..from the fourth chapter of the Mishnah Torah – on Wisdom (Hilchos Da’os).

Editor’s Note. In this chapter from Hilchos Da’os from the Mishneh Torah (chapter four), the Rambam offers principled advice on maintaining and gaining health, both from traditional Jewish sources and from the medical literature and philosophy. The source of this guidance about the health qualities of certain particular foods has likewise been the subject of classic debate. Nonetheless, as a tradition of faith, his advice in these matters too, has always been considered extremely worthwhile and of the most significant spiritual foundations.
Halacha 1. Behold, that the body is maintained in good health is of the ways of the Lord, for it is impossible to understand or to have knowledge of the Creator if not well. Therefore, one should keep away from things which weaken the body, and accustom oneself to healthy and soothing customs, which are as follows: One should never eat unless hungry, nor drink unless thirsty, nor should one hold back for even a single moment from relieving oneself. Whenever one feels the need to pass water or to defecate, one should tend to this immediately.

Halacha 2. One should not eat until one’s stomach is entirely full, but only until about a quarter of the way from full. Nor should one drink water during a meal, except a little mixed with wine, but once the food begins to digest one can take what one needs to drink, but one should never drink too much, even when the food digests. One should not eat unless one has checked oneself to make sure that one does not need to relieve oneself. One should also not eat until one has first walked to the point that the body has warmed, or if having involved oneself with another envigorating or strenuous activity. The general rule of the matter is that one should always respond to one’s body. In the morning, one should do activity until one’s body gets warm, then one should wait until the body has cooled down somewhat, and then eat. All the better if one bathes in hot water after the exertion, and afterward also delaying a short while, and then partaking.

Halacha 3. When one eats, one should always sit in one’s place, or recline on the left side, and one should not ride, work or agitate one’s body until the food has been digested. Someone who goes for a long walk, or exerts himself at work after eating will bring upon himself bad and difficult illnesses.

Halacha 4. The day and night combined are twenty-four hours long. It is sufficient to sleep for a third of this, which are eight hours. This time should be toward the end of the night, so that there are eight hours from when one goes to sleep until sunrise, and one should arise before sunrise.

Halacha 5. One should not sleep face down, nor straight upward on the back, but on one’s side–at the beginning of the night one should sleep on the left side, and at the end of the night on one’s right side. One should not sleep soon after having eaten, but should rather wait afterward about three or four hours. One should not retire to sleep during the day.

Halacha 6. Foods which excite one’s bowels; such as grapes, figs, berries, pears, melons, or particular types of cucumbers or squashes, should be eaten with the first arousal of the appetite–before the meal. One should not mix these with the meal’s other foods, but should wait until they have descended from the upper stomach. Foods constricting to the bowels, such as pomegranates, quinces, apples or Crustumenian pears [an ancient grafted variety, small and acidy] should rather be eaten at the end of a meal; nor one should one eat too many of this grouping.

Halacha 7. If one wants to eat poultry and animal meat together at the same meal, one should partake of the poultry first. If one considered to eat poultry and eggs together, one should eat the eggs first. If one wanted to eat meat of a small animal and meat of a larger animal together, one should eat the meat of the smaller animal first. One should always eat the lighter foods before the heavier foods.

Halacha 8. In summer, one should eat bland foods without excessive amounts of spices, and one should also have vinegar. In the winter, one should eat invigorating foods and with more spices, and even add small quantities of mustard and asafoetida [a popular Mideastern root condiment and digestant]. One should adopt this rule both in colder climates and in hotter climates, and generally in all situations where there is sufficient seasonability to apply it.

