The fat content in energy bars varies greatly, as well. When comparing the chocolate versions of many bars, saturated fat almost always accounts for more than 50 percent of the fat calories. The saturated fat comes from the palm kernel oil, cocoa butter and hydrogenated oils, which are all atherogenic, or may contribute to heart disease. In this sense, these chocolate energy bars are comparable to candy bars. Bars high in fiber, such as Clif bars and Power Bar-Harvest, are better choices because you will feel fuller longer and have a better chewing experience.
Some bars contain oatmeal, brown rice or whole grains.
The carbohydrates usually make up about 50 percent to 60 percent of the calories, as recommended. The real issue is the glycemic index of the bar. This is the effect it has on blood sugar. But those wanting sustained satiety may do better choosing bars with higher fat and protein content. Some bars are fortified with extra calcium or vitamins for a specific benefit and marketing edge.