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By Rabbi Doniel Neustadt | Series: | Level:

A discussion of Halachic topics related to the Parsha of the week. For final rulings, consult your Rav.

In several places the Torah warns against the ancient practice of eating the blood of animals, which was an integral part of demonolatry and other forms of idolatry(1). Today, when meat and poultry are already koshered before they arrive in our kitchens, most of us have virtually no contact with animal blood. There does exist, however, the possibility of transgressing the prohibition of eating blood even in this day and age. The following are cases in point:


A blood spot in an egg is not kosher and could possibly render the entire egg not kosher. However, blood in an egg is not forbidden because of the prohibition against blood; rather, it is forbidden because it indicates the beginning of the formation of an embryo inside the egg, and we are forbidden to eat embryos(2).

The majority of eggs, however, do not contain blood. Accordingly, one is not required to inspect an egg to see if there is blood in it, since we can assume that this egg is like the majority of eggs, which are blood-free(3). Since, however, it is an age-old custom(4) ??practiced throughout the entire Diaspora(5) ? to inspect raw eggs before using them, we do inspect them(6). [It is permitted to eat hard-boiled eggs which were not checked before cooking and cannot be checked once they are cooked, since in this case we rely on the fact that the majority of eggs are blood-free7.] B’dieved, if the eggs were not inspected, the food may be eaten(8).

Nowadays, there is an additional factor to consider. In the United States, Israel, and other countries, the vast majority of eggs are “battery eggs” from which chicks are not hatched. Thus any blood found in them does not prohibit their use. All that is required is to throw away the blood spot; the rest of the egg is permitted. Several contemporary poskim hold, therefore, that today we may be lenient with blood spots in eggs and permit eating the egg, the food with which it was mixed, and the utensils in which it was cooked(9).

Harav M. Feinstein takes a stricter approach(10). Although he, too, agrees that according to the basic halachah, battery eggs are permitted, he still advises that it is proper to be stringent and throw away the entire egg, since there is a minority of eggs on the market which are not battery eggs(11). Harav Feinstein reasons that the centuries-old custom of inspecting eggs and throwing out the bloody ones should not be abandoned(12), particularly since eggs are relatively cheap and people do not consider throwing away a bloody egg to be an unjustifiable sacrifice(13). Based on this view, the following rules apply:

  1. All eggs should be checked for a red or dark black spot. A brown spot is not a problem(14).
  2. If a spot is found, the egg should preferably be thrown out. If a lot of blood is found [especially if it is found in different parts of the egg], it is strongly recommended that the entire egg be thrown out, since this is a marked indication that it may not be a battery egg(15).
  3. If the egg was not checked and blood was found later when the egg was mixed together with other eggs or other food, the mixture does not have to be thrown out. The blood itself must be removed and discarded.
  4. Once the blood is mixed into the food and cannot be removed, the food is nevertheless permissible to eat. The dishes do not become non-kosher nor do they have to undergo a koshering process, although it is proper to wait 24 hours before using them again(16).


Although human blood is Biblically permitted(17), our Sages forbade it because it looks just like animal blood and it may seem to an onlooker that animal blood is being eaten(18). But the Rabbis forbade only human blood which is detached completely from the body, not blood which is still “within” the body. Therefore: If one is eating a slice of bread and blood from his gums stains it, the blood -along with a sliver of bread(19)- should be removed from the bread(20). The bread may then be eaten. If the same happens when one is eating fruit, the fruit must be washed off well and then it may be eaten. Bleeding gums may be sucked and the blood swallowed, since this blood is considered as if it has not become detached from the body(21). A bleeding finger may be sucked but it is questionable if the blood may be swallowed(22). [Once the bleeding ceases, one should not stick the blood-stained finger into his mouth, since it appears as if one is sucking the blood(23).] Human blood which inadvertently got mixed with food (such as blood from a cut that dripped into food) may be consumed as long as no bloody redness is visible. This is true even if there is more blood than food in the mixture. If redness is visible, then the food may not be eaten, even if the volume of the food is sixty times greater than that of the blood(24). If blood gets mixed into food, additional food may be added to the mixture in order to make the blood invisible(25).


On Shabbos and Yom Tov, it is forbidden to suck or squeeze out blood from a wound(26). On Shabbos and Yom Tov, it is forbidden to suck blood from one’s gums(27). It is permitted to peel off a scab on Shabbos and Yom Tov(28) if it will not result in blood oozing from the wound(29). To stop minor bleeding [e.g., a nose bleed], it is preferable to use a paper napkin or tissue(30). If none is available, a cloth [preferably white or light-colored] may be used(31). To stop major bleeding, use whatever is at hand.


1 Explanation of Rambam in Moreh Nevuchim 3:46. See also Ramban’s commentary to Kedoshim 19:26.

2 Talmud, Chullin 64b.

3 Rama Y.D. 66:8.

4 Ibid.

5 Aruch ha-Shulchan 66:32; Kaf ha-Chayim 66:41; Igros Moshe Y.D. 1:36.

6 It is clearly forbidden to close one’s eyes so as not to see if there is any blood in the egg (Ma’adanei ha-Shulchan 66:68).

7 Y.D. 66:8.

8 Aruch ha-Shulchan 66:32, who adds that if the blood is visible [as it is sometimes when egg yolk is smeared over unbaked challah as a glaze] it should be removed.

9 Minchas Yitzchak 1:106; Yechaveh Da’as 3:57.

10 See also Responsa Kinyan Torah 2:7 who takes a more stringent approach, but for different reasons, which do not apply on today’s farms.

11 Igros Moshe Y.D. 1:36.

12 Harav Feinstein points out that according to the basic halachah, even “normal” eggs do not have to be checked, yet the long-standing custom contradicts that. We, too, should honor the custom.

13 It seems clear, though, that in a place where eggs are expensive, one may rely on the basic halachah and permit using the egg; see Yechaveh Da’as, ibid. who makes this point.

14 Darkei Teshuvah 66:23, quoting several poskim.

15 Igros Moshe Y.D. 1:36.

16 Igros Moshe O.C. 3:61. This stringency applies only if the bloody eggs were cooked or fried in a pot or pan, not if they merely came into cold contact.

17 Talmud, Kerisus 20b.

18 Rashi, Kesuvos 60a.

19 Based on Yad Yehudah Y.D. 96:5.

20 Y.D. 66:10.

21 Ibid.

22 See Darkei Teshuvah 66:68, who quotes a dispute among the poskim as to whether this blood may be swallowed or not. Darkei Teshuvah does not decide the issue, while Kaf ha-Chayim 66:47 rules leniently.

23 Kaf ha-Chayim 66:48, quoting Ben Ish Chai.

24 Yad Avraham, Y.D. 66:10; Darkei Teshuvah 66:71.

25 Darkei Teshuvah 66:72.

26 O.C. 328:48.

27 Mishnah Berurah 328:147. See Magen Avraham 328:53 who suggests that this action may be Biblically prohibited.

28 O.C. 328:22.

29 Sha’ar ha-Tziyun 328:67.

30 See Shemiras Shabbos K’hilchasah 14:19.

31 Mishnah Berurah 328:146.