<i>Until a scientist in Australia proved ulcers were caused by bacteria. So consensus was wrong. Very wrong.</i><p>Interestingly, among people who have Helicobacter pylori in their stomachs, only a subset develops ulcers. Some people have bacteria, but no ulcer. I don&#x27;t know if there is a consensus on why this happens, but it is correlated with stress. If you are stressed and have h.pylori, you are more likely to develop an ulcer, compared to h.pylori and no stress.<p>So the consensus was wrong, but still not a hundred percent wrong.<p>Source:
Why Zebras Don&#x27;t Get Ulcers, Third Edition
<a href="http:&#x2F;&#x2F;www.amazon.com&#x2F;Zebras-Dont-Ulcers-Third-Edition&#x2F;dp&#x2F;0805073698" rel="nofollow">http:&#x2F;&#x2F;www.amazon.com&#x2F;Zebras-Dont-Ulcers-Third-Edition&#x2F;dp&#x2F;08...</a><p>Quite a fascinating book on stress.