Most Helpful Guy
General rule is if it doesn't explicitly say so, it isn't. In the UK, it should say wholegrain (or wholebran). Even if it does say that, most 'wholegrain' bread isn't more than 60% so. But be wary of grains that claim to be wholegrain, then you look on the back of the packet, and it says 11% wholegrain. Blatant false marketing. Other thing to look out for, is the less ingredients, the better. You can get bread that is 100% wholegrain, sourdough (uses natural leveners, yeast free), and not fortified with vitamins and minerals (I mean, the question must be begged why food should need fortification anyway); however, most people wouldn't be able to bear the taste. The cost can be prohibitive too. Most wholegrain bread seems to be a half way house in terms of goodness. Ideally, of course, one would create their own bread using homemade sourdough, this would once again instill bread's vitality! But alas, this is pretty impractical for most people with jobs.
But yeah, basically, the packet should state it somewhere. If it doesn't, then you can assume it's not.1
Most Helpful Girl
It needs to have "whole wheat flour" listed as the top ingredient.