ABSTRACT
Beginning with this issue, we present answers to practical questions regarding autophagy from the lay public.
The question
[I am] a layman trying to learn about autophagy for health reasons.
My question is on the role of leucine in stopping autophagy. (“Stopping it cold” is how one article put it.) I am trying longer fasts–5 days plus–to promote autophagy. Coffee keeps me going during these times, but I am not a fan of black coffee. I have read stevia could possibly stop autophagy (as it leads to releasing insulin) but then read on the Medium website that those studies were conducted with subjects who were also taking carbohydrates in, while they were taking the stevia. In short, the article claimed that if you are already glycogen depleted, coffee with stevia will not release insulin, thus shouldn’t knock you out of autophagy.
The challenge is this: of all the stevia I could have bought, I ended up buying some stevia, that for some reason I can’t fathom, has leucine, of all things. Not sure how much, but as they are tablets (with sodium bicarbonate to make them dissolve) I can’t imagine it’s too much.
Still, I recalled Dr Meijer’s study, (and subsequent articles about leucine ‘stopping autophagy cold”) and I hate to mess up the benefits of autophagy, due to a little stevia. However, that stevia is making me much more compliant as to fasting (be it extended fast, or Intermittent Fasting.)
Do you know if the minuscule amount of leucine (that I imagine in this stevia) would “stop autophagy cold”? Or could you forward this to Dr Meijer to see if he would know?
If you are curious [as] to why I don’t just [buy] another brand, I am an expat working in Africa, and had to rely on a fellow expat who traveled abroad to bring this stevia back for me, so it’s the only realistic option at this point.
Any help you or Dr. Meijer could give would be greatly appreciated.
Sincerely,
Andrew
The answer
In answer to your question I do not think that the small amount of leucine present in your stevia preparation is sufficient to interfere with autophagy. There is already a substantial amount of leucine present in blood and cells in your body, and the small amount of leucine in the stevia will not have much of an effect. Another comment is that 5 days of fasting is too long for activating autophagy. The greatest acceleration of autophagy takes place after 24–48 h of fasting. During prolonged fasting autophagy declines again because proteins, many of which are enzymes essential for survival of the cells in our body, need to be spared. The brain, which normally uses glucose as a fuel in the fed state, obtains glucose from glycogen during the first period of fasting; this is followed by glucose produced from amino acids (derived from protein degradation by autophagy). After long-term fasting the brain also uses ketone bodies as an energy source; these ketone bodies are products of the breakdown of fat in the liver. In this way, during long-term fasting, proteins can be spared and autophagy declines.
I hope this information will be of help.
Best regards,
Alfred J. Meijer