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  1. TheRuss is offline
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    Quote Originally Posted by Jack Rusher View Post
    Start at page 257 of this protein delivery textbook, the section on endocytosis as a transport mechanism begins at page 261.


    -- Food Poisoning, Jaffé and Seidl, pg 276.

    ... that some lectins transit to general circulation is not controversial. If you read forward from page 264 you'll get a brief history of the study of lectins, which begins with the discovery of ricin-B (the most toxic lectin known). Aside: as unpleasant as the toxins and antinutrients in grains can be, the ones in certain legumes are much, much worse.
    Yes. For obvious reasons, there's been a lot more out there on the subject of ricin than less, uh, geopolitically significant lectins. Anyways, that satisfies me in that regard.

    Quote Originally Posted by Jack Rusher View Post
    -- Food Poisoning, Jaffé and Seidl, pg 276.

    ... there's much that can be done during preparation to improve the nutritive qualities of grains and legumes, though heat is often not enough. Sprouting is good (lectin content in seeds drops as they sprout). Unsprouted beans should be soaked for 24-48 hours before they're cooked (the combination providing better results than either step in isolation).

    Traditional Food-Processing and Preparation Practices to Enhance the Bioavailability of Micronutrients in Plant-Based Diets
    http://jn.nutrition.org/cgi/content/full/137/4/1097

    In the case of unsprouted wheat, the most useful process is lacto-fermentation (i.e. sourdough lactic acid bacteria hydrolyse gliadin peptides and inhibit their lectin-like behaviour, plus break down mineral-chelating phytates).

    Proteolysis by sourdough lactic acid bacteria: effects on wheat flour protein fractions and gliadin peptides involved in human cereal intolerance
    http://www.ncbi.nlm.nih.gov/pubmed/11823200

    Sourdough bread made from wheat and nontoxic flours and started with selected lactobacilli is tolerated in celiac sprue patients
    http://www.ncbi.nlm.nih.gov/pubmed/14766592

    Amusingly, most of the steps that have turned out to improve mineral availability and reduce toxicity are exactly what your great grandmother would have done by oral tradition.
    I do like me some sourdough.

    Speaking of celiac, it seems to me that the celiac response would be a good first-order approximation (systematic overestimate) of delivered lectins, and so the grocery-shopping decision-making process could be similar. Thoughts?

    Quote Originally Posted by Jack Rusher View Post
    This is more textbook than research paper material, check out:

    Handbook of food science, technology, and engineering, Yui H, Hui, pg 77

    ... for a quick rundown on the hydrolysis index (HI), dextrose equivalent (DE), &c. The Glycemic Index (GI) for most persons turns out to track the HI via a predictable function.
    But there's a catch! Two catches, actually.

    Rate of hydrolysis is a parameter of free glucose available to be absorbed, and free glucose is a parameter of serum glucose response, so it follows that GI and HI would be correlated. That's the good news.

    Bad news #1: Take a look at Fig. 1 of the Goni study. The correlation they're hanging their hat on is total starch hydrolysis percentage at 90 minutes, which is within a hair of the final equilibrium point for all the starches they showed. And given how energetically unfavourable spontaneous condensation back into polysaccharides is, that "equilibrium" is really more of a "completion". So... they rediscovered resistant starch? Ouch.

    Bad news #2: GI is still... problematic. I want to see what other, complementary tools we can come up with for HI, to start quantifying the other variants:

    Quote Originally Posted by Jack Rusher View Post
    Well, obviously. The digestion rate for a given food will vary depending on many factors within the food, within the foods eaten alongside that food (additional fiber, fats, protein, &c) and some qualities unique to the digester (how much of which enzymes he produces).
    (Remember that "obvious" is not a safe assumption. It's obvious to us - at least, I think so - that manufacturers should be dividing dietary fiber into soluble/insoluble on their packaging. This is obviously somewhat less obvious to them.)

    Yes, and also insulin response. The blood glucose curve is the difference between inflow and uptake, and AUC will be reduced by the product (actually integral, but whatever) of uptake magnitude and time. Still linear, but linear with a constant offset... which messes up the ratios to glucose/white bread.

    And, of course, insulin stimulation and sensitivity are a whole other can of worms. Realistically, even if we lump all the digestive tract factors together, we'd still want to measure blood glucose at the portal vein to sidestep uptake altogether - slice the Gordian knot, as it were.

