If you are trying to drop body fat in a hurry then maybe you have read about a protein sparing modified fast, or PSMF. If you haven't heard about it then today we are going to dive into the basics about it and why it would or wouldn't be a valuable tool for your needs.
What is a Protein Sparing Modified Fast Diet (PSMF)?
At the core a protein sparing modified fast diet is all about making sure you consume adequate protein so you don't lose muscle mass while cutting short the energy supply so your body focuses on using your body fat for the missing fuel.
As long as you keep the levels of protein up your body will continue to spare the body and muscle proteins leading to a better level of fat loss, though this is meant to be done in short cycles and not intended to be run for months at a time which is why I feel it is a "Crash diet" in terms of fast measurable results.
What is the Purpose of a PSMF?
A PSMF approach is a temporary diet meant to kick-start rapid weight loss in people who are already severely obese. In the study discussed below, it was used for adolescents with severe obesity who had not succeeded with conventional weight-loss methods, inside a supervised clinic program.
What to Eat on a Protein Sparing Modified Fast?
You want to aim to eat very protein high and fat low foods, as this will help ensure you stay satiated.
In the clinic program cited below, the authors note that "the diet is not nutritionally complete," so patients took supplements as part of a supervised protocol (source). Supplement choices and doses belong in that conversation with your clinician, not on a general website, so this page no longer lists them.
A note on ECA stacks: an earlier version of this page listed an ECA stack (ephedrine, caffeine, aspirin). That has been removed. The FDA has banned dietary supplements containing ephedrine alkaloids because they have serious safety risks (NCCIH). CarnivoreRx does not recommend an ECA stack.
Is PSMF Safe?
The protein sparing modified fast was studied in a small 2016 Cleveland Clinic report (source). It included 12 adolescents with severe obesity who were evaluated in the clinic's Obesity Management Program, had not succeeded with conventional weight-loss methods, and went through a supervised refeeding phase.
Results show that the PSMF diet can be used as an effective and safe method in the outpatient setting for rapid weight loss in adolescents with severe obesity
The Protein-Sparing Modified Fast Diet
That conclusion applies to adolescents in a supervised clinic setting. The authors describe the PSMF as requiring "a multidisciplinary approach" with "medical, nutritional, and behavioral components," and report that participants "are at risk for electrolyte abnormalities" and were closely monitored with laboratory tests (source). The study does not show that an unsupervised PSMF is safe for everyone.
PSMF Tips & Tricks
Eat Real Food - To feel full and satiated you need to focus on real foods which require chewing, avoid protein shakes and liquid foods as they have less ability to help you feel full.
Use Spices, Salsas, and Mustard: Most of these are zero calorie and can help you to add a ton of flavor. The plan should be to cycle them day by day to make the foods more interesting.
Final Thoughts on How To Do a Protein Sparing Modified Fast
Leave a comment below if I missed something as I am not a super expert just sharing what is working for me and has worked for me, this means I definitely may not know something awesome you can share!
This article is general information, not medical advice. It does not diagnose, treat, or recommend a diet for any individual.
If you read this far you are amazing! I would love to hear from you in the comments below if I helped you gain knowledge and useful information, additionally I would like to know if I got anything incorrect that you believe should be researched more and updated. As always to get the word out please join our new Carnivore Rx group on Facebook and share this out on social media!
This article is general information, not medical advice. If you have a medical condition, take medication, or are pregnant or breastfeeding, talk to a qualified professional before making major changes to how you eat.
Written by Josh Koop and updated by the CarnivoreRx Team. How we write and update articles.
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