Upvote:5
A quick Google search for "terrorist activity during ramadan" shows that nowadays Ramadan isn't making Muslim places safer.
On the other hand, I would advise against going to Muslim countries during Ramadan, unless you're Muslim yourself. Activity level is generally lower, many places are closed - including not just bars and nightclubs, but even some swimming pools - and there are other restrictions, which depend on the country. Thus you might have issues trying to follow your regular schedule - such as eating or drinking water during the day.