As we stagger through the dog days of August and into September, more than a billion people will rise each day to fast. This year's lunar calendar brings the warmest Ramadan in recent memory, its arrival accompanied by a trifecta of oppressive heat, back-to-school "spirit," and the tremors of economic crisis.

From daybreak to sunset, neither food nor water will pass the lips of the fasting person. As a teen, I often had to be reminded to slow down during dinner, or iftar, when I was prone to voracious acts of gluttony, after which I'd be listless for the remainder of the evening.

But what I loved most was suhoor, the pre-dawn meal meant to keep us hydrated and focused for the day. At 4 a.m., my mother would gently rouse us. We'd sit squinting and disoriented on the floor around a coffee table, taking mechanical bites of leftover pasta and toast, until the imam's prayer at dawn, signaling the commencement of the fast.

During Ramadan, Muslims are expected to make a greater effort to embody a better version of themselves, and this usually includes a movement toward conscientious detachment from material luxuries. Properly observing the fast is supposed to induce a calm and comfortable feeling through generosity, sacrifice and compassion.

Some people also are inspired to overcompensate for one perceived extreme with another, and Ramadan also can be a time for rewarding asceticism with overindulgence. You know the New Year's general formula of resolutions and refrain after a holiday season of excess? What I used to experience after Ramadan was something very similar.

Fasting as a form of physical and spiritual cleansing has been practiced since the dawn of religion. Forms of the fast are mentioned in the Bible, the Mahabharata, the Upanishads, both the Old and New Testaments, and of course the Quran. Many Western Christians fast during Lent and Eastern Christians for Great Lent, Bahá'ís fast during the month of Ala, and many Jews fast on Yom Kippur and Tisha B'Av.

Eating in public during Ramadan is strictly forbidden. Twenty years ago, outside a public park, I saw a municipal gardener, ashen and weaving through a row of date palms. He stooped and tried to drink from a hose of running water, his eyes darting to and fro as he slurped. Beneath his gray robe, his shoulders quaked.

Some people are simply unable or unwilling to fast, and legions of people who feel unwell while fasting have no understanding of why this is so. Possibilities include diabetes, hypoglycemia, electrolyte imbalance or latent heart conditions exacerbated by dehydration. By definition, fasting is the voluntary abstinence from some or all food and drink for a period of time, and though it can be enormously rewarding, it needs to be performed with care.

Though it's intended as a form of rejuvenation for mind, body and spirit, fasting also can be draining, and is not expected of children or anyone in fragile health. During Ramadan, markets, workplaces and schools in many Muslim countries modify their hours so that people don't overexert themselves.

I remember shortened lunch hours from my school days. Non-Muslim students were scurried off to an annex where they could eat in privacy and haste. It seemed inevitable that once or twice a week, a fasting child would pass out in the midday sun and be dragged off to the nurse's station for a glass of water and a cold compress. However, a properly held fast is meant to instill a sense of inner peace rather than instability or irritability, so taxing activities are generally discouraged.

Many people I've met in Santa Fe are fond of popular regimes like Stanley Burroughs' Master Cleanse, juice fasts, raw-food fasts and Panchakarma, an Ayurvedic set of procedures that are believed to purify the body. Though the motivations vary, the practice is wrought of the same hopeful resolve, especially for a born hedonist like me who has trouble being hungry for very long. But with so many people in the world going hungry every day, it behooves us all to remember what real appetite feels like — and to never take it for granted.

Nouf Al-Qasimi is a freelance writer living in Santa Fe. Send e-mails to food@q.com.