When the sun rises on Sunday, March 2, Baha’is throughout the world will have taken their last bite of breakfast and their last sip of water for the day.

Until they break the fast at sunset, they’ll try to block out hunger pangs, lightheadedness, cottonmouth, the lovely scent of food wafting from the restaurant down the street.

This test of willpower continues through March 20, when the Baha'i Faith’s annual Fast ends, to be followed the next day by Naw-Ruz, the Baha'i New Year.

Like fasts in other religions, the Baha'i Fast is a time for members of the Faith to reflect on individual spiritual progress, try to detach from material desires and “make an effort to know God better,” as one Baha'i put it.

In addition to fasting, Baha’is say special prayers before meals, such as “These are, O my Lord, the days in which Thou hast bidden Thy servants to observe the fast. Blessed is he that observeth the fast wholly for Thy sake and with absolute detachment from all things except Thee.”

Fasters also turn after-sunset meals into festive occasions shared with friends and family. What they eat varies greatly.

“Don’t eat sausage, because it makes you thirsty later in the day,” advises one young Baha'i. “Drink something warm or have soup before dinner,” recommends another. Some fasters down a breakfast large enough to qualify as all three meals. Others eat lightly, claiming it stabilizes their metabolism. Still others derive their stamina not from the cuisine but the company.

“Some of my best memories . . .are from the devotional (prayer) gatherings held at dawn,” one Baha'i says. “It gives you such joy and energy.”

Baha’is who can’t literally gather round can do so virtually with the advent of the Internet. Websites, forums, blogs and email all serve as support systems to fasters round the world.

In addition to tips and suggestions, one site injects a little humor: “Visit your local Jenny Craig and shout: ‘Hey everybody, I'm saving 400 bucks.’" Another site helps fasters figure out sunrise and sunset times by location.

Perhaps the most practical support a Baha'i faster can get is to hang out with other Baha’is.

“Being at the Baha'i National Center makes it much easier to fast than other places I’ve worked,” says Linda Seabloom, who works in the Education office. “Co-workers elsewhere always try to offer you something. They think a little enticement won’t matter. But here everyone is trying to observe the Fast, which unites you even though it is an individual practice.”

The rest of the year, Ms. Seabloom says, “We’re reminded of our dependence on the physical world, but aren’t always are reminded to rely on God. The Fast allows us to honor our relationship with Him and make sacrifices. And, in turn, He ensures that our needs our met.”