Halacha 9. There are some foods that are exceedingly bad, and it is fitting never to eat them. Such foods include large fish that are salted and old, old salted cheese, truffles and mushrooms, old salted meat, wine straight from the winepress, and cooked food that has become odorous. Similarly, any food which has a bad smell or which is bitter is like poison to the body. There are also other lesser foods that are not as bad as these just mentioned. Therefore, of these, it is fitting to only partake of small amounts, and even so only to do so rarely, and also to accustom oneself to not to have any of these as a main dish or as a frequent side dish. This category of food includes big fish, cheese and milk which sat more than twenty-four hours from the milking, the meat of big oxen or big goats, broadbeans, lentils, chickpeas, barley bread, matzah, cabbage, leeks, onions, garlic, mustard and radishes–all these are lesser foods. It is only fitting to eat a little of them and in the winter, but in the summer one should not eat of them at all. It is not fitting to eat of broadbeans or lentils in either the summer or the winter. Also, one should only partake of gourd-squashes in the summertime.

Halacha 10. There are some foods which are not as bad as these just mentioned, and they include water fowl, young pigeon, dates, bread which has been roasted in oil, bread which has been kneaded in oil, flour which has been sifted so fine that it no longer has any substance of bran, fish brine and pickled fish oil. It is not fitting to eat a lot of these foods. Someone who is wise–one who has subdued his exuberance and is not pulled by his desires and does not eat these foods except for medicinal benefit is staunchly proper.

Halacha 11. One should always be tempered from the eating of tree fruits, and one should not eat of them excessively even if they have been dried–and needless to say, if fresh. All the more so, before ripe, they are like swords to the body. Carob is likewise always harsh. Tart fruits are also lesser foods, and one should not eat of them except in summer or in hot places. Figs, grapes and almonds are always beneficial to eat, whether fresh or dried, and one may eat of them all that one wants to, but one shouldn’t habitually eat of them even though they are the best of the tree fruits.

Halacha 12. Honey and wine are bad for children but good for adults–especially in the winter. In the summer, one should eat just two-thirds of the amount of these that one partakes of in the winter.

Halacha 13. One should always endeavor to have slightly fast bowels throughout life–close to slightly diarrheaic. This is a very important general rule in health–whenever the urge to defecate ceases or the stool is passed with difficulty, challenging illnesses follow. How might one cure oneself when slightly constipated? If one is young, he should eat well-cooked boiled vegetables early in the morning, salty and seasoned with olive oil, fish brine and pickled fish oil, and have salt without bread. Or, one should drink the water in which spinach or cabbage has been boiled, seasoned with olive oil, fish brine and salt. If, however, one is an older person, one should drink honey dissolved in hot water in the morning, wait about four hours, and then eat one’s meal. This procedure should be followed for one day, or three or four days if necessary, until his stool softens.

Halacha 14. The Sages stated another general rule about bodily health: as long as one exercises and exerts himself well, doesn’t eat to satiety, and is able to maintain properly loose bowels, he will not become sick and his strength will continue to increase, even if he eats bad foods.

Halacha 15. In contrast, anyone who does not exercise, or holds back from relieving himself, or who is continually constipated, will have a painful life and his strength will weaken, even if he eats good foods and looks after himself medicinally. Overeating is like poison to the body, and is the cause of many illnesses. Most illnesses are caused by bad foods and by overeating–even if one overeats good foods. Solomon said in his wisdom, “He who guards his mouth and his tongue keeps his soul from troubles”, that is to say that one should guard one’s mouth from eating either bad foods or unnecessarily, and one’s tongue from speaking except when necessary.

Halacha 16. The way of the baths is to indulge there after seven days. One should not enter a bathhouse shortly after having eaten, nor when one is hungry, but should do so when one’s food has just started to digest. One should wash with hot water of a temperature below scalding, and one should wash one’s head with water hot enough that it would even scald the rest of the body. Then, one should rinse oneself with lukewarm water, then with cooler water, and so on, until one is washing with cold water. One should nor pour lukewarm or cold water over one’s head. One should not wash with cold water in the winter season. One should not wash until his body is sweating and his limbs become slack. One shouldn’t prolong his stay in the bathhouse–once one feels that he is beginning to sweat excessively and that he is beginning to dehydrate, he should rinse himself and then leave. One should check oneself before entering a bathhouse and after leaving to be sure that one does not need to relieve oneself. One should be of similar discernment before and after eating, before and after copulation, before and after doing exercise and before and after sleeping. The total number of times that one should consider these concerns is ten.

