Whilst menstruating regularly, 10 mins. B4 a bleed began, even if a period wasn't due - I would have to rush to the loo with 'the runs' - so hormones certainly upset my gut.
I was diagnosed with IBS in the late 1990s, my GP gave me
Motillium and
Colpermin capsules, to be swallowed within an hour of my main meals. Within 3 days I was feeling much better. After several years I began drinking
Actimel which kept my bowels 'regular'. It really is Trial and Error!
Your GP is not giving you good advice

. What types of cancer have your family members suffered from; did they die because of cancer or treatment? Quality of Life is important, if he/she is worried about your developing breast disease then has he/she suggested double mastectomy? Not many GPs think to discuss this side of protective treatment. Also the Research that many GPs still quote has been discounted!
I had breast disease in the 1990s, was told not to consider HRT in a vague kind of way but if I required relief from symptoms I would insist. After all, that bus might be along far earlier than cancer would develop

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Browse round. Make notes.