Some religious diets are perpetual, like "no pork ever". Orthodox fasting is "eat everything half of the year" and then practice self control by abstaining from the meat/wine/oil/dairy the other half.
"I think atheists actually empathize with the poor even more"
I think both this statement and the one you are responding to are getting to general/stereotypical. Fasting can be some meaningless ego/status religious thing. Just as some atheists might be more empathetic.
In my limited experience, the religious fasters seem mostly to be doing it because their community (church) does it and they want to belong, not for the exercise in self control or empathy. Although i msure both exist. It's also been my experience that atheists aren't any more empathetic towards the poor than the average person, religious or not.
It's hard to be in prayer all day. If you're hungry however, you are perpetually reminded and thinking of God.
You are not supposed to go hungry, just be strict on what you consume.
Most lay orthodox christians only "truly" fast before taking communion and around a few particularly important holidays. So when they talk about fasting they are not normally talking about something that resembles intermittent fasting in practice.
It is a opportunity to emphasize with those in poverty. It is a way to truly appreciate every meal - saying grace before a meal take on a real significance. And it is an opportunity to be truly thoughtful about the food you are putting into your body - particularly as the fasts are often "no meat" or something else specific.
She is also not surprisingly a very good cook and cooks most things from scratch. If she were to start a food company, I'm sure she'd use the same values.