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Phenylalanine and diet soda - good times!

Mr. Cat

Senior Member
Messages
156
Location
Nothern California
So for the past few years, I have noticed that if I drink decaffeinated diet soda (caffeine can make me crash), I will experience more mind clarity and alertness, with no side effects and no crashing. It won't get me out of a deep crash, but if I am mildly tired and foggy, it will pick me up. Who knew? The mystery ingredient? I believe it to be Phenylalanine, found in the sweetener aspartame, though it could be something else associated with the aspartame. I am sure those of you more schooled in biochemistry could explain why this is so, or why some of us may be deficient in this amino acid. For me, though, it is just another (inexpensive!) weapon in my growing arsenal of supplements to ward off fatigue. I don't drink more than a small glass or two at a time, and it wears off in less than an hour.

Of course you shouldn't ingest phenylalanine if you have the genetic disorder phenylketoneuria (PKU), that is unless you like having seizures, brain damage and mental retardation. Of course, if you have PKU, you'd probably know it by now, as it seems pretty unforgiving, kind of like another 3-letter acronym I can think of.
http://www.mayoclinic.com/health/phenylalanine/AN01552

I'm sure this is just one more of those things that works for some CFS/ME subsets and not others. Anyone have a similar experience?
 

Mr. Cat

Senior Member
Messages
156
Location
Nothern California
An update: I've actually changed my tune on aspartame after some research. It seems the reason why aspartame is so disliked is because it is classified as an excitotoxin, meaning it excites brain cells, but in the process kills them. Though I've only had good effects from diet soda and no negative side effects, all those good effects I was having could have been the result of brain cells dying (or not). My brain is fragile enough as it is, so I decided to get off diet soda. I tried a phenylalanine supplement, but it just wasn't the same. Diet soda - goodbye, old friend!
 

Tammy

Senior Member
Messages
2,167
Location
New Mexico
If your thyroid tests are fine it is not your thyroid. I am looking at the pathway; phenylalanine is turned into tyrosine (which helps the thyroid) and then into l-dopa which supplies us with dopamine, norepinehrine and epinephrine.

I think you probably have fast MAO and COMT genes that make you break down dopamine, norepinehrine and epinephrine too quickly. That is my guess.

Do you feel better when you eat a lot of red meat?
Havn't noticed or paid attention but sometimes I do feel like I crave it.