I’m not a doctor, this is just my personal experience. Perhaps it might be useful for some.
About four years ago I lost the “magic” of not really gaining weight postpartum. Previously, it was gone within a couple of months, breastfeeding rapid-gaining babies did cause massive calorie deficits and I was mostly dealing with the physical changes of widened shoulders and hips when clothes shopping.
Then it finally hit. I gained a lot of weight very rapidly and didn’t know where to go from there. So I went with the basics. Ate less, moved around more. This resulted in some weight loss, but I was constantly irritable and thinking about food I wasn’t eating. There were a lot of hunger pangs as well.
I had a major health issue crop up that made it very hard to move around more, and the weight returned. The weight issues made the health situation worse, so I started casting about for another approach. I tried counting “macros”, and I did a little better with weight loss, but it was truly exhausting to try to eat that way. Many women for whom that strategy is effective eat a lot of shelf-stable things that lend themselves to mixing and matching based on protein/fat/carb content, or they are super relaxed about eating 87 of the exact same macro-measured salad in a row.
Long story short I was losing weight for a month or two and gaining it back and then I looked into fasting. Fasting female fans were showing stable weight loss, but more to the point they were showing stable *fat* loss and months between much lower regains than the other dieting approaches I’d used. That women were having this result was very key to my decision to try fasting. Some dieting approaches are better for men than women, and men don’t always think about that if they get good results and promote it to both men and women.
I had reasonable concerns about whether fasting was safe or sensible for my body. All the kind of entry-level WebMd or casually asking a doctor information is that for most overweight or normal weight people not eating for up to 24 hours is probably fine. Again I’m not a doctor, and I’m not saying doctors prescribed me a fasting schedule (although this is certainly something people can and do work out with a physician). What I did learn, that does fall under the “forbidden knowledge” heading is that the typical concern is electrolytes and dehydration. Medically prescribed or arranged fasting generally deals with this via IV fluids.
Or you can just make your own cheap electrolyte mix. There are a lot of recipes online, the simplest is salt+nosalt, or sodium+potassium. With a basic electrolyte mix to drink, fasting became something that seemed low-risk to try for more than 24 hours. And that was what I found to be the case.
Fasting for 48-72 hours has many different names, and the approach with electrolyte mixes is just one of several, but seemed safest to try to me. Fasting for this long puts many people into ketosis, which 24 hour fasting does not. Ketosis is supposed to provide better and more lasting weight loss.
I have over the last year done 48 hour fasting and “intermittent” fasting of not eating for 16-24 hours. The 48 hour fasting gave very different results than my previous dieting. I lost more inches at the same scale-number. It was a 3 inch difference, same number on the scale, with about 18 months between weights. I didn’t crave or obsess about food after the first 24 hours. I lost a little more weight on a monthly basis, but it was all at once and without changing my eating the other days of the month. I did not do 48 hour fasts every week. I did do several monthly.
When I did 16-24 hour fasting, I didn’t get the all at once weight drop, but I did see more consistent weekly weight loss than with conventional dieting. I did that kind of fasting for 3-5 days probably a half dozen times, but not in the same months I did a 48 hour fast.
Fasting is easier for me than conventional dieting (lol just don’t eat for a while!) and the weight loss is stickier. There’s also real fat and inches loss that outpaces the drops on the scale. I do drink electrolytes (salt+potassium, 0 calories in plain water) when I do a fast over 24 hours, but I don’t worry about it if it’s 16-24 hours.
The upshot is that a year later, doing less than one fasting style a month, I’m at a low weight I previously had to aggressively diet and sprint to reach and saw total regain within weeks on. I haven’t faced total regain. I even went on vacations with lots of high calorie food to eat in groups and saw no weight gain.
It’s been working so far. If it only continues working as well as it has another year, I’ll be back to my most recent post-pregnancy weight, but with more muscle and probably as much as 4-5 more lost inches. And all while never having to turn down food at social events. The fasting protocol I’ve adapted emphasizes arranging to fast only when you aren’t facing social gatherings on the grounds that it’s impolite to bring your dietary weirdness into social stuff when you can just eat the darn cake or hot dog. This works well for our social life.
That’s my experience with fasting the last year. I’m skinnier without sagging skin and with less stress about food.