Halacha 17. When one leaves a bathhouse one should put on one’s clothes and cover one’s head even while in the outer room, so that one won’t catch a draft. One has to be particular about this even in the summer. After leaving, one should delay further until one is of a balanced composure and one’s body has again relaxed and become warm before eating. One should not drink cold water after leaving the bathhouse, and needless to say, one shouldn’t drink in the bathhouse itself. If, however, one was parched of thirst when coming out of the bathhouse and cannot shake the sense of thirst, he should temper the water with wine or honey and then drink. In the winter it is good to anoint oneself with oil in the bathhouse after drying off.

Halacha 18. One should not accustom oneself to letting blood frequently, for one should not let blood unless absolutely necessary. One should not let blood in the summer or winter, but one should let a little during Nissan and Tishrei [the moderate seasons]. Once one has reached the age of fifty, one should not let blood at all. One should not let blood and go to the bathhouse the same day, nor should one let blood before travelling, nor on the day when one completes a journey. One should rest on the day of letting, and one should not overly exert himself, do exercise, or even go on excursions on the day of letting.

Halacha 19. Semen is the strength of the body, its life and the light of its eyes. The more that semen is emitted, the more does the body weaken, the more does the inner strength dissipate, and does life itself come to its end. Solomon said in his wisdom, “Do not give your strength to women”. As one is obsessed in copulation, does age rapidly follow, does one’s strength disappear, do one’s eyes dim, does an odorous smell exude from one’s mouth and armpits, does the hair of one’s head, eyebrows and eyelashes thin, does the hair of one’s beard, armpits and legs thicken, do one’s teeth fall out, and do many sources of suffering apart from these also befall. The wise of the doctors said that one of a thousand dies of an unspecified condition, while a thousand die because of excessive copulation. Therefore, one has to be careful in this matter if one wants to live well, and one should copulate only when one’s body is healthy and at its strongest and when one’s organ continuously erects without one’s having thought about it, and it stiffens even after turning one’s concentration to other concerns, and one finds the hip region and below heavy as if the testicular tendons are being drawn of themselves, and when the flesh is warm. This indicates a need to copulate, and even that this is its cure. One should not copulate when full or when hungry, but only when one’s food has begun to digest. One should check oneself before and after copulation to be sure that one doesn’t need to relieve oneself. One should not copulate while standing or while sitting, nor in a bathhouse or on the day when one has plans to go to the bathhouse, nor on a day when one lets blood, nor on a day when one starts or finishes a journey, nor on the days preceding or following such days.

Halacha 20. I can guarantee that anyone who accustoms himself to these ways that we have discussed, will not become sick throughout his whole life, and will never need to take any medicines. His body will be perfect and healthy for his entire life, except if his body was imperfect from birth, or if he had been accustomed to a bad habit from the improper habits discussed from early in his lifetime, or if a plague or drought occurred in the world.

Halacha 21. All of these good habits that we have mentioned are suitable to be diligent about only for those who are healthy. If someone is ill, or has an organ that is dysfunctional, or has been accustomed to a bad habit for many years, then there are for each of these situations other specific good habits, depending upon the condition in question, as are explained in medical teachings. Suddenly changing one’s habits or routine however, is also considered a compelling sign of illness.

Halacha 22. In places where there is no doctor, neither a healthy nor a sick person should deviate from any of the advisement mentioned in these teachings, for every one of these methods brings good.

Halacha 23. It is not permitted for a learned person to live in a community that does not have all of the following accessible to them: a doctor, a bloodletter, a bathhouse, a toilet, naturally-occurring water such as a river or spring, a synagogue, a children’s teacher, a scribe, a warden of charity and a Court of Law which is empowered to inflict corporal punishment and jailing.