Hi,

As a native of Istanbul I can assure you that you won't have trouble locating open restaurants during the day during Ramadan. The area around the PH is upscale and "westernized" so you'll have absolutely no trouble. Same for the GH, although I would suggest that you choose the PH as it's a more interesting area with far more dining venues and choices. Only in fairly conservative neighborhoods would you run into issues finding food during the day, and it's not likely that you'll venture into those areas. Hope this helps and feel free to ask follow-up questions.