I am wondering about the science behind whether taking a BCAA supplement or other amino acids “breaks” a fast? So, for example, I like to do a daily fast of about 16 to 18 hours, and I like to work out fasted in the morning. However, I find a get a boost of energy and in performance if I do some BCAA’s or full spectrum amino acids beforehand. Is this halting the fast and preventing the benefits such as autophagy from taking place? I am really lean and my performance flags sometimes because I don’t have much body fat to draw energy from. But I would hate for these supplements to impact the fasting benefits.
Fasting and amino acids
My “gut” reaction is that BCAAs would break both the decreased insulin and autophagy associated with a fast, but have no science to support it, so I’ll be monitoring this thread closely since I would also like to know.
I know fat does not disrupt the fast, but since BCAAs are a type of protein, which does disrupt the fast to a degree, I’m wondering how they compare to actually ingesting meat or animal protein. I take about 3 g along with some Keto cana, and exogenous ketone, and I can power through a tough workout without taking in any food beforehand. I consider it to be a semi fasted state since I do take in some calories from the ketone supplement. But I feel like there are still benefits to engaging in a workout with these additions.
My understanding is that amino acids (BCAA’s, and in particular leucine) cause a release of insulin.
The BCAA leucine is the amino acid most inhibitory of autophagy. So it could shut down one of the processes you are trying to engage by fasting.
Bingo!! I wonder if it’s an issue of scale. My bcaa supplement has 2.5 g of leucine. Can that really disrupt the autophagy process and cause an insulin response?
I don’t know how much would be needed and for how long autophagy would be inhibited.
That report is incredibly dense…I can’t sort through the language!
Doing some research there are opposing views on this subject, and I think there are definitely some exceptions that affect whether the bcaas have a negative effect on fasting. Some feedback supports the idea that the small amount of amino acids in a low dose do not affect the process of fasting in a significantly detrimental way. Others say they will cause an insulin spike but do not specify at what dose this occurs. If you are very lean, you risk muscle loss during a fasted workout is the thought. Would I be able to detect an insulin response to the aminos by measuring my BG after ingesting them?
This isn’t an answer to your question, but you might find it interesting.
I am currently listening to Ben Greenfield’s podcast episode from Jan 18, 2017. He is talking to Dominic D’Agostino and it is titled Which Ketone Supplement Works Best.
At ~33 minutes in, they are discussing BCAA’s and fasting.
At the beginning of the podcast, he does suggest getting your Propeller Hat on for the nerdiness. hahahaha
That is hilarious…I posted a link to that episode in “Show me the science”. It was excellent
oops! I’m sorry I haven’t been on as much as usual the last few days. I am way far behind…64 new topics I haven’t even looked at!