Hunger is a product of a lack of food, and particularly a lack of nutritious and filling food. Chronic hunger is often linked to malnutrition, largely because the body just isn't getting adequate nutrition nor are the few calories its getting high quality ones. Most people who experience chronic hunger because they don't get enough food are not doing this willfully. However, "fasting" is different. This is the purposeful abstention from food, and sometimes drink, for any number of purposes.
Why am I bringing up fasting, when the whole point is to eat on a $1.50 per day and not avoid food entirely? Yesterday a coworker raised the topic of my "fast". When I tried to correct him, noting that I am in fact eating, he argued that I am on a fast in the broader sense of the word. By not consuming in my usual way, by abstaining from higher cost foods, in a way I am fasting.
The act of fasting seems to surface on many occasions - for religious reasons (e.g. the Day of Atonement in Judaism), to make a political statement (e.g. Ghandi's hunger strike), or perhaps as a form of bodily 'cleanse'. But regardless of the reasoning, I think the abstention from a normal practice promotes thinking in a slightly different way. You suddenly have to think more about what you put in your body, have to critically assess why it is you are even doing this. Seeing as one of the motives for the Live Below the Line challenge is to foster empathy and discussion around a particularly tough issue, 'fasting' in this broader sense of the term is really rather appropriate for the physical and mental challenge that takes place.
Thanks for indulging. Happy May Day!