Pho Phatigue

April 6, 2006 12:35 PM

Why does eating Pho make me tired?

I love me a good bowl of Pho. The only problem is that after eating my lovely bowl of noodles, I find myself feeling something like a powerful fatigue. I get a little sweaty and when I get back to work I find my afternoon's productivity is shot.

I'm diabetic and at first though that maybe is was a blood sugar thing, but when I test it at the time, there's no spikes or dips. Ramen and so forth don't do this to me, just Pho.

What is going on here? Would anyone hazard a guess?

posted by Rubber Soul to food & drink (31 comments total)

Could it be the volume of food you are ingesting?
posted by Ogre Lawless at 12:39 PM on April 6, 2006

There's a lot of bleached white flour in pho. Carbo loading always makes me logy.
posted by sid at 12:41 PM on April 6, 2006

Second the post--carb-load crash...
posted by penchant at 12:42 PM on April 6, 2006

The way it was explained to me, if you eat simple carbs or sugar it causes a spike in your blood sugar level. Then you release a hormone that causes your body to remove blood sugar to control the level. It does an efficient job and so the crash.
posted by lunkfish at 12:49 PM on April 6, 2006

Eating large amounts of food will also cause your body to divert blood flow to the gut, that could cause some general wearyness.
posted by blue_beetle at 12:51 PM on April 6, 2006

i feel like hot liquids in general are pretty good at doing that.
posted by soma lkzx at 12:58 PM on April 6, 2006

Could it be from MSG? Monosodium glutamate is a neurotransmitter that gives many people a headache, but there seems to be some anecdotal evidence that some people might react with fatigue. "Anecdotal evidence" = quick Google search of MSG + fatigue = many hokey web pages connecting the two. Anyway, there's a boatload of MSG in many foods, and your pho might be chock full of it. Just a guess ...
posted by Quietgal at 1:01 PM on April 6, 2006

Yeah, there's a lot of carbs in rice, and given the giant piles of rice noodles they put in there it's sometimes deceptive how much you're actually eating. I'd second the carb crash thing.
posted by borkingchikapa at 1:06 PM on April 6, 2006

I agree with quietgal - I have the suspicion it's the MSG. The FDA Backgrounder lists "fatigue" as one of the possible symptoms of MSG consumption. And it's pretty clear there's an unreasonable amount of MSG in Pho.
posted by johnsmith415 at 1:26 PM on April 6, 2006

Mmmm...MSG...
posted by AmbroseChapel at 1:33 PM on April 6, 2006

definitely getting a bit sweaty (do you get mild face flushing too?) could be associated with msg.
posted by gaspode at 1:36 PM on April 6, 2006

>There's a lot of bleached white flour in pho.

I sure hope not. None of the recipes I found online agree with you...
posted by sleslie at 1:36 PM on April 6, 2006

I had a Pho for lunch and I too feel the tired coming down. Was going to have a little nap on the couch in my little hovel of an office.

Damn you, tasty and delicious Vietnamese soup.

The MSG has something to do with it, I think - moreso than the carbs. I sometimes instead grab a ricey stir fry thingy from the food court here and I don't get the crash as bad. However, I also think the crashing is due to soul sucking office work conditions with horrible flourescent lighting. I never get the afternoon crash as bad as I did when I was working down on the cube farm.

Exercise at lunch - even walking - makes a huge difference to alertness and productivity in the afternoon. IMHO.
posted by jimmythefish at 1:45 PM on April 6, 2006

Agree with the carbo-crash replies. High-carb meals with lots of rice or noodles tend to give me an afternoon slump, MSG or none.
posted by brownpau at 1:52 PM on April 6, 2006

I sure hope not. None of the recipes I found online agree with you...
Sorry, a lot of bleached white rice flour in the pho noodles, to be exact.
posted by lemur at 4:21 PM on April 6, 2006

I don't think it's MSG related. I get the same crash from eating a large bowl of homemade noodle soup without any MSG added.
posted by gyc at 5:53 PM on April 6, 2006

It isn't a carb crash, people. The blood-sugar tests rule that out. Telling a diabetic about carb crashes is like telling a narcoleptic about sleep and waking. It's like telling an American about McDonald's. It's like telling Alanis Morissette about whining. I guarantee you Rubber Soul knows carb crashes.

