What modern medicine’s view of fasting?

The Church considers fasting to be medicine for the soul. Modern medicine today proclaims the benefits of a vegetarian diet, and of periods of abstinence from food for the sake of the health of the body. In this way, the wisdom of the Church in linking the soul to the body is affirmed.

St. Clement of Alexandria believes that a moderate life in Christ Jesus is the royal way that leads us to heaven. Therefore, he warns us against living in luxury or squandering our money. At the same time, we should be moderate in our food, clothing, and furniture according to every person’s age, job, and health. St. Clement talks about food and drink in his book, Paedagogus ( The Instructor ) and says that we eat to live, and not live to eat.⁴⁴⁰ Our diet must be simple and aimed towards growth, health, and producing energy, though always in a controlled way. Gluttony should be avoided.

We must also not forget that love ( agape ) is practiced when having a meal together with the community, as Job did with his children (Job 1:4–5). This meal was commonly practiced in the early Church till the third century. As for drink, it is said that a little wine is good for an infirm stomach (1 Tim. 5:23), since only a small amount is taken for medical purposes.

“No one who uses [a lavish diet] will ever study to become temperate, burying as he does his mind in his belly, very like the fish called ass, which, Aristotle says, alone of all creatures has its heart in its stomach. This fish Epicharmus the comic poet calls ‘monster-paunch.’ Such are the men who believe in their belly, ‘whose God is their belly, whose glory is in their shame, who mind earthly things.’ To them the apostle predicted no good when he said, ‘whose end is destruction’ (Phil. 3:19).”⁴⁴¹

“For, quite the contrary, those who use the most frugal fare are the strongest and the healthiest, and the noblest; as domestics are healthier and stronger than their masters, and husbandmen than the proprietors; and not only more robust, but wiser, as philosophers are wiser than rich men.”[ 442]

439 St. Augustine of Hippo, Letters 36.26 (NPNF I/1:268).

440 St. Clement of Alexandria, The Instructor (Paedagogus) 2.1 (ANF 2:237).

441 St. Clement of Alexandria, The Instructor (Paedagogus) 2.1 (ANF 2:242).

442 St. Clement of Alexandria, The Instructor (Paedagogus) 2.1 (ANF 2:238).

“Some men, in truth, live that they may eat, as the irrational creatures, ‘whose life is their belly, and nothing else.’ But the Instructor enjoins us to eat that we may live. For neither is food our business, nor is pleasure our aim; but both are on account of our life here, which the Word is training up to immortality. Wherefore also there is discrimination to be employed in reference to food. And it is to be simple, truly plain, suiting precisely simple and artless children—as ministering to life, not to luxury.”⁴⁴³

“The food of those who are saved and those who perish is separate … For it were not seemly that we, after the fashion of the rich man’s son in the Gospel (Luke 15:11), should, as prodigals, abuse the Father’s gifts; but we should use them, without undue attachment to them, as having command over ourselves. For we are enjoined to reign and rule over meats, not to be slaves to them.”⁴⁴⁴

And St. Basil says, “Fasting is truly the medicine of the soul and of the body also. Eating luxurious foods afflicts us with certain difficult illnesses of the body. But fasting is beneficial for health, granting the fasting person a good complexion, calm eyes, balanced gait, and composed movements. You will never see this person cackling, although he smiles; never screaming out, although he speaks calmly and with balance; and you will find that his words flow from a clean and pure heart.”⁴⁴⁵

He also says, “What is required in fasting is not the abstinence of the mouth, but of the eyes, ears, hands, and entire body. We fast with pure hands that avoid theft, with legs that avoid forbidden places, with eyes that avoid looking upon anything that is provocative … I wonder what abstinence from meat means if we do not abstain from eating the flesh of our neighbors through gossiping and slander? And what does abstinence from food mean if we do not abstain from evil thoughts, adultery, malice, and hatred? … Fasting is the wing of prayer that raises it to heaven and breaks through to the throne of God … Fasting is the expansion of households, the mother of health, the pedagogue of youth, an adornment for seniors, a good companion on journeys … By fasting, I do not mean abstinence from necessary food, for this will lead to death. Rather, I mean abstinence from foods that cause the body to rebel. The person who fasts truly is the one who abstains from all bodily passions, even those that are natural.”⁴⁴⁶