Staying focused and alert throughout the day can be a bit of a challenge. Getting a good night’s rest is crucial, but so is filling up on the right foods. By now you should be looking at food as fuel, not only for your muscles but for your mind and energy stores. As soon as hunger strikes your productivity dips. This is where Keren Gilbert, M.S., R.D., founder and president of Decision Nutrition, comes in. She’s identified 10 hydrophilic (that's a fancy way of saying “water-loving”) foods to keep you full well through 5 p.m.