The Mitzvah to Fast

It is a positive commandment to fast on Yom Kippur, as it is written: “[Each year] on the 10th day of the 7th month you must fast…this is because on this day you shall have all your sins atoned, so that you will be cleansed. Before God you will be cleansed of all your sins” (Leviticus 16:29-30). One who transgresses and does not fast, in addition to negating a positive commandment, also transgresses a negative commandment.
And anyone who eats even one small sesame seed, or drinks even one drop of water, transgresses a Torah prohibition.

A Sick Person for Whom Fasting is Not Life-Threatening is Obligated to Fast

A person who suffers pain from his illness – as long as his life is not in danger, it is forbidden for him to eat or drink anything. This is because fasting on Yom Kippur is a Torah obligation, and therefore, only pikuach nefesh (the preservation of life) overrides it.
This is the difference between Yom Kippur and the other fasts – namely, on the fast of Yom Kippur, ill people must also fast because it is a Torah prohibition; on the fast of Tisha B’Av, ill people are exempt from fasting; and on the minor fasts, pregnant and nursing mothers are also exempt.
Therefore, individuals sick with the flu, angina and the like – since their lives are not in danger, they are obligated to fast on Yom Kippur. It is preferable for an ill person to lie in bed all day and not go to the synagogue, than to eat or drink anything, because the main mitzvah of the day is fasting, for by doing so, God purifies Israel from its sins. And when an ill person is lying in bed, if possible, he should try to pray to the best of his ability, and if reading from the prayer book is too difficult, he should try to pray in his heart and move his lips in private prayers – but not to eat or drink anything.

Swallowing Medicine

While it is permitted for a sick person suffering from his illness to swallow pills – provided the pills do not taste good, and one takes care to swallow them without water. A person who cannot swallow pills without water should add a bit of soap to the water, thus causing it to taste bad, and with this water, swallow the pill.
Although we have learned that it is a Torah prohibition to eat or drink even the smallest amount, this refers specifically to something edible, but a medicine which is not intended to be eaten, is not considered food. True, there is a Rabbinical prohibition to eat or drink even something inedible (S.A. 612:6-8), but when the intention is medicinal, and not for the purposes of eating or drinking, there is also no Rabbinical prohibition.
Thus, the prohibition of taking medicine on Yom Kippur is equivalent to that of Shabbat, i.e., it is forbidden for one who experiences slight pain to take medicine, but if one is mitzta’er (distressed), it is permitted to take medicine (P’ninei Halacha, Shabbat 28:4-5, footnote 3).
Individuals required to take medicine on a daily basis, are also allowed to do so on Yom Kippur.

Headache Sufferers

If the fast causes one great pain, he is permitted to take pills to relieve the pain. Similarly, individuals suffering from intense headaches due to not drinking coffee are permitted to take pills containing caffeine, or pills to relieve headaches.
In addition, someone who knows that the fast is likely to cause a painful attack, such as a migraine sufferer, is permitted to take pills in advance to avert the onset of a painful attack.

A Dangerously Ill Person

Someone who is dangerously ill and the fast is liable to result in his death, is commanded to drink and eat as needed, because pikuach nefesh overrides the mitzvah of fasting, as is the case for all other mitzvoth from the Torah (Yoma 85b). A person in a state of safek sakana (questionable risk of death) and is machmir (stringent) with himself not to drink or eat – sins, because he transgresses the commandment from the Torah to guard one’s life.
The intention is not merely in a situation in which, as a result of fasting, a significant percentage of sick individuals will die, rather, as long as there is a possibility the fast will cause an ill person’s death or weaken his ability to cope with his dangerous illness, it is a mitzvah for him to drink and eat as necessary. Similarly, if the fast is liable to hasten the death of a terminally ill person on the verge of dying, it is a mitzvah for him to eat and drink as needed, because in order to save life – even for short period of time – it is permissible to eat and drink on Yom Kippur.

