This new version of Glutathione Force is "pro-liposomal", which means it is designed to provide the body with the building blocks necessary for packaging the glutathione into liposomes (little sacs or spheres, basically) during the process of digestion. Digestion is triggered by the act of eating or the presence of food already in the stomach. Supplements in general are properly thought of as food supplements. Taking them on an empty stomach can cause issues purely stemming from insufficient digestion.
With this new formula, the important thing is to just keep at it: your glutathione levels will gradually increase over time (months). That's what you want, not a quick rise and drop within a single day. So, take with or without food, but preferably with food or after a meal, and take it consistently for best results.