I was eyeing bottles of Ensure at the grocery the other day...don't even need to be refrigerated, tiny bottles, quick to drink, vanilla one tastes pretty good...I was drinking them once when I had a health crisis and couldn't eat a lot and they helped me feel much better. I think I'll send some with the husband when he's pretending to fast for his mother when she's here.
The key to surviving Ramadan is water. Water, water, water. Like, insane amounts of it. A gallon in the morning, several through out the night, and more when you break the fast. A lot of the fatigue people feel is not as much about the hunger, but the onset of dehydration. If you don't obsessively make up for the lack of water during the day, you'll suffer.
And yep, Ensure works wonders!