I'm confused. I've heard people say if you drop under 1,000 calories a day, your progress will slow down. I've heard people say that they were having trouble losing so they bumped up their calories and started losing again.


So... how do very low calorie diets work then? The ones that are 800 calories or less?

Does your body really slow down or is that a myth?

My sister's doctor recommended she do a vlcd and I'm just wondering.

I've heard it slows your metabolism...?

They don't. At first sure, it works. You lose tons of weight. But it slows your metabolism and you kind of have to stay eating less food for a while not to gain it back. But metabolism stays suppressed. Then one day something goes wrong in your life, loved one sick, your sick and you eat normal. And gain most of it back. I would do it if you had to for some urgent health need or something but, otherwise.. no.

Look, in my opinion this metabolism stuff all comes down to physical activity. You build a metabolism by eating healthy and exercising. At very low counts, you won't be able to exercise (too much fatigue and muscle wasting). So you eat less but burn less. And then you are screwed. You need to find a happy middle ground. Where you eat clean, low-ish calorie and exercise a lot. That sets your metabolism on fire. In a good way.

I chose to do the VCLD as an experiment and it failed. But it doesn't fail for everyone. My conclusion is a bit different than Ians. I think the key to metabolism is volume. Your stomach senses volume and tells the body to keep burning at a normal rate. That volume can either be low calorie volume or high calorie volume. If your stomach senses your not getting volume it will tell the body to slow the metabolism.

The VLCD I did emphasized volume. They insisted that you have mostly their high volume foods. They said "more is better" but for me... it didn't work. And I just think that it isn't possible to replicate the volume that you need for a healthy metabolism with their foods. If you suppress your metabolism no amount of exercise will do much.

That could work too. I do eat a lot. But low calorie-ish. My lunch weighs 2lbs.

I think this is right.

With exercise as a boost.

So does your body actually permanently slow down...? To me that doesn't sound true, but I'm reading a thread on here where a woman is saying that by the time you reach your goal weight, your metabolism will be so low that increasing calories will cause a massive weight gain.


Also, the thing about eating high volumes of very low calorie foods sounds like that would help.

I have a related question.. I would not be able to keep up a diet that allows 800 calories a day, but I've been on a 1200-calorie limit for a few days. It's going well, except..

I've just calculated my basal metabolic rate, and it should be more like around 1500 calories a day. I thought it was supposed to be counterproductive to consume less calories than your bmr. Really confused right now as to whether I should be increasing my calorie limit even though I physically feel fine.

I know that you create a calorie deficit (to lose weight) by dropping the amount of calories you consume lower than your BMR.

Not permanently but it can take (in my case) over 2 years to get back to a strong metabolism. There are many studies that show that reducing calories for a significant period of time reduces your metabolism as much as 50%.

This is exactly what happened to me. When I got to my lowest weight, my metabolism was super suppressed. At 900 cals. I just maintained. If I ate 1200 cals.. I gained, a lot, and fast. Exercise did nothing. If your metabolism is suppressed it can reduce the calories you burn when you exercise. I actually saw this happen on my blood tests (the plan was medically monitored). My TSH went up and my cholesterol went up. Classic signs of hypothyroid. It could not have been what I was eating because the plan was basically controlled shakes. But I was not hypothyroid... just my thyroid was reduced.

Recently I saw a study that said your gastric cells control your leptin reuptake. So your stomach lining cells tell your brain the status of your eating. I also saw a study that said when you go on a diet you "stomach" doesn't shrink but your gastric cells do in response to less food. So my theory is that your gastric cells shrink sensing less food for a period of time and send less leptin to your brain.

It isn't about calories, but about volume. If you give your gastric cells enough volume so that they don't shrink they will send appropriate signals to your brain to keep the metabolism up. This also is the same for people who take like 1x per week breaks and cheat. Likely the increase in volume keeps the body from thinking you are starving and shrinking the gastric cells.

You have to reduce calories under your BMR to lose. But it is my theory that your body needs a particular volume per day. If you reduce calories such that it also reduces volume... you will eventually get in trouble as your body will tell your brain to slow your metabolism via thyroid.. etc. But if you keep the volume high (with vegies etc) and calories low... you can create a defect and keep the metabolism high.

Yes. But my plan told me not to exercise at first. The problem was that once I started exercising -- 3 months in... I was burning off anemic amounts. Keep the metabolism high and you will see the bang for the buck that everyone claims you will.

I wonder how much volume keeps your metabolism up

Thanks Ann. I'll remember to keep up the volume of my foods. I think I do that anyway, since I HAVE to eat loads of vegetables not to get hangry. ;-)

There's a book and plan for that actually. It's called Volumetrics. There's a group and thread on that here in the forum. One cool part is that the people doing the plan all seem really satisfied with the way they're eating. There are some great recipes and meal ideas there too.

Yes. One reason I never got into it before was because everyone said it was to keep you from being hungry. Problem solved. Many times about 4 weeks into any diet my hunger would turn off. Now I feel like that was a sign that I was sabotaging myself.

No, you build a metabolism. Eat healthy (perhaps a lot of healthy stuff) and exercise a lot.