Not to Be Overly Concerned

On the other hand, however, one should not be overly concerned, for if we worry about sakanat nefashot (endangering life) over every common illness, in effect, we abandon the halakha which determines that a sick person is obligated to fast on Yom Kippur.
Not only that, but if we overly exaggerate and worry about remote dangers, we would have to hospitalize all sick people, prohibit all non-essential means of transportation for fear of accidents, and of course, prohibit all types of hikes and excursions, and so forth.
Rather, the general rule is: Any danger that people usually treat urgently – investing time and effort – such as rushing a sick person to a hospital, is considered sakanat nefashot, and to prevent it, it is a mitzvah to desecrate Shabbat, and drink and eat on Yom Kippur. But dangers in which people do not rush and invest time and resources to take care of, is not considered sakanat nefashot.

The Greatest Mistake in Eating and Drinking in Shiurim (Measurements)

A common and widespread misconception among doctors and the ill is the belief that the advice to drink l’shiurim (in measured quantities) is sort of a middle path, suitable for sick individuals for whom the fast is not life-threatening. In truth, however, drinking even a little bit is a Torah prohibition, and a person whose life is not endangered as a result of fasting, is forbidden to drink anything.
Rather, the point about drinking l’shiurim is that even when a dangerously ill person needs and is permitted to eat and drink on Yom Kippur, in the opinion of Ramban, it is preferable to eat and drink l’shiurim, so as to reduce to some extent the severity of the prohibition, because one who eats or drinks less than a shiur, although he has transgressed a Torah prohibition, one is not obligated to bring a sin offering and is not punished with karet (having one’s soul cut off from Israel). However, many Rishonim including Rif and Rambam do not mention this instruction, because in their opinion, a dangerously ill person is allowed to drink and eat l’chatchila (from the outset) without any restriction, and this was also the opinion of a number of Achronim (Natziv, Ohr Sameach and others). Nevertheless, the Shulchan Aruch determined that, if possible, it is preferable to drink and eat less than a shiur (618:7-8). All this, however, is on the condition the sick person’s life is in danger.

What is Eating and Drinking in Shiurim?

The shiur for drinking is k’mlo peev (a cheekful of liquid), each person according to the size of his mouth. The shiur for eating is k’kotevet hagasa (a type of large date). In other words, eating and drinking less than a shiur means drinking less than k’mlo peev, and eating less than k’kotevet, which is 30 ml (S.A. 612:1-5, 8-10). The interval between drinking and eating is approximately nine minutes.

Diabetics and a Woman After Giving Birth

However, when there is reason to believe that drinking and eating in shiurim is liable to cause the slightest negligence in the strengthening of the dangerously ill person, he must drink and eat normally. For example, when a yoledet (a woman after giving birth) is tired, it is best for her to drink normally so that she can sleep uninterrupted, and not have to remain awake in order to drink in shiurim.
Diabetics who have not found a reliable solution for their situation must be very careful about this. If there is concern that due to eating in shiurim they might be negligent and not eat as needed, they must eat normally.

Praying in a Minyan as Opposed to Eating in Shiurim

It is preferable for diabetics who need to eat on Yom Kippur to eat more than a k’shiur at one time and pray in synagogue, than to remain at home and eat in shiurim. There are two reasons for this: First, eating in shiurim is a hiddur (enhancement), and praying in a minyan is more important. Second, if ill people are required to remain at home in order to eat in shiurim, some will nevertheless go to synagogue, intending to eat there in shiurim privately, but in practice, due to various reasons, they will forget to eat as necessary, and as a result, become unconscious, faint, and God forbid, die. Diabetics have been known to die on Yom Kippur because of this reason.

