Why Fast?

By Mark Kutolowski

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Fasting – it’s perhaps the single discipline most associated with Lent. We are reminded of the practices of prayer, fasting and almsgiving every year at the beginning of Lent as we commemorate Jesus Christ’s 40-day fast in the wilderness. While I grew up hearing about the spiritual value of fasting every year, practically this was translated into the practice of ‘giving up’ something for Lent. It could be a favored food, like chocolate or soda, or it could be giving up reading news media or watching TV. My dad always gave up eating between meals.

There’s a lot of good that comes from this common practice of giving something up. It reminds us that our desires are not necessarily the best guide for navigating life. It teaches impulse control, and if we give up something we are strongly attached to, it can be a real sacrifice. It trains us in the practice of letting go and giving up lesser goods out of the greater good of love for God.

While giving things up can be spiritually beneficial, I believe there remains a unique power in fasting in the strict sense of the term – in not eating any food for a day or more. I began doing strict fasts in college and was immediately struck by how much it shifted my spiritual awareness. It’s one of the few spiritual practices that Jesus specifically discusses in the gospels. Jesus fasted for forty days at the onset of his ministry, and later taught that certain demons could only be exorcised through prayer and fasting (Matthew 17:21). It’s the classic practice of Christian asceticism and has been used by countless saints throughout the centuries.

When we fast, we not only detach from a specific object of desire, we completely upend our habitual relationship with food. It is a simple way to turn our attention from tending to our bodies to radical dependence on God. Fasting in this way has a psychological aspect – we break from habitual patterns of mindless eating, and we learn to accept the discomfort of hunger. It has a relational aspect – we can use the sensation of hunger to cultivate compassion for the hungry of the world, and to pray in solidarity with them. It also has a profound physiological aspect – our bodies can be healed and revitalized by taking regular breaks from the work of digestion. Finally, when their energies are freed from the digestive process, many people experience an enhanced spiritual awareness and ability to pray. This is one of the reasons fasting is a widespread, nearly universal spiritual practice among countless spiritual traditions.

Fasting also supports a life of gratitude. When we are constantly fed and never experience real hunger, we can more easily forget the gift that food is in our lives. When we live on a diet of highly stimulating, processed foods, our tastes can become dulled to the marvelous flavors of simple, whole foods. When I used to guide high-end hiking trips I would eat restaurant meals several nights a week with my clients, sometimes for six weeks straight. After the guiding season ended, ordinary food seemed tasteless and unappealing. I learned that the best way to regain my appreciation for simple, wholesome food was to fast for a few days at the end of the season to reset my sense of taste.

How to Fast

To fast, simply do not eat any food or drink any caloric beverages for a period of 24 hours or more. I find a 24-hour fast is a great place to start. This fast can begin by eating a slightly earlier supper, and then resuming eating the next day with a slightly later supper so that you have been without food for 24 hours. It’s easiest on your body to do this with a lighter meal as the last meal at the start of the fast, and a lighter meal to break the fast the next day. I like to start the 24-hour fast after my evening meal because I find it harder to sleep when I’m hungry, but you can do the fast from breakfast to breakfast, or lunch to lunch as well. A 24-hour fast is easily sustainable as a weekly practice – traditionally done on Friday in remembrance of the day of Jesus’ crucifixion.

With practice, many folks are able to extend this practice to 36 or 40 hours without too much hardship. This fast involves a full day of no eating, with a final meal the night before the fast day, and the break-fast meal occurring the following morning. Longer fasts are certainly possible as well. Researchers have discovered that forty days is the typical physiological limit of how long a human body can fast without sustaining long-term damage. This parallels Jesus’ forty day fast, as well as those of Moses and Elijah in the Old Testament. Interestingly, the Greek philosopher Pythagoras also required his disciples to fast forty days before introducing them to the highest teachings of his school at Croton. It seems that multiple cultures in the ancient world understood this aspect of human physiology.

Fasting while drinking plain water is a common practice. I find a water fast goes better for my body if I add electrolytes to my water. We normally get enough electrolytes from our food and drinking only plain water without eating can upset the body’s electrolyte balance. The Slavic tradition also has a practice of dry fasting – that is, fasting without drinking water. While I don’t recommend starting with this practice, I personally find that my body often handles a dry fast more gracefully than the common ‘wet’ fast.

While you are fasting, notice your relationship with food. Are you able to experience hunger simply as a sensation in the body, or are there particular emotions and thoughts that arise with the sensation of hunger. How does it feel to not eat when you’re hungry? Whenever hunger arises, aim to turn it into fodder for prayer. You can pray for the hungry of the world who have no access to nourishing food. You can meditate on your own weakness, and your dependence on God to sustain your body and soul. You can take the time you would have taken to eat the meal you’re skipping and spend this time in prayer. You can also calculate how much money you saved by not eating, and then give this money to someone in need of food – whether directly or through a charity committed to feeding the poor.

While fasting is spiritually beneficial for everyone, there are people for whom fasting may not be physiologically appropriate. Pregnant and nursing mothers could survive a short fast but benefit more from the signal of abundance that comes with consistent meals and nutrient intake. Young children similarly benefit from abundant nutrient intake, although it’s fine for older children to experiment with short fasts if they become interested in the practice. Fasting is a positive stressor on the body, but this stressor may be too much for many elderly folks, especially if they have blood sugar issues or low muscle mass. For folks that can’t do a full fast, giving up favored foods and eating simple meals can provide many of the spiritual benefits of fasting while respecting their bodies’ needs.

If going without food is physiologically difficult for you, it may be necessary to restore your body’s ability to burn stored fat before undertaking a fast. Many people are able to do this by gradually reducing their carbohydrate intake and replacing it with dietary fat. Over time, your body will become more efficient at burning fat for fuel and will be better able to shift from burning dietary fat to burning stored body fat. When you become ‘fat adapted’ in this way, you can begin to skip meals without adverse effects. When you can comfortably skip a meal without experiencing blood sugar issues (light-headedness, shakiness, weakness, difficulty thinking), you will be ready to try a 24-hour fast.

Fasting and the Kingdom of God

Fasting trains us to recognize that even the good and necessary things of life, like food, are partial goods. As Jesus says, God alone is (ultimate) good.[1] When we restrain ourselves from eating when we’re hungry, and instead turn to prayer, we’re training our psyche to find its rest in God rather than in the satiation of our biological needs. As Jesus taught, we can’t live on ‘bread alone,’ but rather can feast on ‘every word that comes from the mouth of God.’[2] In each fast, we’re ‘seeking first the Kingdom of God.’ Fasting also provides a practical training in self-emptying that can then be applied to our relationship to more abstract aspects of our lives, like our relationship with possessions, technology, or people.

Fasting offers profound benefits, both spiritually and physiologically. However, fasting is spiritually beneficial only to the extent that we fast in humility and self-emptying. If our success in fasting becomes a source of spiritual pride, it can become destructive to our soul. As with all spiritual practice, our motivation for fasting is as important as the fast itself.

I find a weekly 24-hour or 36-hour fast is an incredibly useful discipline for changing my relationship to the thought-form of gluttony, strengthening my dependence on God, and giving myself a regularly recurring spiritual and physical ‘reset.’ If you’re able, give it a try this Lent!

[1]     Mark 10:18

[2]     Matthew 4:4