The MSG thing might be worth looking into. Ogre Lawless and blue_beetle may be on to something too, though I doubt it's just a question of bulk. Your gut regulates the pace of digestion through several other hormones, based not only on the bulk of the food but also on its lipid content, protein content, pH, etc., and these can certainly affect how much of your energy gets spent by your gut. In my case, a lot of red meat will bog me down a good deal more than any carbohydrates. Try your pho with/without meat, with/without a lot of vegetable fiber, etc. and see if it changes anything.
posted by eritain at 6:16 PM on April 6, 2006

Pho related question... How is it pronounced? I'd order it more if I weren't embarrassed about saying it wrong.
posted by Jazz Hands at 6:18 PM on April 6, 2006

According to the proprietors of the Vietnamese restaurant at which I am a shameless regular, it's "Fuh". Kind of like "What the fuh?" (but not quite the same vowel).
posted by Emperor SnooKloze at 6:31 PM on April 6, 2006

Pho does this to me, too. I always assumed it was all the fat in the noodles causing release of cholecystokinin and vasoactive intestinal peptide.

But really, who knows?
posted by ikkyu2 at 6:55 PM on April 6, 2006 [1 favorite]

If MSG is so bad for you, why doesn't everyone in Asia have a headache?
posted by TedW at 7:05 PM on April 6, 2006

pho shizzle!
posted by Alt F4 at 7:55 PM on April 6, 2006

How come two of results for searching pubmed on "the itis" have to do with sawing off your hand? I didn't know the luther burger was so dangerous.

The first result debunks what I always thought was the reason for the itis; that bloodflow was being diverted to your stomach. But I guess perfustion of the brain has got to be close to constant under normal conditions, otherwise you'd have a mini-stroke every time you ate a couple of taco bell chalupas.

I dunno what's in pho, but maybe it's a turkey-like tryptophan effect. i.e. you eat, insulin transports amino acids (like yummy glutamic acid) across cell membranes--but it does not have that effect on tryptophan. So there's more tryptophan (if that's what's in pho noodles) to cross the blood brain barrier & get converted to serotonin. And then it's happy nappy time.
posted by neda at 9:32 PM on April 6, 2006

Hey folks, thanks for all the input.

After reading your responses and then doing a bit of other research, I'm pretty sure it's not a case of carb crashing. Ever since being diagnosed with diabetes, I've become far more of an expert on carbs than I ever though I would like. I check my blood sugar regularly and have a pretty good sense of the foods that I eat.

I hadn't thought about the MSG angle, though. I'll have to expore that one a little more in depth. I'm glad to hear that I'm not the only one out there to get all sleepy after a lovely bowl of pho.
posted by Rubber Soul at 9:38 PM on April 6, 2006

Here is an article to offer regarding the supposed MSG "effect". Since you're exploring it a bit more, I found this an interesting read and you might too.

I've never experienced this with Pho, thankfully. Mmm, pho.
posted by freudianslipper at 11:17 PM on April 6, 2006

Pho also typically doesn't have much fat. Doesn't eating fat with your carbs help regulate its uptake into the blood?
posted by lemur at 2:01 PM on April 7, 2006

Pho also typically doesn't have much fat.

I don't believe that for a minute. Those noodles are something like 30% fat by dry weight.

I've noticed the phonomenon described, but I don't know what causes it. I always assumed it was a side effect of an endocrine response to fat intake.
posted by ikkyu2 at 3:14 PM on April 7, 2006

ikkyu2 - really? Is there fat in the rice flour? interesting!
posted by lemur at 10:47 PM on April 7, 2006

Rice flour isn't like durum - if there weren't other stuff in it, it wouldn't make a noodle.

Maruchan Top Ramen noodles are 29% fat by dry weight according to the label, and I can't see that pho noodles are significantly different.
posted by ikkyu2 at 11:57 PM on April 8, 2006

As many as 1 in 5 Type I diabetics apparently have celiac disease, though most are undiagnosed. Eating even small amounts of wheat will give some cd sufferers the symtoms you describe, among others.

Even if the noodles in your Pho contain no wheat, if you have cd, you may be reacting to MSG as if it were wheat. Gliaden, the protein in wheat to which people with cd are sensitive, contains up to 43% Glutamine.

There is now a widely available blood antibody test for celiac disease.
posted by jamjam at 3:55 PM on May 12, 2006

Correction: as many as 1 in 20 Type I diabetics apparently have celiac disease.
posted by jamjam at 4:46 PM on May 12, 2006