One of the Oldest Health Practices in Human History
read time: 6 minutesFasting might be considered a trendy “biohack” that can help burn fat, boost energy, and activate cellular repair, but it's far from a new concept. In fact, fasting is one of the oldest health practices in human history, one that's deeply rooted in Scripture and built into the rhythm of biblical life.
Before people had refrigerators, easy access to grocery stores, and endless opportunities for late-night snacking, fasting was simply a way of life.
In ancient and biblical times, unless you were wealthy, food wasn’t always available. And even when it was, it wasn’t eaten around the clock. Meals were eaten during the daylight hours, and rarely (if ever) after dark. People didn’t waste candlelight on eating after sundown, and they were typically too busy during the day to eat every two to three hours, as is often recommended today.
Grazing may be the norm today, but in ancient times, people lived differently; they ate only when food was available and long stretches without eating weren’t unusual. As you'll see below, these natural fasts brought benefits that went beyond the physical, supporting overall health and spiritual connection.
Fasting in the Bible: A Path to Health and Holiness
The Bible references fasting over 70 times, and not just for uses such as weight loss or calorie control. Fasting was recommended for spiritual clarity, breaking addictions, restoring self-control, and even opening the door to miracles.
“Is not this the fast that I choose: to loose the bonds of wickedness, to undo the straps of the yoke, to let the oppressed go free…?” —Isaiah 58:6
Fasting in Scripture was considered a physical act with spiritual consequences. It brought people closer to God, helped to heal both the body and the soul, and gave believers the strength to help others heal, too.
Jesus Himself fasted for 40 days in the wilderness. Daniel partially fasted by avoiding rich foods in order to stay pure. Esther called a national fast before risking her life to save her people. And David fasted in repentance and mourning.
What Biblical Fasting Looked Like
In biblical times, fasting wasn’t occasional. Many ancient peoples fasted regularly, such as daily, weekly, seasonally, and annually.
Some historians estimate that people fasted about 25% of the time in biblical cultures. Compare that to today, where three meals a day (plus snacks) is the norm.
Ancient cultures practiced fasting in a variety of ways, some of which are still in practice today, such as:
Daily time-restricted eating, in which you eat during the daylight hours only and fast overnight. This is similar to modern-day intermittent fasting, which often involves fasting for 8 to 16 hours daily (including overnight).
Twice-weekly fasts, such as full fasts on certain days of the week.
Seasonal fasts, which are extended fasts that were often done to prepare for spiritual events.
Sundown fasting, meaning no eating after dark, which honors the natural light cycle.
The Physical Benefits of Fasting (Backed by Modern Science)
Today, fasting often requires intentional planning, self-discipline, and a conscious decision to step away from the constant availability of food. For most of us, the goal is improved health (like weight loss). But in biblical times, fasting wasn't practiced chiefly to lose weight or optimize health. Still, better health was a natural byproduct of drawing closer to God and seeking clarity.
These natural cycles of eating and abstaining created powerful physical benefits:
People consumed fewer calories overall, which helped prevent excess weight gain.
Blood sugar and insulin levels stayed balanced more easily without constant snacking or cravings.
They maintained lean, muscular physiques with little excess body fat.
Periods of fasting likely supported cellular repair, detoxification, protection against diseases like cancer and heart disease, and promoted longevity, which are benefits modern science now confirms.
Modern research now validates what God’s people have practiced for thousands of years:
Fasting promotes weight and fat loss, often without muscle loss, as long as you stay active and regularly engage in strength training.
It improves insulin sensitivity, defends against obesity and diabetes, and supports growth hormone production.
It triggers deep cellular repair through autophagy, the body’s built-in cleanup and recycling system.
It can lift your mood, sharpen your focus, and heighten spiritual awareness.
The famous statue of David in Florence, a symbol of biblical-era vitality and strength, reminds us that obesity was rare among God’s people. When it did occur, it was often linked to idolatry, laziness, or gluttony, not the norm for a culture whose lifestyle naturally kept them active, strong, and resilient.
For ancient people, fasting was far more than a physical reset. It was a spiritual discipline, an intentional quieting of the body so the spirit could hear God more clearly. It prepared the heart for repentance, sharpened discernment, strengthened self-control, and often preceded great moments of divine intervention.
In other words, fasting nourished both body and soul, then, as it still can today.
Where to Start: Biblical Meets Modern Fasting Protocols
If you’re new to fasting or ready to get back into it, here are a few ways to begin, grounded in Scripture and supported by science:
Regularly practice time-restricted eating (also known as intermittent fasting):
Eat within a 6–10 hour window during daylight hours. For example, have your first meal around 10 a.m. and finish your last meal by 6 p.m. This approach aligns eating with your body’s natural circadian rhythm, for example, by allowing your digestive system to rest overnight. Start with a longer eating window and shorten it gradually as your body adapts.
Consider twice-weekly fasts:
Choose 1–2 days a week to skip breakfast and lunch, and break your fast at dinner. On fasting days, stay hydrated with water, herbal tea, or black coffee. Light activity like walking or stretching can help you manage hunger and keep your energy stable until your evening meal.
Try a 24-hour fast weekly/monthly:
Eat dinner one night, then don’t eat again until dinner the next night. This longer fasting period helps your body enter deeper fat-burning and autophagy modes. Plan this on a less physically demanding day. Be sure to reintroduce food with a balanced, nutrient-dense meal rather than processed or heavy foods.
Do a Daniel Fast 1–2 times per year:
The Daniel Fast is a partial fast of vegetables, fruits, seeds, and water for 10–21 days. This practice, inspired by the prophet Daniel, can be both a spiritual and physical reset. Focus on whole, unprocessed plant foods and avoid refined grains, sugars, and animal products. Spend extra time in prayer or reflection during this period to deepen the spiritual aspect of the fast.
You’ll find a full list of these fasting styles, and more tips on how to practice them, in my book Essential Fasting, which lays out detailed fasting plans to help you lose weight, feel healthier, and increase your energy, without the hassle of counting calories or planning elaborate meals.
Final Thoughts on Biblical Fasting
Fasting isn’t just another health trend but a time-honored holy invitation. It can help reconnect your body to its original design, get you back in touch with your hunger and fullness cues, help you manage cravings and overindulgence, and renew your mind.
Perhaps even more importantly, fasting draws your spirit closer to the One who created you.
If you’re ready to experience a breakthrough in your health, emotions, and spirit, consider doing less rather than more: cut out modern-day processed foods, go without food for longer stretches, and let your body and soul rest. As you simplify the types of foods you eat and how often, you create space for clarity, strength, and renewal.
References:
https://nutritionsource.hsph.harvard.edu/healthy-weight/diet-reviews/intermittent-fasting/
https://pmc.ncbi.nlm.nih.gov/articles/PMC4516560/
https://bhma.org/fasting-a-modern-take-on-an-ancient-practice/
https://www.eurekaselect.com/article/136295
https://pmc.ncbi.nlm.nih.gov/articles/PMC8754590/