Okay, we're talking 60 lbs in 5 months--averaging 3 lbs per week? To be followed by high stress and activity, with you-eat-what-we-serve food options in a military environment while the weight loss must be maintained or increased? I found in Army basic that I gained at first upon exposure to their menu.

I'm not optimistic, I have to say--this is exactly the type of goal that leads toward frantic/self-destructive behaviors, so your concern is warranted. On the positive side, I assume her motivation is very high but I have to ask, wouldn't this be a terrific goal for a YEAR from now? I'll assume you already addressed that and it "has to be" this September.

I'd actually suggest moderation of activity and let the Air Force build her musculature once she's there. Muscle is heavy! IF is relatively neutral re: weight loss. The eating window doesn't determine low/full/excess energy intake. Again, with high motivation the discipline of IF can be reinforcing if she likes it.

With such a short total time and the likelihood that weight loss is likely to slow at some point, if she's going to do this you should research and discuss/dismiss a short-term strategy for the first month that would be something like CR (extreme calorie restriction) or ADF (alternate day fasting) or even a step like a 2-week water-fast. That assumes the final 3-4 months would involve moderate, balanced nutrition and activity to reach goal--and that's when IF might make great sense.

I wish you both success no matter how you two decide to define it.

I only mentioned the above because most people won't average 3 lbs of weight loss per week over a 5 month spell of moderate diet/IF.

I am not in any position to suggest any sort of protocol for anyone*, but I can say that many of the smart paleo gurus, like Robb Wolf, warn people away from such fasting UNLESS everything is locked in.... meaning, diet, sleep, exercise, etc. Once everything is in order, then these smart guys say that it's okay to give IF a try.

Intermittent fasting can be tough on a person, particularly if he/she isn't squared away and ready to take on any added stress.

*I'm just some guy who reads a bunch and tries to experiment/implement things and see what works for me.

Please test her on the AF PT test qualifications and post those numbers, waist measurement, max push-ups, max sit-up, 1.5 mile run...

While she needs to meet the weight standards - the test qualifications are super important. She needs to test in these areas at least once a week with you - in my own humble opinion... This can be counted as a workout, but must be done and tracked - no matter how poor she does. It will show how she is improving as one should treat a PT test like a sport. It is sport specific training - while other exercises are good and will help, the test needs to be done weekly for muscle memory and practice - this is an open book test...

If you can successfully pull off intermittent fasting as an obese person, nothing works better at curbing future binges. But for a person who is a binge eater, it may not be the best solution (very high recidivism). Personally I've found very strict low-carb to be the ticket for initial weightloss, and after a month or so of that, then attempt IF.

But if you insist - To really pull it off successfully (in my experience as a recovering obese person), she needs to be keto-adapted first.

For me, this would mean having a VLC/ZC meal with no "soft" dairy (butter and hard cheese is ok - cream cheese, sour cream, milk is not ok) in the early evening (before 6pm if she beds at 9-10pm or so) before a fast. Fast until 2pm or so the next day, but keep the eating window very short compared to say, leangains - eat maybe two meals in a 4-hour window (or as I do, one fairly large meal). Perform this protocol three times in a week and in a week's time, she will be fairly keto-adapted.

However, I would like to offer another alternative...

You can't fix a broken engine by driving it faster, no matter what quality of fuel you put into it. You have to fix it first. So I suggest:

1. Moderate Exercise (1-2 weightlifting sessions per week and increased locomotion i.e. walking/biking/swimming)
2. Adequate Sunlight (1 hour a day minimum, 3-4 hours a day awesome)
3. Very low carbs initially to keto-adapt and also quickly shed water weight (seeing the scale shift downward is a great initial confidence boost).

Those three things and I think she will be able to succeed at getting an initial boost of 8-10lbs in the first few weeks from decreased water retention and a repaired endocrine system.

Once that stalls, then it's time to bring out the IF, tinkering with carbs, activity level, etc... but the first thing to do is to fix the problem.

I have a good friend that went from 380 on 02/14/2011 to under 230 in about 9-10 months. He IF'd everyday, basically eating within a 1-2 hour window and virtually zero carb. I'm not sure that's the right plan for everyone but it worked for him. Also, no exercise outside of daily tasks.

When I was seriously dieting, I would weight my food. I'd eat 4oz of meat, possibly a similar amount of vegetable and then wait twenty minutes. If I was still hungry, I'd eat again. When I established this behavior appetite suppression from the Shangri-La Diet had just kicked in strongly, so I got full pretty fast. I was able to stay under 1500 calories using this approach.

IF seemed pretty exciting, but it does seem to be the sort of thing you have to have everything solid in order for it to work. I liked not having to bring food to work, but life kept getting in the way of keeping that lifestyle up. (I don't know that I ate enough during the evening either, so if I ever do it again I will aim for more calories.)

Since she's still overweight, I'd suggest a kitchen scale could be more helpful than IF. And I only suggest this because she has a deadline- otherwise I encourage her to just eat normal paleo and develop some healthy relationships to food.

Not so bad of a predicament. I am a very strcit Paleo guy, but seriously the answer is Atkins. Read his book or even Gary Taubes " What makes us Fat" Regulate insulin. Stimulate Hormone release by exercising. Heigh rep weights is my suggestion. Discipline is going to be the key. Can't see why it's not unattainable. Don't skip meals. Eat "good calories" Good luck