The HARDEST diet for Fat Loss (and what you should do instead!)

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The PSMF diet works, but it is so hard!

I got lean.  Quickly.  But I would not recommend this diet for the majority of people!

I am always learning, and I love trying and testing new things when it comes to training and nutrition. Which is why I was all too happy to try this dieting approach on myself.  I had seen my body fat levels creeping up lately.  So, I was quite keen to diet down anyway.  Which is why I figured why not test out a different dieting approach.


“Protein Sparing Modified Fast” (PSMF)

The dieting method I used was based on a “Protein Sparing Modified Fast” (PSMF).  Basically, this involved eating a fairly high protein diet, but minimalizing carbohydrates and dietary fats by as much as possible.  And of course, my overall calorie intake was in a deficit.

So, the theory is that the high protein intake will help spare muscle mass.  While the calorie deficit, combined with the fact that the body would only have body fat stores (plus a little excess dietary protein) for energy, would theoretically result in rapid fat loss.

Also, there would be the benefit of protein having a high TEF rate (thermic effect of food), meaning a fair number of calories from protein are used up through digestion.  And protein tends to be more satiating, which theoretically would make it easier to eat less food.

What I ate

I followed this diet for 6 weeks.  My calories were approximately 1,500 calories a day.

My daily macros fluctuated a bit but were roughly:

250g of protein

30-40g of carbs

30-40g of fats

I didn’t directly eat carbs or fats, but these accumulated from the lean protein sources and cruciferous vegetables I ate.  These included a lot of whey protein powder, chicken breast, cottage cheese, egg whites, broccoli, and cabbage.


What happened

At the start of the diet I weighed 80kg.

At the end of the 6 weeks I weighed 73.5kg.

So, I lost 6.5kg (about 14lbs) in 6 weeks.

But, I’m sure that I lost muscle too.

Not to mention losing all of my energy along with it!

Everything became a struggle.  I felt tired all of the time.

I wore a Fitbit and I ensured that I continued to get 15,000 steps a day.  But just walking felt like a workout!

My gym sessions got shorter and shorter and less and less frequent.  Any cardio besides walking felt impossible.  And my weight training strength dropped embarrassingly low.

But yeah, I did get ripped pretty quickly.  And to be fair, I didn’t really feel hungry much, considering that I filled up on lean protein and green vegetables.


The problems…

When your body doesn’t have carbs OR dietary fats to use for fuel, it sucks!  I felt weak, had poor energy levels, and lost some muscle.

Unless you are significantly overweight / obese, you should probably only use a PSMF type diet for very short durations of time (e.g. 2 weeks).

Expect energy levels and physical performance to go down the toilet on a diet like this.

Get used to eating the same foods over and over since your food choices are so limited.  Though to be fair, hunger was rarely an issue.

Why I do NOT recommend this diet!

OK, to cut to the chase, this diet is simply NOT sustainable!  It’s too hard!  And when adherence is the main factor in the success of any fat loss diet, I just don’t see many people being able to stick to this!

I mentioned above that unless you are significantly overweight, I don’t think you should be doing this diet for more than 2 weeks maximum.  And that’s because it is simply too difficult to follow long term.  It is very restrictive and limited in food choices. It saps your energy, plus I feel I lost too much muscle on this diet.

Also, I’m sure that there would be a high risk of nutrient deficiencies if you were to diet this way for the longer term, due to such limited food sources.

You could maybe use a PSMF diet like this for the first 2 weeks of a fat loss phase.  After the 2 weeks, you would transition into a more balanced and less restrictive fat loss diet.  BUT…I don’t see this working well for most people!  I can imagine most people would rebound coming off such a restrictive diet like this – i.e. they would diet for 2 weeks and then binge and pile the weight back on!

flexible eating

What is an easier way to diet for fat loss?  Keep an eye out for “The Doughnut Diet” FREE 7 Day Challenge!

I recommend that people diet in a way that isn’t so restrictive, so that you can continue to follow it for the long term.

I’d say to go with a realistic healthy, full and balanced diet, that doesn’t involve cutting out ANY food groups – and that includes junk food too!  This is the real key to sustainable, maintainable, permanent fat loss.

And it just so happens, that I will be running a FREE 7 day challenge, in which I will teach you the flexible dieting system that I use to achieve a lean muscular physique, while still getting to eat your favourite junk food!

So, check out “The Doughnut Diet” – my Free 7 Day Flexible Eating Challenge.

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