All must fast, including a Chosson and Kallah during the week of Sheva Brochos, and Baalei Habris (i.e. the Mohel, the Sandek, and the father of the baby).
One who mistakenly ate during the fast must immediately resume fasting.
Mothers who are pregnant or nursing, or have difficulty fasting while tending to young children, should consult with a Rov. [One shouldn’t be unduly strict in this regard, so as not to harm the wellbeing of mother and baby.]
One who is ill or elderly should consult with a Rav.
Anyone below Bar/Bas Mitzvah need not fast. From age nine upwards, the custom is to train children to fast for several hours, as per the child’s abilities. [One should not be unduly strict in this regard.]
An individual exempt from fasting should eat in private only, and avoid meat, delicacies or excessive intake. Similarly, children who are old enough to understand the concept of a fast day should avoid delicacies and meat.
