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BCAA vs Fat Burning Supplementation During Fat Loss Phases

Hi CT. I am about to start a cut where I will be using the UD2.0 by Lyle Mcdonald as a starting diet because I like variety in terms of my Diet plan. However, I was wondering if a fat burning supplement is worth it, especially the ones who contain forskolin and I know that TC Luoma is a huge advocate of forskolin or I am better spending my money on extra BCAAs to favor muscle retention. Also, the fat burner I plan to buy has about 50 mg of yohimbine which is a good for blood flow and burning stubborn bodyfat which is my main issue.
Ps: I also have access to salbutamol as the main fat burner but I won’t discuss that here.

Ok first and foremost: if you follow a non-idiotic diet with sufficient proteins (UD2.0 is solid) and are training hard, your chances of losing muscle are very slim until you drop down below a REAL 10% where your chances of losing some muscle increase, but it still is not extremely likely.

You will FEEL like you are losing muscle: your will feel smaller in your clothers, your muscles will feel softer, less swollen at times. These will give you the perception that you are losing muscle.

Heck, your strength on some exercises (mostly big compound pressing movements) might go down a bit. But this is not a sign that you are losing muscle, but rather that your joints are less “packed” because of a loss of water and fat and that can make your joints less stable, as a result the body protects itself by not allowing you to use all your strength potential.

Those who lose muscle when dieting down commit one of these mistakes (or are in a situation where some of these things can occur):

  1. They diet like idiots… the famous low carbs AND low fat diet. Basically eating 800-1000 calories a day only from protein.

  2. They don’t train hard (or they don’t train at all)

  3. They have a stressful lifestyle which brings their cortisol through the roof all day

  4. They work a VERY physical job

That having been said, here is my view on BCAAs and fat burners.

FAT BURNERS: don’t use them until they are truely needed. A big mistake isusing fat burners from the start of the diet. At the beginning of your diet far will drop down fairly easily and a fat burner might not speed up the process that much. It is better left for the last few weeks of dieting, when progress is much harder (both because of adaptations and because you have much less fat left to lose). If you take fat burners from the start, you kinda have to take them until the end otherwise your progress might slow down or stall. BUT fat burners, especially those that work by binding to the beta adrenergic receptors (stimulants) have tons of side effects and taking them for a long time is a bad idea.

Especially products like albuterol, clenbuterol, salbutamol, DMAA, ephedrine, synephrine and the likes. These, on top of their effect on blood pressure (which is the no.1 cause of help problems down the road for bodybuilders) and other cardiovascular impact, can cause adrenergic receptor desensitization. If you want to feel like shit this is one of the best things you can do! When that happens you won’t respond to your own adrenaline and you will feel unmotivated, depressed, no energy, no drive, etc. This is what happens when you take the stimulants mentionned above for some time then stop.

As for BCAAs, even though I was one to recommend them in the past. And I do think there is SOME value to BCAAs (especially leucine) to increase mTOR activation from the workout. It is grossly overrated as a supplement and I don’t think it will do that much to prevent muscle loss on a diet. It might have a small effect, but it could lead to other issues.

The BCAAs can increase insulin production. When insulin is elevated you are less efficient at mobilizing fat (you are still mobilizing it, but less efficienctly). The less insulin sensitive you are, the more likely you are to produce insulin in response to ingesting BCAAs.

Another issue is that if you spike insulin and the only thing in your blood are BCAAs you will likely cause a drop in blood sugar (I once when into hypoglycemia from ingesting leucine on an empty stomach). That drop in blood sugar, on top of making you feel like crap, will give you sugar cravings, which isn’t great while dieting down.

On last point is that low blood sugar lead to the release of cortisol.Why? Because cortisol is n hyperglycemic hormone: one of it’sfunction is to increase blood sugar levels when it drops down too much. So if you constantly put yourself in a state of low blood sugar chances are that cortisol levels will be chronically elevated, which could actually make it harder to preserve muscle mass.

BCAAs could have a small benefit taken pre-workout to increase mTOR activation, but you would do the same from a moderate dose of the right carbs or protein (PLAZMA for example) pre-workout. And taking BCAAs throughout the day to try to minimize muscle loss is also something I don’t recommend anymore.


Thank you so much for your answer CT. To think that you put all that time to answer a fan question is overwhelming. Thank you so much for your help!

Pretty awesome that you will give that much effort in responding to his question! Way to pay it forward man

Only person in the entire industry to do that is CT. He is one of the most knowledgeable and humble coaches out there, yet he is always ready to help regular folks like us achieve their goals.


I’m only doing it for the fame and admiration