The “hangry” meme is real. If you don’t eat for a while, you are more susceptible to the negative states of anger and irritation than if you were sated. This poses a problem for Orthodox Christians, who fast from animal products for about half the calendar year, not only abstaining from certain types of food but also reducing overall portion sizes. How can we perform the fast without falling into grumpiness that may open the door to passionate sins?

Can anyone think that where there is no prayer and fasting, the devil is already there? One can! —Saint Theophan the Recluse


Anyone who rejects the effort of prayer and fasting is capable of doing nothing but evil—and all his apparent good, if he has any, is in truth not good at all, but also evil; because according to Christ’s words: “A corrupt tree cannot bring forth good fruit”: “do men gather grapes from thorns or figs from thistles?” (Matt. 7:18,16). “Beware,” Christ therefore says, “of false prophets which come to you in sheep’s clothing, but inwardly they are ravening wolves” (Matt. 7:15). —Archbishop Averky

The key to understanding your mood in a state of hunger is blood glucose. After you eat a meal that contains glucose, which is found in sugars and carbohydrates, your body shuttles that glucose to your muscles and brain, where it is used as an immediate and accessible energy source. For the glucose that is not immediately utilized, your body converts it to glycogen. As an analogy, we can liken glycogen to glucose stored in a closed bottle and put on the shelf (it’s actually multiple glucose molecules chained together).

Depending on your unique physiology, your blood glucose concentration will dip 2-3 hours after eating. Your brain and muscles continually need glucose, so through a complex mechanism called glycogenolysis, the “bottle of glucose” (glycogen) is retrieved from the shelf and opened to release the amount of glucose that is needed for you to function normally.

The amount of glycogen stored in your body is not unlimited: you have about 2,000 calories worth stored in your muscles and liver. If you’re an athlete and hit the “wall” during intense activity, unable to perform further, you have used up all of your glycogen (and free glucose). You have run out of gas, so to speak, but you do not need to be an athlete to run out of preferred energy stores. It is estimated that a sedentary person who is fasting from food will extinguish all their glycogen in 12-22 hours, and that will depend on their muscular physique, metabolism, and general level of activity.

If you run out of glycogen and do not have an immediate food source, do you soon die? No, our all-wise God has implanted an exceedingly complex mechanism in the animal world called gluconeogenesis which converts fat into glucose. What’s amazing about the gluconeogenesis pathway is that fats contain no glucose molecules at all, but God has easily found a way to make the chemistry work. Gluconeogenesis will occur during prolonged exercise and fasting, or if you’re eating a low-carb diet. There’s only one major issue with gluconeogenesis: it’s slow.

Your body can convert glycogen to glucose pretty fast, but converting fats to glucose takes more time and happens in a stepwise fashion like a home thermostat slowly arriving at a set temperature. Therefore, if you’re all out of glycogen, you will enter a state where your body does not have a preferred energy source. During that time, you will begin to feel the classic symptoms of fatigue, mood irritation (i.e. “hangry”), bodily weakness, and even pain in the form of headaches.

When I’m hungry, and have not eaten for over 12 hours, I often enter a state of irritation. I’m much more likely to complain and snap at those who are close to me for the most trivial of reasons. I’ve since learned to not talk at all when I’m hungry, at risk of saying something I regret. Spiritually, I was told by a monk that not eating reveals the naked state of your being when it’s not being sated with food or some other pleasure. I have a history of anger and irritation, so when I’m not being fed, those problems are able to directly rise to the surface. Modern scientists theorize (i.e. guess) that glucose is needed to control the willpower centers of the brain. When your brain doesn’t have glucose, they say, it shuts down the willpower to be a decent human being.

I would have believed the biological theory if I wasn’t an Orthodox Christian, where states of grace can transcend the body’s immediate biological needs. This year, I went to a monastery for the first week of Lent. For several days in a row, I was able to eat the one served meal a day, something I had never done before, and experienced no irritation or anger. I didn’t even feel weak. The reason is I was attending several hours a day of services. My soul was able to use any grace received from the services to supplant my body’s need for food, but then the grace ended and I could not stop thinking of food. I again felt the desire to eat multiple times a day along with sharp periods of irritation.

There is certainly a biological reality, for we do exist in the body, but it does not supplant the spiritual reality of grace that God gives to our soul at His discretion. An Orthodox Christian only needs to read the lives of the saints to see countless examples of men eating only bread and salt for prolonged periods. It’s not that these saints were anatomical supermen like professional athletes, but they so pleased God that their faith was able to suspend biological laws by grace for a sustained period.

When I’m at home and only attending one or two divine services a week, I don’t have much in the way fasting grace, and every day is a struggle. I’m tempted to eat three meals a day or else I’m grumpy and can’t take my mind off food. From these struggles, here are five things I’ve learned on my quest to fast better…

1. If I’m getting angry and cannot control my thoughts or speech, it’s better to eat. Our faith is a faith of love, so if you’re a heroic faster but you’re having angry thoughts or actually attacking those close to you, you may be missing the point of the fast.

2. It takes about 30-120 minutes for your mood to be restored after eating. The bigger the meal you eat, the longer it will take for your body to digest the glucose. For an acute attack, you can try eating a couple tablespoons of honey with a slice of bread for faster relief.

3. It’s easier to fast for yourself than to fast for God. Before I came to Christ, I often did intermittent fasting and regularly went for 18 hours without eating. The reason I fasted was to improve my appearance to aid in achieving sin with women. Satan helped me every step of the way, and I did not notice being grumpy or having angry thoughts, probably because I liked my passions and thought it was an irrevocable part of my identity. To do the Orthodox fast is significantly harder because there is no worldly gain from it and the standard of Christian love is quite high.

4. Moderate bodybuilding can make you ravenously hungry. If I don’t do any workouts, and sit in front of my computer all day, I can eat two medium-sized meals without too many tears, but if I just do a little callisthenic training, I become rather hungry on the day of the exercise and the day after, and when I do eat, I have to fight the temptation to eat big. For fasting periods like Lent, you may want to tone down your workouts so that your fasting is not unnecessary hard.

5. Don’t immediately run to the pantry upon the first hunger pain. You won’t starve, though you may be tempted to believe so. I wait an hour for the sharp hunger pain to morph more into a dull ache.

This is the mark of Christianity: however much a man toils and however many righteous acts he performs; he must feel that he has done nothing. In fasting he must say, “This is not fasting,” and in praying, “I have not prayed,” and in perseverance at prayer, “I have shown no perseverance; I am only just beginning to practice asceticism and to take pains.” And even if he is righteous before God, he should say, “I am not righteous, not I; I do not struggle, but barely make a beginning each day.” —Saint Makarios of Egypt in The Fifty Spiritual Homilies

I’m a mediocre faster at best. I can abide by the dietary restrictions without much anguish, but I still eat a good amount and do not always lose weight during prolonged fasts. In times of grace where my prayer is strong and I’m attending daily services, I can fast harder, but while at home I am able to only do the bare minimum. Thankfully, God does grade us based on effort and struggle instead of pounds lost. With the knowledge of how my body works, and the fact that fasting separates me from the world to draw nearer to God, I continue to fast, and hope that my fasting becomes stronger in the years to come.

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