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Should You Use BCAAS During Ketosis & Fasting? (Definitive Answer) - Physique Formula

Should You Use BCAAS During Ketosis & Fasting? (Definitive Answer)

by James Smith June 29, 2017

Should You Use BCAAS During Ketosis & Fasting? (Definitive Answer)

BCAA, Ketosis And Fasting

I was recently sent a link to a video addressing the topic of if you should use branched chain amino acids during a fast and if doing so, will kick you out of ketosis.

I’m happy I was sent that video as it’s a topic I’ve been meaning to address. In summary of the video, the author states, and I’m paraphrasing,

“Leucine causes a HUGE spike in insulin”.

Later in the video he says....

“A subject who was fasting for 50 days was given an injection of glucose and the subject was almost instantly kicked out of ketosis”.

These two BIG swings and misses bring the author of the video to his final point that
“BCAAs kick you out of ketosis and fasting and you don’t need to have BCAAs during a fast”.

Where to begin, where to begin.....

You can watch me talk about this topic in a video below.


You can listen to my podcast about it right here


Branched Chain Amino Acids & Fasting

I appreciate anyone trying to build a business or brand but doing it was incorrect information and perpetuating lies to fulfill some personal agenda is terrible, there I said it. Let's move on.

Starting with the loosely thrown around summary of studies.

You can’t just say that BCAAS or any supplement or food causes a HUGE this or a LARGE that.

What are we comparing the objective to?

Chocolate milk increases muscle protein synthesis when compared to sugar.

The media picks up on the chocolate milk study years ago and no one ever bothers to look into what the comparison was.

When you want to examine protein synthesis what do YOU think would work better?

Something with protein (chocolate milk) versus something with no protein (sugar).

Take a wild stab…

Video Point 1:Leucine causes a HUGE increase in insulin levels.

It's perfectly reasonable to think that you. the consumer, may hear the word HUGE or LARGE and subconsciously think that the author is making a factual point.

Except he wasn’t.

What was the insulin response HUGE compared to? No insulin response?

Wouldn’t any, normal tiny insulin response actually be defined as HUGE then?

The author fails on statement one.

Video Point 2: Since a man who was fasted for 50 days was given an injection of glucose solution and the glucose kicked him out of ketosis then BCAA powder supplements can do the same thing and should be avoided.


Comical at best.

Children eat ice cream in the summer, more children drown in the summer. Therefore eating ice cream causes drowning.

Absurd, right? Well that’s identical to the statement that the author of the video was making.

Now I did a quick pubmed search to find any peer reviewed study done at a reputable university showing a 50 day fasting trial.

I could find one. I have no idea where the author found this study but I can’t think of a reputable lab that would actually have someone fast for 50 days.


Either way, let’s assume that study was done and is real.

Giving someone a direct, IV drip, of glucose is dramatically different than giving them 1 scoop or 50 scoops of BCAA powder.

Uhhh..continually IV glucose drip versus BCAA supplements.

How is there even a remote connection?

There is none

The author fails on statement two

The Reality Behind BCAAs, Fasting and Ketosis.

Yes, I do run a supplement company who’s #1 selling product is an all natural BCAA. How’s that for full disclosure?

Let’s look at the FACTS of the case.

1) Any amino acid amount, even the tiniest bit, will kick you out of autophagy, the main goal of fasting.

If you aren’t familiar with autophagy, it’s the cleaning out of your cells to remove the “bad” parts.

But what’s the goal of fasting? Ask yourself, everyone fasts differently but please don’t let it be “because the internet said so.”

And just because you’re out of autophagy doesn’t mean you still can’t fast.

Remember, the majority of studies done on “fasting” are done on long term caloric restriction.

You are still restricting calories even if you have a BCAA supplement, especially The Physique Formula BCAAS which are carbohydrate, fat, calorie and sugar free.

You’d still get 99% of the benefits of fasting if all you had was some BCAAS in water.

This is yet another example of stepping over dollars to pick up dimes.

So it’s not just BCAAs, the 2 grams of protein in your morning coconut milk will still kick you out of fasting.

2) Leucine, BCAAS and Insulin

Let me be very, very clear. The author of this video has NO clue what he’s talking about and has done no research.

Leucine and ALL amino acids do cause an INSULIN spike but it is a SINGLE phase response.

Carbohydrates like bread or potatoes cause a BI or Double phase response.

Single versus double, we all know what is worse.

This paper from 2011 sums everything up nicely

“The ingestion of BCAAs temporarily increased plasma insulin levels and affected plasma concentrations of FFAs, but had almost no effect on glucose or urea nitrogen”


The insulin response from BCAAs is short term, in and out of your body. If you were to eat a piece of bread, the insulin response is BOTH short and long term causing the pancreas to get involved and raise blood glucose to bring insulin back to normal.

Insulin levels increasing is a normal,daily activity that happens when you're just sitting still on the couch.

Or even as insulin levels spike when you wake up in the morning.

Or when someone cuts you off in traffic.

Should my next article examine if waking up kicks you out of ketosis or fasting?

Of course not because transient, short term, increases in insulin do NOT kick you out of ketosis because once you officially enter ketosis you’ve built up some equity.

There’s “space” between ketosis and glycogen based energy pathways.

It’s not some on-off switch once you’re actually in ketosis.

And once you’re in ketosis you don’t just stay at the entrance.

Like a night club, you go deeper and deeper onto the dance floor, if you want.

As the days go by and you continually follow the same dietary habits that brought you into ketosis they will bring you DEEPER into ketosis.

Furthermore, we are talking about exercising individuals here, right?

Muscle mass, activity level, body fat and lean mass are all also factors.

Well some amino acids can actually be converted to KETONES to further ketosis, though not significantly.

There’s been reported cases of individuals eating upwards of 300 grams of protein a day and STAYING in ketosis.

3) Losing muscle during fasting

The author of this video also talked about the fear of losing muscle during a fast.

So which one is it, are we in ketosis or fasting? He still hasn’t made up his mind.

Oh, we’re ketogenic fasting. Because if one diet doesn’t work wonders then we should combine TWO types of diets.

The author states that your body produces, 30 or 40 or 50% of amino acids during a fast.

There’s only TWO ways that your body can produce amino acids

1) We can eat them, which in this case we aren’t.
2) Our body can break down muscle tissue for amino acids, which is what’s happening here.

I’m not sounding any alarm though. Fasting, even if you take a scoop of BCAAS at the start the day, has tremendous benefits on anabolic hormones so you won’t burn muscle tissue.

Let’s wrap this up.

1) The author of this video is completely wrong and just made a video with clickbait headlines that’ll get a bunch of views because he was once a bodybuilder. Remember, abs, ass and boobs equals social views these days.

2) Why are you fasting or in ketosis? Both have benefits but ask yourself why.

3) In the case of fasting, you really shouldn’t fast more than once or twice during the week if you’re a hard charging individual. If you do fast once or twice a week for a few hours, don’t crush yourself over the fact that you didn’t have protein. It’s not the end of you.

4) BCAAS have a quick rise in insulin but it is WITHOUT the corresponding rise in glucose. As a result, you don’t store body fat, you actually shut off catabolic hormones and create a healthier. more anabolic environment.

James Smith
James Smith


That's me, Jimmy Smith and this is my website and the Physique Formula is my brand and it's 100% all natural and artificial sweetener free

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