Very Low Calorie Diets

tuxedord2

I have read all the debate regarding which way is the best way to lose weight. I understand there are several different camps including the eat more vs. eat less groups.

My question is HOW do the "medically supervised doc in a box" weight loss regimes actually work? Many of these have patients on 800 calorie shake only diets. How does the body NOT go into starvation mode? How do these diets actually work?

No, i am not trying to do one of these diets. I am merely curious.. in the science of it all.

Thanks!!

6ftamazon

They don't go into starvation mode because there's no such thing.

healthyfoxx

In my not-at-all-professional-opinion, the "starvation mode" thing is really overhyped. Yeah, your metabolism will probably slow down a bit to compensate after a while, but it isn't like your body is going to literally STOP losing weight all together if you have a big enough deficit. If it did, people suffering from anorexia wouldn't become so skeletal.

If you're eating 800 cals a day and you need 1700 to maintain your current weight (just pulling numbers out my butt here), you're going to lose weight.

WalkingAlong

I don't know a lot about them but I think they work via steep deficits which they are allowed to recommend due to including medical supervision. They probably test people monthly for things like gall stones and the other side effects listed in the link below?
http://www.webmd.com/diet/low-calorie-diets

I think they often include vitamin injections, or at least the HCG clinics seem to, and the old Phen-fen ones did. Not that I've tried any of them.

Hopefully someone with firsthand knowledge can tell you more.

There are easier, cheaper ways! Glad you're not considering it.

Kalikel

I tend to think everyone who loses weight is "in starvation mode." You're eating less than you require, so you lose weight. If you did that forever, you'd starve to death. I do not get what the hell people are talking about when they say "starvation mode." I also don't know what they're comparing it to...what are the other modes?

Each person's situation is different, so there would be as many different answers as to why someone was eating less as there would be people doing it. The possibilities are almost endless.

MinimalistShoeAddict

"Starvation mode" never leads to your metabolism completely shutting down. That only happens once you die.

Your metabolism can slow over an extended period of time if you consume much less than your TDEE.

The truth is that the degree of which metabolism will slow on a very low caloric diet varies greatly based on the weight of the study participants. Here are two extremes:

1) 382 day fast of a morbidly obese (but otherwise healthy) 27 year old male:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2495396/pdf/postmedj00315-0056.pdf

2) 36 men with a healthy starting weight forced to eat at a large caloric deficit (MN Starvation Study):
http://jn.nutrition.org/content/135/6/1347.full.pdf html

Of course both groups lost weight as they were eating at a deficit to their TDEE. However the slowdown in metabolism was greater for the men who were becoming underweight during the experiment.

The more you weigh, the easier it is to maintain a large caloric deficit. Only when you become very lean (and your body starts to run out of adipose tissue to burn) does "starvation mode" become more of a real concern.

Just because a larger person can sustain a large deficit for a longer period of time does not mean they should. The 382 fast had many risks and required constant medical supervision for electrolyte levels, etc. Losing weight at a slower pace (along with strength training) would have preserved more muscle mass.

tuxedord2

Thanks everyone!