Health effects of fasting


Does anyone have any good resources on the health effects of fasting - good or bad? I’ve decided that I want to have a crack at fasting for the full 40 days of Lent this year, and it’s something that I’ve never done before. My medical student fiancée tells me though that it’s not very healthy for me, especially if I’m having my large meal at the end of the day. Perhaps I should have my large meal at lunch instead? Would that be better?


I, too, have thought about this, as well. One of my friends fasted the entire 40 days, last year. What she did was she ate two small meals (like two hard boiled eggs for breakfast, or one piece of toast with jam in the morning, and maybe a half sandwich for lunch…or a small roll with a small bowl of soup for lunch, etc) and then a normal size dinner–consisting of a salad…protein (meat or whatever) and some healthy carbs like brown rice, or sweet potato…or veggies of some sort. That’s what she did, and she lost 20 lbs…which she was happy with, but wasn’t her initial intent. After a while, she felt that her hunger for food, was replaced with hungering for God…and so she would substitute those hunger pangs, with prayer. Now, she also exercised…so, she would drink an energy drink or eat half a banana before working out…(you have to be sensible, and undereating when you’re working out is kind of dangerous) I plan on fasting 4 days per week…and eliminating bread, pasta, and starchy foods on those days–foods that might be hard for me. I wish you luck…but hope that helps?


Yeah it definitely helps, and thanks for the luck. I could also do with some prayers because I think I will struggle. And, if anyone else has more information then that would be great too!


people managed for a thousand years without ill effect, if you are in good health otherwise it should provide no hardship. In our age of supersizing we tend to thing of “too much” as “enough” and don’t realize what a small amount of food is sufficient in most of the world to sustain life and health.


When once married, my then-wife said that when I fasted (on just bread and water on all Fridays), I tended to get irritable. As a registered dietitian, she might have been right. But then again, I remember feeling irritable about a lot of things then.

For a special intention, I once fasted on bread and water for 2 weeks. To be honest, I didn’t find any particular spiritual benefits, but I did come to appreciate the abundant supply of food and drink in our part of the world. I also marveled at the seemingly endless varieties of bread available. I came to see that bread was a worthy symbol of both our unity and our diversity.


When it comes to fasting you must have a specific reason why you are fasting. Are you fasting for the sake of fasting or because there is a specific reason. Some people fast on a Wednesday or Friday. It depends on you I think.

I have specific reasons why I am fasting and I also pray and read the bible everyday. Don’t allow yourself to get tempted have faith in yourself and God. Nothing else matters except him and why you are making this sacrifice.

I have choosen to fast from 6am to 6pm. I am having no rice, bread, pasta, potatoes, red meat. I am only eating veggies and fish or chicken.

Maybe what we should do is set up another thread for those who feel they are tempted and we could prayer together.

What do you guys think.


thank you for the great ideas! I too am cutting out bread, pasta, and starchy foods 4 days per week…and the other three days, I’m still eating much less (the two smaller meals per day with heavier meal at dinner) but can eat bread on those days. Today, I ate bread, but fasted. I feel a little hungry now, but it’s a good hunger. It’s seems like such a piddly sacrifice for all that Christ has done…but I’m also going to mass an extra day during the week, and praying the Rosary and Chaplet daily…I’m not meaning to ‘blow a trumpet’ like mentioned in today’s mass reading:o I’m merely stating that fasting and Lenten paths can take on different shapes for everyone. This is a great thread! and I like the idea of starting one for praying for everyone throughout the Lenten season.:thumbsup:


Actually, you may be causing an even more serious damage to your mental health because it looks like you’re heading into religious fanaticism (obsessive compulsive disorder). I’m speaking from experience. I developed horrendous psychosis, OCD, ADD, and anorexia from trying to be more than what God wanted me to be. I tried living like a monk. If it hadn’t been for the Sacraments (ironically), I would probably be dead today. Amazingly, I never had to go to a therapist (thank God). God “beat” it out of me to put it nicely. Anyway, what I’m trying to say is that unless you belong to a religious order or you’re doing this under obedience, simply abstain from meat on Fridays and fast (one full meal only and two small meals) on Good Friday. Seriously, I speak from experience and you do not want to go through what I went through…


Fasting can and does mean so many things to so many different people that we would need more info before sending you to specific info. There is tons of scientific and not so scientific (experiential0 info on the results of all manner of fasts.

