135,000 Canadian dollars ($104,000; £72,000) in its first year.
She says: "My mantra right now is 'do less with more focus'. Baby steps."