While not an official claim, Meiji studies indicate that in test subjects users burn fat earlier in the exhaustion cycle, providing more energy early and avoiding the abrupt switch from burning carbohydrates to burning fat. Combine this with the fact that you get more energy from fat per gram (7 kcal vs 4 kcal from sugar) and the fact that you have more fat available and this graphic claims that VAAM makes 80,000 kcal of energy more readily available than the usual 2,000 kcal from sugar.
Interesting to see how marketing people handle study results. 明治 ヴァーム
Photo is a web capture for explanatory purposes, copyright belongs to the company.