It can certainly be done in a manner that is both healthful and spiritual at the same time. For most people, there are several items in the diet that can be abstained from with no ill health effects, but that will be powerfully missed.

What is the purpose of your fast? What are you trying to acheive, prove, experience? That will make a difference about what type of fast you undertake.

Also, do you have other responsibilities that you must factor in? If you are a student, employee, parent, or caregiver, you might owe someone a certain amount of service that you should not jeapordize by an overzealous fast.

For many, who must still function at work, school, etc, eating a full meal at the start of the day is a good way to go. Eat a healthy meal that provides protein, calories, nutrition to carry one through the day, and at lunch and dinner have a small catch me up. This can be both healthful and spiritually fulfilling. On days off or weekends, you might be freer to do a just liquids, or some such other option.

Also, is it something private and personal, or something you want everyone to know about? Sometimes we choose a very private fast, and that means still going out to lunch with the crew on Wednesdays, and not making an issue of our personal spiritual practices.

So, as another poster said, it is important to define your parameters, and do a little ground work first. And to remember, as time goes on, that it is not about you.If mom makes a special birthday dinner, don’t dis her by saying…sorry, I’m fasting, and making a big deal about it. Don’t pout about how everybody is against you, etc, part of the lesson of the fast is that it is not about “us”. We quickly learn how much, how often and how important food, and eating is in our culture. We gain some important understandings.

Most of us do not have the luxury to go off alone into the desert for 40 days and totally focus on our relationship to God. That is our cross to bear as well.

Even in fasting, we must be open to the Divine plan for us.



I have not had as severe an experience as you described, but I know that excessive fasting in Lent, and fasting at different times definitely was not mentally healthy for me. It didn’t cause any problems, since I have had mental problems since age 12, but it definitely contributed to my problems with bulimia(thankfully, i’m somewhat recovered, but it took hospitalization and therapy). Because of this, I decided to do nothing foodwise(other than required abstaining and fasting) during this Lent. The last thing I need, or anyone needs, is an eating disorder or even issues with food, they can mess you up in horrible ways.


experts, whoever they are that did this sort of research, have shown that near starvation and just above it is the ideal range of caloric intake (when done properally) for optimal health. I always thought that was interesting


What I did this lent was fast for the full period and only eat one meal in the evening. Strangly enough the two effects i’ve noticed are that I felt very tired all the time, had trouble sleeping and put on quite a bit of weight. I wouldn’t recomment it, try two small meals and breakfast is probably quite important.


Yeah, rather interesting. How can you starve “properly”??? Near-starvation destroys the body, how on earth can that be healthy???


*THIS *is fasting? Sounds like normal to me and hardly something that would pose a health concern. I have fasted (nothing but liquids) for up to a week at a time. I rather enjoy the benefits of letting your systems (digestive, skin, nervous) calm down/stabilize as well as some inevitable weight loss. It may sound challenging, but after about 2 days–your appetite adjusts and feeling/fighting hunger is really not an issue. After an extended fast–you also notice a diminished tendency/capacity to overeat and are satisfied with much smaller, more modest portions of food–a physical and spiritual benefit. About the only negative I’ve experienced, if it could even be considered as such, is that fasting may delay/alter your monthly cycle.


Actually yes, this is the definition of fasting at least as it has been presented to me. There are different forms of fasting. I.e. one can give up more then this but if they don’t it is still considered fasting.



Actually, near starvation has been shown to be the best caloric intake when done properally and results in the longest lifespan… i guess there is wisdom in the ancient celtic proverb “the key to longevity is torise from the table hungry, leave the table thirsty, and get out of bed tired”


Trust me, I know, I tried it. Hunger, thirst, getting out of bed tired. I tried them all. Didn’t quite work out. :shrug:


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