Since I am an insulin-dependent diabetic and kidney patient, I do modify my fasts a little bit when it comes to food and drink, especially since I am already on a restrictive diet. My priest did tell me something to the effect that
when you have such a major illness your fast is to live with your illness and you must do what you must do to take care of yourself with it. So, eat what you must eat when you must eat it. That is your fast. I also will give up something else, such as television for the day or something to that effect.
I also wanted to share the below passage. Hope this helps a little!
CURRENT CHURCH REGULATIONS ON FASTING AND ABSTINENCE
(Source: The Pastoral Companion: A Canon Law Handbook for Catholic Ministry, Franciscan Herald Press: Chicago, Illinois, 1995, pp. 292-96).
*Current Church regulations on fasting and abstinence are these:
Fast: The law of fast prescribes that only one full meal a day be taken; but it does not forbid taking some nourishment at two other times during the day. The two smaller meals should be sufficient to maintain strength according to each one’s needs, but together they should not equal another full meal. Eating between meals is not permitted, but liquids, including ordinary, homogenized milk and fruit juices, are allowed. Malted milks, milk shakes, and the like are not included in the term “milk.” All those from eighteen years of age to the beginning of their sixtieth year are bound by the law of fast on Ash Wednesday and Good Friday
Abstinence: The law of abstinence forbids the eating of meat, but not eggs, milk products, nor condiments of any kind, even though made from animal fat. Forbidden are the flesh meat of warm-blooded animals and all parts of such animals. This does not include meat juices, broths, soups, lards, gravies, sauces, animal fats, and liquid foods made from meat. Also allowed are fish and all such cold-blooded animals such as frogs, shellfish, clams, turtles, oysters, crabs, and lobsters. All those who have completed their fourteenth year are bound to the law of abstinence from meat on Ash Wednesday and on all the Friday’s of Lent.
(Note: There exists no age cut offs on the commitment to do penance in the Association for those who are in formation or profession to live the Rule for life, except that no one can be admitted as a member before their 14th birthday, except those imposed by the penitent in communication with their own spiritual director based on their own needs and situation.)
The substantial observance of the laws of fast and abstinence is a serious obligation. When a proportionately serious reason exists, there is surely no sin in departing from these norms. Thus, one may very well be excused by sickness or any infirmity which requires that one eat meat even on Friday during Lent, by the need to take one’s meals in common, by travel when it is not possible to obtain readily permissible foods, by great poverty, etc.
