I work an office job and eat 5-6 times per day. Because the foods I eat are low fat, high protein, with an adequate amount of fiber, I don't deel weighed down. In fact, I feel great. Here's the "at work" consumption:
(1) 7:00 a.m., protein shake (during drive to work): cal: 120, fat: 2, prot: 20, carbs: 4; 3 fish oil capsules 30 cal. 3g fat
(2) 9:30 a.m., meal replacement: cal: 120, fat 1.5, prot: 15.0, carb: 10.0, fiber 0.5
(3) 11:30 a.m. brewers yeast: cal. 120, fat: 0.0, protein 16.0, carb: 13.0, fiber 6.0; lecithen, 1 tb cal: 40, fat: 4.0, carn .05
(4) 1:30 tuna: cal. 150, fat 1.5, protein 30; whole wheat tortilla, cal. 80, fat: 3.0, prot: 8.0, car. 19, fiber 14
(5) 3:30 repeat meal 4
(6) optional, repeat meal 1 on lifting days
also drink 1.0 gal of water at work
SUMMARY (1-5 TOTALS):
CALS: 870
FAT: 19.5
PROT: 127.0
CARB: 65.0
FIBER 34.5
There's no magic to the above formulla. It's identifying what you think you need nutritionally, then finding the combination of foods and supplements to get you there.