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The High Performance Journal - February 11th, 2025

The other day, I had a conversation with a client who was starting our coaching program.

Like many other clients, he had 20+ lbs to lose, most of which could be found on his belly.

We put him on a special diet to start his program and as he was following the plan, he asked this question,

"Dan, I'm eating the foods you're asking me to eat but I'm finding it hard to hit my calories. What should I do?"

I advised him to forget the calories and ensure he was hitting his protein goal and taking his supplements while sticking to his workouts. That's it.

In 2 weeks, he dropped 12 lbs off his body!

Yes, some of it was water and glycogen, but a significant portion was fat.

He was following a specific diet that most of our clients use when starting their program.

It's called the Protein-Sparing Modified Fast, or what I like to call the Extreme Fat Loss Diet. It's one of the most ethical ways to lose a large amount of fat in a fast amount of time.

The Extreme Fat Loss Diet Explained

What Is The Protein-Sparing Modified Fast?

The Protein-Sparing Modified Fast is a restrictive, short-term diet designed to lose fat rapidly while maintaining muscle mass and minimizing hunger.

Weight Loss Vs. Fat Loss

I call the PSMF an ethical way to lose fat fast because it's designed to help you lose fat, not just weight.

Weight loss is a decrease in overall body weight, including water, muscle, and fat loss.

Fat loss specifically targets reducing body fat while preserving lean muscle mass.

This distinction is important because muscle is your longevity organ and what drives metabolism.

The Protein-Sparing Modified Fast (PSMF) is optimized for fat loss because:

1. High protein intake preserves muscle mass
2. Severe calorie restriction forces the body to use fat for energy
3. Low carbohydrate intake reduces insulin levels, promoting fat-burning
4. Minimal fat consumption ensures the body utilizes stored fat

This diet aims to improve body composition rather than just reduce overall weight by maintaining muscle and primarily burning fat. Its goal is to lead to more sustainable and healthier results.

Benefits Of Doing The Protein-Sparing Modified Fast

We've seen a few cool things happen when clients perform this diet:

• Massive initial increase in fat loss
• Big initial reductions in inches lost around the belly
• Changes in tastebuds when it comes to foods
• Increase in energy levels due to dietary changes
• Decreased hunger due to taking in adequate amounts of protein
   

Who Is This Diet For?

1. People looking to jumpstart their fat loss goals

This diet is suited for people with a good amount of fat to lose (guys over 20% body fat and women over 30% body fat).

Now, this is going to sound a bit controversial, but it's been proven by science:

Under the right supervision, the best way to jumpstart fat loss is to get faster results in the beginning. This can lead to increased motivation, which can go a long way toward creating a healthy lifestyle.

The caveat is that you only do it for a short time and then gradually evolve to a more moderate diet.

2. People looking to get in shape fast for an event

This could include getting lean for a vacation or, in extreme cases, bodybuilding competitions or photoshoots.

3. People who are in the obese range of the BMI or taking weight loss medications like Ozempic

The fast results, coupled with the muscle retention effect of protein and resistance training, make this ideal for those dealing with obesity or who are taking GLP-1 medications.

Who Is This Diet Not For?

1. Pregnant women
2. People under the age of 18
3. People over the age of 65 years old
4. People with pre-existing medical conditions
5. People with a history of disordered eating condition
6. People who are already lean (sub 10% body fat) or underweight
   
   

Safety Concerns of Doing this Diet

When it comes to anything in life, there are no free lunches. While this diet works fast and helps you retain muscle, you should approach it with caution and preferably under supervision.

The big risks are nutrient deficiencies and electrolyte imbalances due to severe caloric restriction, which can be mitigated through supplementation (more on this later).

You could feel fatigue, headaches, and constipation in the short term.

Lastly, I want to reiterate that this is NOT a diet you should follow for a long time. It's a short-term diet that needs to evolve into a more moderate, sustainable eating style.

How to Do The Protein-Sparing Modified Fast

Image courtesy of psmfdiet.com

The Instructions:

• You eat at least 1 to 1.25 grams per pound of body weight only through single-ingredient nutrient-dense protein sources.
• You eat less than 20-50 grams of carbs per day.
• You would spread this out over 3 to 5 meals throughout the entire day
• You would do 3 mandatory resistance training sessions a week
• You get your fats mainly from protein sources and supplements (2 sections down).
  
  

The Foods You Would Eat:

• Lean proteins: Chicken breast, fish, egg whites, lean beef
• Non-starchy vegetables: Broccoli, spinach, cauliflower
• Avoid: Starchy vegetables, grains, fruits, added fats
  
  

Supplements To Take:

Dan Note: All supplements I recommend are linked in the article 

• A high-quality greens powder or multivitamin​ 
• Omega 3's​ 
• ​Electrolytes​ 
• ​Magnesium​ 
• ​Creatine

In our coaching practice, we highly recommend taking these supplements to compensate for any deficiencies caused by a diet of this nature.

In general, I would recommend these supplements regardless of whether I am going on this diet or not.

How Long Should You Do It For?

I recommend no longer than 14-16 days for someone trying to jumpstart fat loss.

If someone is obese and under medical supervision, they can technically stay on this diet for 4-6 months.

Before Attempting This, Keep This In Mind

It's recommended to do it while under supervision, adhering to the guidelines given in this article.

Also, this diet is not a magic pill. While it may jumpstart results for many, it is not meant to be followed for a lengthy period of time.

Most of our clients start on this diet with incredible results, and once we taper them off to a more moderate diet, they find sticking to a healthy diet easier.

Either way, hopefully, you have another tool in your fat loss tool bel, which will help you further along in your journey.

Onwards and upwards. 🚀

- Dan

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References

1. Nackers LM, Ross KM, Perri MG. The association between rate of initial weight loss and long-term success in obesity treatment: does slow and steady win the race? Int J Behav Med. 2010 Sep;17(3):161-7. doi: 10.1007/s12529-010-9092-y. PMID: 20443094; PMCID: PMC3780395.
2. Tronieri JS, Wadden TA, Chao AM, Pearl RL, Alamuddin N, Berkowitz RI. Early Weight Loss in Behavioral Treatment Predicts Later Rate of Weight Loss and Response to Pharmacotherapy. Ann Behav Med. 2019 Mar 1;53(3):290-295. doi: 10.1093/abm/kay036. PMID: 29800080; PMCID: PMC6374712.
3. Chang J, Kashyap SR. The protein-sparing modified fast for obese patients with type 2 diabetes: what to expect. Cleve Clin J Med. 2014 Sep;81(9):557-65. doi: 10.3949/ccjm.81a.13128. PMID: 25183847.
4. Morton RW, Murphy KT, McKellar SR, Schoenfeld BJ, Henselmans M, Helms E, Aragon AA, Devries MC, Banfield L, Krieger JW, Phillips SM. A systematic review, meta-analysis, and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 2018 Mar;52(6):376-384. doi: 10.1136/bjsports-2017-097608. Epub 2017 Jul 11. Erratum in: Br J Sports Med. 2020 Oct;54(19):e7. doi: 10.1136/bjsports-2017-097608corr1. PMID: 28698222; PMCID: PMC5867436.

Disclaimer: This email is provided for educational and informational purposes only and does not constitute providing medical advice or professional services. The information provided should not be used for diagnosing or treating a health problem or disease, and those seeking personal medical advice should consult with a licensed physician.