Pregnant Women

Pregnant and nursing women are obligated to fast on Yom Kippur (Pesachim 54b; S.A.617:1). Even on Tisha B’Av, pregnant and nursing women are obligated to fast, kal v’chomer (all the more so) on Yom Kippur, whose requirement comes from the Torah.
There are some poskim (Jewish law authorities) who wanted to permit pregnant women to drink in shiurim, because in their opinion, women have become weaker nowadays, and fasting may cause them to miscarry. However, from studies conducted in Israel and the around the world, it was revealed that fasting does not increase the risk of miscarriage. Only in rare cases is fasting liable to induce labor in the ninth month of pregnancy, and in any case, this does not entail sakanat nefashot. Also, there is no evidence to the claim that nowadays women have gotten weaker. On the contrary – today, people are healthier than in the past, both due to the diversity and abundance of food, and because of medical advancement. This is also reflected in the rise of life expectancy by tens of years. Consequently, there is no room to be more lenient than in the past, and the halakha remains firm that pregnant and nursing women are obligated to fast (Tzitz Eliezer 17:20, footnote 4; Nishmat Avraham 617:1).
Thus, even a pregnant woman suffering from vomiting, high blood pressure, low hemoglobin (iron), and various ailments, is obligated to fast on Yom Kippur, and it is forbidden for her to drink in shiurim. Only in a special case where the pregnancy is at risk and by orders of a God-fearing doctor, is a pregnant woman permitted to drink, and it is preferable she drink in shiurim.

Nursing Women

A nursing woman is obligated to fast on Yom Kippur (Pesachim 54b; S.A. 617:1). Although nursing causes fasting to be difficult, because it results in a further loss of fluids, there is no danger to the mother. The baby as well is not in danger, for if its’ mother is the type of woman whose milk does not decrease by fasting, the infant is not affected by the fast at all. And if its’ mother is the type of woman whose milk decreases due to fasting, she can supplement by feeding her baby oatmeal or water with glucose, and thus, the infant will not be affected by the fast.
Some poskim wanted to be lenient concerning nursing women, because in their opinion, weakness has descended upon the world, and today, without nursing, babies are at risk – however, their statements are extremely puzzling. For although surely there are positive benefits to nursing and mother’s milk, and many doctors encourage nursing, nevertheless, there are many women who do not nurse at all, and we have not witnessed doctors waging a war in support of women continuing to nursing in order to save their children for fear of mortal danger. If, in the past, when numerous babies died in their first year of life, and there were no good substitutes for mother’s milk, the clear instruction was that a pregnant woman was obligated to fast – even on Tisha B’Av – how is it conceivable that nowadays, when there are good substitutes, suddenly, this issue has become one of pikuach nefesh?!
Although this is clearly the halakha, one should not object to those who naively rely on rabbis who are lenient. But in regards to rabbis who instruct women to be lenient – the bewilderment is great.
Quite often, it seems what lies behind such opinions is a worldview that ignores the positive aspects of modern living. According to their opinion, the past was wonderful, people were strong, pregnant and nursing women were amazingly healthy. But today, we are miserable, and have nothing better to do but cry and sulk over our bitter fate. In reality, though, our situation today is infinitely better than conditions were a hundred years ago. Life expectancy has increased dramatically, the mortality rate of infants dying within their first year is extremely low, and pregnant and nursing women are much healthier. In the past, twenty percent of women died in childbirth, and today, not even one percent dies. Incidentally, this is the same way of thinking that believes we shouldn’t thank God for the Ingathering of the Exiles and the establishment of the State of Israel – as if the grief-stricken galut (exile) was superior.

When is it Permitted to be Lenient?

However, when a baby is weak and prone to illness and the doctor thinks he is especially in need of mother’s milk, and there is reasonable concern that as a result of the fast, the nursing mother’s milk will stop or significantly diminish – by the order of a God-fearing doctor, she should drink in shiurim (O.C. 617:1). However, this is a very rare case, because if on the day before the fast, a nursing woman drinks a lot of water, almost certainly, her milk will not decrease as a result of fasting.
It is preferable for her to start drinking more three days before the fast, and get more sleep, and thus, her milk supply will increase. In addition to this, she can express milk for a number of meals a few days before the fast, and thus, the baby will have plenty of milk on the fast. Based on the experience of several women, it is advisable to alternately skip two feedings in the afternoon and early evening, and instead, give the baby a substitute, and thus the fast will pass more easily for both mother and baby.

This article was translated from Hebrew.