I divide food into 3 categories:
(1) Things that could give you listeria
(2) Things that could give you toxomoplasis
(3) Things that could give you salmonella
(1) is the most important b/c it can cause miscarriage, but also the hardest to police as so listeria outbreaks can arise from all sorts of random foods, so I just go for the obvious triggers: shellfish, unpasteurised cheese (impossible to get hold of where I live), Mr Whippy.
(2) is also important as could cause brith defects so I avoid rare meat and also cleaning out the cat's litter box actually I suspect I have toxo immunity as have always had a cat but it suits me to make DH do it
(3) is less risky to the baby but could be unpleasant and slightly risky, so I just take care not to eat dodgy food which might cause food poisoning (which I would do anyway). This is why I continue to eat sushi and hummus from safe sources, for example. I'm not that worried about eggs as I think the salmonella risk is v low.
Alcohol and caffeine don't fall into any of the three categories, but I think are fine in moderation (moderation for pregnant woman, not what I would've considered to be "moderation" pre-pregnancy!!
).