# How long before starvation diet slows your metabolism?

**URL:** https://boards.straightdope.com/t/how-long-before-starvation-diet-slows-your-metabolism/404696
**Category:** Factual Questions
**Created:** [May 19, 2007, 4:42am UTC](https://boards.straightdope.com/t/how-long-before-starvation-diet-slows-your-metabolism/404696 "2007-05-19T04:42:03Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![Tenar](https://avatars.discourse-cdn.com/v4/letter/t/35a633/32.png) [@Tenar](https://boards.straightdope.com/u/Tenar)
#### Post date: [May 19, 2007, 4:42am UTC](https://boards.straightdope.com/t/how-long-before-starvation-diet-slows-your-metabolism/404696/1 "2007-05-19T04:42:03Z")

</div>

I’m thinking about trying Optifast for awhile, but don’t want to totally destroy my metabolism and increase the (always substantial) odds of a fast weight regain by making my body go into starvation mode and start conserving calories. Does anybody know (with cites, if possible) how long on average a person can maintain a very low calorie regimen before their body catches on and slows their metabolism to a crawl? My hope is to do Optifast long enough to get a head start on dieting, then switch to something not quite as brutal before my metabolism is too badly screwed.

For the record, I am morbidly obese and am painfully aware that any substantial weight loss will decrease the calories it takes to maintain my body, thus necessitating a lower calorie intake to keep on losing. I am also aware that exercise helps keep metabolism up. I am not asking about the effects of a lower body weight, I am asking about the body’s response to starvation.

Please note that the question I am posing relates to metabolism and is not a request for critiques of Optifast in particular or dieting in general.

Thanks for your help. 🙂 I probably won’t check back for answers till the morning.