Brain feeling sluggish Grab a Clif Bar Builders Protein Bar out of your 12-pack, and pep up. Each of these bars contain a whopping 20 grams of protein, along with vitamins and minerals, to give you a boost when start to zone out rather than be in the zone. Clif Bar doesn't use trans fats, and this low glycemic bar won't cause a sugar high followed by the crash and burn.