Fructose Malabsorption Is Assocated With Low Tryptophan

[gf-soph]

I suspect there are a few people here with fructose malabsorption, I'm pretty sure I'm one of them. Here's some food for thought...

I have been doing some research, and came across a paper called "Fructose malabsorption is associated with decreased plasma tryptophan" (tryptophan is a precursor to serotonin).

It turns out that *women* diagnosed with fructose malabsorption by breath test were found to have lower levels of tryptophan than those who could absorb the dose of fructose. They also had higher scores on a self report measure of depression. This wasn't the case for men. Men have higher levels of tryptophan than women in general (according to cited papers), which may account for the differences.

They concluded that "high intestinal fructose concentration seems to interfere with L-tryptophan metabolism, and it may reduce availability of tryptophan for the biosynthesis of serotonin (5-hydroxytryptamine)." So, the fructose malabsorption is directly causing depletion of tryptophan, possibly by binding to amino acids and proteins in the bowel.

I just thought it was fascinating, I had no idea to this point that it caused anything other than bloating/gas/gi problems.

Thought some of you might find it interesting too

[cassP]

thanku for that- very interesting

FM- check

Depression- check

i feel so much better physically after taking out the major fructose culprits... but still having some trial and error with other fruits & veggies

[Skylark]

Could you please post the full reference? I'd like to read it. Mom has FM and depression and this might help her out!

[gf-soph]

Could you please post the full reference? I'd like to read it. Mom has FM and depression and this might help her out!

Fructose Malabsorption is Associated with Decreased Plasma Tryptophan

M. Ledochowski, B. Widner, C. Murr, B. Sperner-Unterweger & D. Fuchs

Scand J Gastroenterol 2001 (4) p 367-71

The abstract and citing articles are free to view.

[Skylark]

Fructose Malabsorption is Associated with Decreased Plasma Tryptophan

M. Ledochowski, B. Widner, C. Murr, B. Sperner-Unterweger & D. Fuchs

Scand J Gastroenterol 2001 (4) p 367-71

The abstract and citing articles are free to view.

Thanks so much. I have full text access. It's a shame nothing more seems to have been done in the last ten years. There is no clear mechanism for the lower tryptophan in this small cohort, and it's not clear whether adding dietary tryptophan might help Mom.

[gf-soph]

Thanks so much. I have full text access. It's a shame nothing more seems to have been done in the last ten years. There is no clear mechanism for the lower tryptophan in this small cohort, and it's not clear whether adding dietary tryptophan might help Mom.

I know it's not much to guide any real world treatment, but the possibility that the fructose may bind to proteins or animo acides in the intestines is at least interesting.

It's annoying that there isn't any further follow up, you'd think recruiting a sample of fructose malabsobers, testing their blood levels/depression, then getting half to follow a higher tryptophan diet and repeating the tests wouldn't be too hard a follow up.

Did you read some of the related articles? I read over a few, but I wasn't sure if there were any recommendations about adding in more tryptophan, as my depression thankfully lifted a while after going gluten-free.

[Skylark]

I know it's not much to guide any real world treatment, but the possibility that the fructose may bind to proteins or animo acides in the intestines is at least interesting.

It's annoying that there isn't any further follow up, you'd think recruiting a sample of fructose malabsobers, testing their blood levels/depression, then getting half to follow a higher tryptophan diet and repeating the tests wouldn't be too hard a follow up.

Did you read some of the related articles? I read over a few, but I wasn't sure if there were any recommendations about adding in more tryptophan, as my depression thankfully lifted a while after going gluten-free.

I looked at a couple of the other articles too. When that research was published, supplemental tryptophan was banned because of the EMS, and dietary manipulation in a clinical trial long enough to assess depression would be much more involved than just testing blood levels. It's a shame they didn't follow up when the supplements became available again.