Bars can be a lifesaver on busy days, and these Core Organic Overnight Oat Bars ($48 for a pack of 16) are one of the healthier options on the market. They're made with ingredients like whole-grain oats, peanuts, and chia seeds. Plus, each bar contains prebiotics and live probiotics to support gut health. Those probiotics may just help with your weight, too. In one study, a supplement containing the probiotic found in these bars, along with other strains of good bacteria, helped reduce body weight in those who were overweight.