Questions around intermittent fasting

dee95mfp

Hello, I have two questions around intermittent fasting.

1. My two fast days I am supposed to eat 500 calories. I find this difficult and yesterday I was closer to 700. Does it have to be 500 exactly or is it OK if its less than 1,000?

2. In addition I've been trying to eat two as opposed to three meals a day everyday, good or bad idea?

Jthanmyfitnesspal

It sounds like you're trying 5:2d IF. I do a 2 meal plan of lunch and dinner most days. You can call this "16/8h intermittent fasting" or you can call it "skipping breakfast, no snacks after dinner."

It does not, by itself, cause me to lose weight! To lose weight, I also need to log my meals and not over-eat. The point is that IF is just a tool to help you eat at or below your average daily burn such that you maintain or lose weight. There's nothing more to it than that. It does not make you burn extra calories, in fact, 5:2d can make you more lethargic on the fasted days, causing your calorie burn to reduce. (This is highly dependent on the individual and you definitely should experiment to find what works for you.)

For me, skipping breakfast (or eating a very small breakfast, such as a banana, as I did today) just means I can eat a bit more for dinner, which I prefer. For the 5:2d plan you are following, just log your meals and see if you can more easily keep to an overall deficit. If you feel like you want 700 cals on your low days, so be it.

Best of luck!

Strudders67

With the 5:2 diet, you're supposed to eat your maintenance calories on five days and 500 cals (or 600 if male) on two, non-consecutive days. It assumes you know what your maintenance level is, so I'll assume you do. Is that actually how much you're eating on the other 5 days though? Or are you eating less than your maintenance calories and therefore starting to get hungry because you're not eating enough? IF is seen as a gentler approach to eating fewer calories (and therefore losing weight) than a restrictive diet to be followed 7 days a week. However, it boils down to the same thing: eating less than you need to maintain your current weight = weight loss.

5x MaintCals + 1000 FastingCals = number of calories to be consumed per week. How you split those, per week, is entirely up to you. If you're struggling, you could do 700 cals on the two Fasting days and eat a little less than Maintenance on the other five days.

An alternative is to put your stats into the Guided Set Up page, set a sensible rate of weight loss (losing 0.5% to 1% of your current body weight, a week, is a good guide) and see how many calories MFP gives you. If you use the app, you can look at your food intake as a weekly figure, which is what quite a lot of us who use MFP do. Some days you may eat less, other days you may be out with friends and eat more.

If you exercise, be sure to eat at least some (approx 75%) of the calories burned.

Like jthanmyfitnesspal, I mostly eat two meals a day but in my case it's largely because I prefer to have longer in bed. I too am probably doing 16/8h IF, although I never clock watch. However, it would still be very easy to over eat. I have a big salad (with a good amount of protein) plus a small snack for lunch (total is around 400-450 cals), then I have a proper dinner (with a good amount of protein & a variety of veg), yoghurt with seeds & berries (fibre) plus some wafer thin crackers with thinly sliced, mature cheese on. I then don't feel the need to mindlessly snack later on.

Assuming you're trying to lose weight - do whatever works for you in a safe and sensible way.

DreamOn145

I can only tell you my experience with itermittent fasting. In 2016 I was diagnosed with Rheumatoid Arthritis. I had been misdiagnosed with several other things for several years including severe allergies and chronic obstructive pulmonary disease - in other words I had a LOT of steroids and I was already overweight from PCOS (polycystic ovarain disease). In the spring of 2017 I discovered intermittent fasting through the Gin Stephens books. (she also now has podcasts). I started on the OMAD (one meal a day) program and lost over 100 lbs in a year. I hit a brick wall at 205 lbs and could not budge it, so I switched the every other day dieting plan (5/2) and went on down to 147. In 2018, we moved from Florida to New York and I started slowly regaining weight, but I always maintained my 4-5 hour window and no snacking outside of that. In 7 years I have gained back 20 lbs so now I am back on OMAD. Instead of Ozempic, I take psyllium husks (soluble fiber from a plant ussed as a dietary supplement) which they are now calling "the poor man's Ozempic" It really does help with hunger while you are trying to get used to the intermittent fasting schedule. Of the two types of fasting, I prefer the OMAD, or at least find it much easier to get used to and the 5:2. My advice is to start slow. Give up all snacking after dinner for a couple of weeks, then reduce or give up breakfast. Aim for an 8 hour starting window. From support groups I have been in, not a lot of women lose weight on 8 hours anyway, Men do! My husband has lost over 100 pounds on a six hour window and reduced his insulin from 120 2x per day to 22 units once a day. A lot of information! I hope you find it helpful.

AnnPT77

Keeping it simple, what really matters for weight loss is eating fewer calories than we burn, on average over a fairly small span of time. Let's assume, for the sake of following discussion, that all logging and calorie needs estimates are 100% correct.

If you eat maintenance calories for 5 days, and lower calories for two, how fast you lose weight will depend on how many calories below maintenance those two days are. Putting it a different way, if you eat the exact same number of daily calories every day across a week, that's going to have roughly the same weight loss effect as eating more on some days and less on others to arrive at that same number of average daily calories.

So, what's the difference if you eat (say) 600 calories on your two low days, instead of 500, when eating maintenance calories on the other 5 days? You'd expect to lose about 0.057 of a pound per week less with the two days of 600 rather than 2 days of 500. If it were me, I wouldn't see that as a big enough difference to worry about, especially if eating 600 made it easier to stay the course. Same general concept if 700 instead of 500, except that the weight loss for the week would be around 0.114 of a pound less with 700 instead of 500. It's just arithmetic, plus the assumption that there are about 3500 calories in a pound of body fat. (If you think in kilograms, it's about 7700 calories per kilogram.)

Something like 5:2 intermittent fasting isn't like a magic spell where every detail has to be exactly right or weight loss won't happen. What matters is calories you eat being fewer than calories you burn over any reasonable time period. A week is a pretty reasonable time period. During that week, you can eat the calories in any pattern that works best for you, and ends up averaging an amount less than you burn enough to trigger the amount of weight loss you're shooting for.

Here's an analogy: Let's say you're going to drive enough miles this week to burn 20 gallons of gas, driving about the same distance per day. It doesn't matter whether you fill the gas tank with the whole 20 gallons at the start of the week, or stop for gas every day and buy 1/7 of those gallons each day. You still get to your destinations.

While it's theoretically possible that there are some minor impacts on calorie burn from different eating patterns, there's no research I've seen suggesting that there's a meaningful difference caused by what pattern of calorie consumption you choose . . . other than when one pattern is easier for you to stick with, and another pattern isn't even possible to stick with.

As far as eating two meals vs. three, that's kind of a similar thing when it comes to weight loss results: It's the total number of calories across all your meals that matters, not how you divide them up over the day. Whichever pattern is easiest for you to stick with will probably give you better results. Personally, when losing, I usually ate 3 meals, but occasionally 2, and even more occasionally 4, but did have some snacks sometimes. Following whatever eating pattern made any given day work out seemed to work best for me. It wasn't even consistent.

Looking at it only from the perspective of the weight loss goal, I'm always going to suggest people pick the easiest method that leads to the result they want. Why make things harder? Seems like that would reduce odds of success.

Best wishes for achieving that success, BTW, because the quality of life improvement that results is more than worth the effort it takes to get there, IME.