She says: "For years I have been battling recurring constipation, abdominal pain and bloating. Go ahead and laugh. We laugh because we're embarrassed. In order for us to get relief, we have to talk about our symptoms and stop suffering in silence.
"I have tried nearly everything: changing my diet and watching what I ate. I exercised regularly. I even tried taking fiber supplements and over-the-counter laxatives, but nothing helped with all of my symptoms.
And good for her! I think that many IBS sufferers will identify with what she says: from embarrassing, unmentionable symptoms to doctors who insist that our bowel problems are really in our heads.
We may identify less with her relief from one drug alone (although the new drugs Zelnorm and Lotronex have had a good success rate in America), but we could all benefit from talking more openly with our doctors and looking for more solutions rather than accepting that IBS will rule our lives.
What Cybill Shepherd has done, though, is more than just draw attention to the fact that IBS sufferers need more help. Just by revealing that she is an IBS sufferer she has shown that IBS can affect anyone. Here is a glamorous, successful actress, someone who has kissed Bruce Willis and won three Golden Globes, saying that she has trouble with her bowels.
The power of celebrity
In these celebrity-soaked times it can be easy to forget that famous people sometimes achieve genuinely selfless and compassionate things just by using their fame. The greatest power that they have is the ability to shine the light of their stardom on an issue which would otherwise have been ignored.
And yes, the issue may sometimes be whatever cause is most fashionable at the time - "Gay whales against racism" as one satirist put it - or the one which helps the star more than the people (or whales) who are suffering. But sometimes there is no doubt that the celeb has really stuck their neck out to help others who are dealing with an issue that is considered untouchable.
And I can't thing of a more untouchable issue than IBS, something that no-one in the public eye would readily admit to. Can you imagine Julia Roberts standing up and saying "Diarrhea is the blight of my life and hemorrhoids have driven me to drink"? No, of course not, because anything remotely digestive is considered highly embarrassing and distinctly unglamorous. Cybill Shepherd's admission, therefore, is to be applauded.
Dare not speak its name
Before Cybill Shepherd 'came out', the only famous person I knew of who had IBS was Kelsey Grammar's wife (Kelsey Grammar used to play Frasier in the eponymous sitcom and Cheers).Whoever you are, whatever your gender or problems or pain, it is vital that you find someone with whom you can identify. If you watch TV and never see a reflection of yourself, if you are a black man and only ever see white faces on screen, then you will start to feel alienated - and the same goes for people who are ill.
If you constantly hear about diabetes sufferers and asthma sufferers but never hear a word about bowels then you begin to learn that your illness is far less important than these other worthy causes.
We need more people in the public eye standing up and saying "Me too", so that everyone can start to realise just how widespread a problem this is.
Don't suffer in silence
But it's not just about how other people perceive us, and how we perceive ourselves. It's also about making sure that anyone who has bowel symptoms seeks help, and at the moment that just doesn't happen.
There are still many people with bowel problems who are too ashamed or embarrassed to go to the doctor, and just soldier on through their lives when they could be receiving treatment. And there's always the risk, of course, that their symptoms could actually be the result of something other than IBS that may get progressively worse if it is left alone.
IBS often goes undiagnosed for years, and even when we pluck up the courage to visit the doctor we can be so tongue-tied that we don't properly describe our symptoms. If we could leave our embarrassment in the waiting room it would be so much better for our health.
And things can change. Just think about breast cancer, which is now regularly discussed on TV and radio, but 20 years ago was stuck behind a wall of silence where breasts were not to be mentioned, cancerous or not.
If we can just get a few more Cybill Shepherds to speak out for IBS then the celebrities of this world might start wearing ribbons for you and me, and leave the gay whales to fight for themselves.