1000 cals a day??

unless you are about 4'6" 1000 cals a day is not going to cut it. you are going to be starving your body and at that rate you aren't going to be losing long term fat. You need to ensure you have a healthy load of fat and protein in your diet if you want to lose weight correctly, and 1000 cals just isn't going to cut it.

Why would try and apply a diet which takes no consideration of your weight, height, activity levels and current BF%?!?!?

Work out your own macros and follow them!!!!!

You can drop a pant size or two in 30 days by doing the 30 Day Shred, and eating well.

Sounds much better to me, IMO.

You could just add 200 or 400 more calories to the plan in healthy foods.

You in a hurry to get fit? Then don't waste any time doing Stupid Diet Things. Starting eating right and exercising today.

I survived on less than 800 calories for over 2 weeks. I had no energy, I was always tired and very cranky. But that's just me. I'm interested to hear some more feedback on this.

Why jumpstart?....

Learn to eat healthy for your whole life... that takes some practice... eat in a way that you can keep up indefinitely.
I don't think that 10-days of harsh stress on your body will do you any good in the long run.

I tracked for a couple of weeks before I worried about losing.
(although seeing what I was eating I couldn't help but rein back a bit)

Then I saw where I could make small changes on things that weren't that important to me.
(Don't even think of taking chocolate out of my diet!!!)
--Reducing quantities where I won't notice it so much
--Swapping out things instead of eliminating them.

Then every couple of weeks I check where I can make another couple of small changes.
If you completely revamp your diet, it's way easy to revert to old ways in times of stress.
If you make a series of small changes, food still offers you some sense of comfort.
sort of a comfort continuum, and after a while the first small changes will seem comforting in themselves.

I doubt you'll be thrown into starvation mode unless you go over 3 days without eating. The whole Starvation Mode craze has taken on a life of it's own. You'll be fine. Hungry? Yes. But you won't be literally starving.

Is 10 days of tight food restriction like that enough to throw your body into "starvation mode"?

No, it's not. You'll probably be hungry and miserable, but it's unlikely to do any damage.

If you lose that much weight in such a short period of time, there's no way it's going to be all fat. When you starve yourself like that, your body will actually break down your muscle for energy because protein is easier to break down than fat is.

Sure, you'll lose 10 lbs in 2 weeks, but once you go back to a more normal routine, it'll be hard not to put the weight back on as fat.

Not only will it be fat, but it'll be visceral fat. Visceral fat is the fat underneath your muscles in your abdomen - the dangerous stuff. It'll put more pressure on your internal organs which will increase the risk of weight-related problems.

My suggestion? Don't do it. Or if you do that 10-day thing, eat all your regular calories + the calories you burned off from working out, minus enough to lose 1lb/week. Then you'll build lean muscles, burn off fat, and you'll be able to keep it off! You won't lose as much weight as quickly, but muscles weigh more than fat, and bigger muscles burn more calories to do the same work!

I honestly don't think that it would be a problem...I eat about that many calories a day anyway, and I've never had an issue. However, ignoring what the fear-mongers on MFP say about slowing down your metabolism (which takes MONTHS to do, I might add, and months like closer to a year than two or three) you may just want to talk to your doctor about it.

yeah i wouldn't do that....loosing weight that fast is not healthy a slow steady loss is what is best for anyone trying to loose weight....

lose, not loose

I think those 10 day diets are worthless IMHO. why eat only 1000 to lose some weight and then eat 1200-1500 in 10 days? all you are doing is having a higher calorie deficit which make you lose weight but I would see that you gain it back. i dont see a point in putting your body in such a strain remember 3500 calories is a pound so to me not worth it.

Ah, **** - moment of weakness. I really do know better. The allure of dropping a pants size in 10 days though...... it's freaking tempting.

Yes, it is. And you can do it. But the long-term impact is that you'll have to start eating more at some point, and your metabolism will be so suppressed after the 10 day period that a lot of it will come back on again as soon as you start eating.

If you have some specific reason why you need to be a pant size lower in ten days, and you don't care about your pant size in 15 days, then it's probably not harmful to you at all.

But slow and steady is the way to go for the long haul.