Although I've never fasted on days other than Ash Wednesday and Good Friday, I'm considering adding in one fast day per week this Lent; Anastasia makes a compelling argument that fasting is a different discipline than just "giving up" something for six weeks, since the point of Lent isn't merely to sacrifice a few pleasures or to find a little more time to attend to the spiritual.
As she writes:
It's about finitude. It's about death. It's about the limits of a body that is dying. There's nothing that makes a person aware of her limits like fasting. And on top of that, fasting exposes the deficiencies of character that exist when one is stripped of ordinary comforts. It's about stark naked mortality. And unless you need the internet or chocolate to live. . . then you aren't getting it.
This is what I feel, too, when I fast (even in the very modest ways that I do fast): my deficiencies of character. Fasting makes me tired and cranky and low-energy, and that means it's more of an effort to be patient with and pleasant to the people I encounter. However, since fasting is something totally within my control, and since I'm very aware of why I have a shorter fuse, it's easier to be courteous than on days when I've accidentally skipped meals. Ideally this makes me more mindful, on other occasions, of what others deserve from me no matter what my mood, my preoccupations, or my state of health.
But there are problems with fasting, too. Anastasia talks about the misuses that fasting can be put to by those with eating disorders or who otherwise find pleasure in pain, but for most of us the temptation is simply toward satisfaction with our own virtue. We live in a culture that easily converts any form of self-discipline into a commodity, a challenge, or a sign of personal merit: take this 14-day juice fast and feel extra-specially virtuous! know your superiority to those who merely eat sensibly and go to the gym! you, my friend, are winning the self-improvement sweepstakes!
And that's what's hard about Lent, in the end: making it about one's limits while not making it about oneself.