Doing the weekly shop can feel like a grind for many of us, especially in the mad rush to get the mince pies in before Christmas, but for some people living with the so-called invisible illnesses Crohn’s Disease and Ulcerative Colitis, it’s akin to climbing a mountain.

Last year, Sam Cleasby, 35, from Sheffield, who has a form of Inflammatory Bowel Disease (IBD) known as Ulcerative Colitis and has a permanent ostomy bag, wrote a post on her So Bad Ass blog, which went viral. She’d been criticised for using a disabled toilet whilst out shopping.

She says: “There are times when doing my weekly shop feels more like climbing Mount Everest… Yet, to look at me, you wouldn’t be able to tell that I had any extra needs.”

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It’s not surprising that Sam has welcomed supermarket Morrisons’ announcement they are changing the signage on their accessible toilets to reflect the ‘invisible nature’ of some health conditions.

From December 1 to January 30 2017, the chain is rolling out the new signs, which feature a wheelchair user and a man and woman, to 492 stores around the UK, with the tagline: ‘Not all disabilities are visible’.

The move follows a successful campaign by the patient charity Crohn’s and Colitis UK which called on supporters to email the bosses of big supermarkets, asking them to change their signs to help ensure customers with a medical condition can use toilets without fear of criticism or embarrassment.

Sam says: “To know that supermarkets are now listening to us… simply means the world. It means that the next time I am facing my Mount Everest moment, those around me might just have learnt enough to stop judging and know that sometimes there is more than meets the eye.”

10 things to know about the conditions:

1. Every 30 minutes someone in the UK is diagnosed with Crohn’s Disease or Ulcerative Colitis – chronic conditions which are the two main forms of Inflammatory Bowel Disease (IBD), causing ulceration and inflammation in the gut.

2. They are unpredictable, lifelong and potentially life-threatening conditions.

3. Crohn’s can affect any part of the digestive system and all layers of the bowel may be inflamed.

4. Ulcerative Colitis affects the rectum and colon, and only the inner lining of the colon is inflamed.

5. At least 300,000 people in the UK have been diagnosed and are suffering physically and emotionally due to these and other forms of Inflammatory Bowel Disease.

6. They’re becoming more common, especially among young people. 1 in 4 newly diagnosed people are under 16.

[Read more: What is leaky gut syndrome?]

7. The symptoms of both conditions can include diarrhoea (often with blood), severe abdominal pain, mouth ulcers, swollen joints, extreme fatigue, and dramatic weight loss. They can also cause anaemia, depression, osteoporosis and eye, skin and liver problems.

8. Celebrities who have spoken out about living with Crohn’s Disease and Ulcerative Colitis, include former TOWIE star Sam Faiers, who was diagnosed with Crohn’s Disease in 2014, and five times Olympic gold medallist Steve Redgrave, who was diagnosed with Ulcerative Colitis in 1991.

9. Possible causes of the two conditions can be genetic and an abnormal reaction of the immune system to bacteria in your gut.

10.There is currently no cure for Crohn’s and Colitis, but drugs and sometimes surgery can give long periods of relief from symptoms. One in 210 people are living with these unpredictable, life-long and potentially life-threatening conditions.

For more information, visit www.crohnsandcolitis.org.uk

Do you suffer from an inflammatory bowel disease? Tell us about it in the comments below