    Quote Originally Posted by Jack Rusher View Post
    You might have more luck for much of what we've been discussing in Google Books.
    I'm starting to get that impression. This whole "Google Books actually being usable" thing is pretty new to me (pretty new in general, I think). It's nice.

    For example:

    Quote Originally Posted by Jack Rusher View Post
    For example:

    The CRC handbook of dietary fiber in human nutrition



    A bowl of oats would provide some insoluble cellulose, but the extracted oat fiber products with which I'm familiar are ~90% soluble.
    Money. This is exactly what I'm looking for. I owe you some push-ups.
    Quote Originally Posted by Emevas View Post
    Downstreet on the flip-flop, timepants.
  2. Jack Rusher is offline
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    Posted On:
    5/10/2009 3:31pm


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    Quote Originally Posted by TheRuss View Post
    I do like me some sourdough.
    Me too. The pain a l'ancienne at the boulangerie around the corner from my old flat in Paris was superb — multigrain, long ferment, wood-fired oven. When I moved to New York I was shocked at the low quality bread people buy in supermarkets here. Fortunately, I've found a couple of decent bakeries since then (though I only use them once in awhile).

    Quote Originally Posted by TheRuss View Post
    it seems to me that the celiac response would be a good first-order approximation (systematic overestimate) of delivered lectins, and so the grocery-shopping decision-making process could be similar. Thoughts?
    Celiac is very wheat specific. Raw tomatoes deliver 0.1% of their lectins to the bloodstream on average in humans (no known toxicity, thankfully), certain legumes as much as 10%, but neither bother celiac patients. In any case, I recommend skipping grains both because sourcing them is such a problem and because even great bread isn't a great food compared to animal protein and green vegetables.

    Quote Originally Posted by TheRuss View Post
    So... they rediscovered resistant starch?
    Not exactly. My take is that HI (and thus GI) is a useful, though imperfect, measure of the upper bound — short of sprinkling extra enzymes on the food — on the rate of sugar absorption from a given foodstuff. Sometimes one needs a back-of-the-envelope number...
    “Most people do not do, but take refuge in theory and talk, thinking that they will become good in this way” -- Aristotle, Nicomachean Ethics, II.4
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    Posted On:
    5/10/2009 5:18pm

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    Quote Originally Posted by Jack Rusher View Post
    Not exactly. My take is that HI (and thus GI) is a useful, though imperfect, measure of the upper bound — short of sprinkling extra enzymes on the food — on the rate of sugar absorption from a given foodstuff. Sometimes one needs a back-of-the-envelope number...
    (Referring to the particular study) It still seems like overkill to me to go to all of that effort to determine the rate of glucose release, only to give up and use the final dextrose percentage.

    If I were running the tests, I'd be curious about two things (well, three, but I'm assuming that the resistant/digestible starch amounts are already known):
    1) Saturation point for the enzyme
    2) The characterization of the curve (the Michaelis constant?)

    From this, we can get all sorts of useful stuff. In particular, given an initial quantity of food (and enzymes), we'd have what you described - maximum rate that the digestive tract could be dumping glucose onto the glucose transporters at a given time. Or we could turn the graph sideways and look at minimum time to deliver a given quantity of sugar.

    But just taking the final percentage is silly.
    Quote Originally Posted by Emevas View Post
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    Posted On:
    5/10/2009 7:48pm

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    Hell yeah! Hell no!
    On a... less academic note, I'm on day seventeen of an Anabolic Diet metabolic shift (<30g net carbs/day, 60/40 calories from fat/protein - daily breakdown is available here). I've been tracking each of these on a morning/evening basis:
    -get up/lie down (wake/sleep approx.)
    -two different BIA scales' readings
    -diameter of my left upper arm, left thigh, and beltline
    -skinfold as per the AccuMeasure instructions
    -body composition photographs: forward and sideways arms-out and arms-down

    Thus far, the verdict on the diet is... nothing's really happened yet. The BIA scales have shown curves to bad and then back to good, the direct measurements are within the margin of error and day-to-day variation, and I'm not really seeing a whole lot from the body composition photos.

    That said, I've learned quite a bit about the process:
    -The scales diverge by about three pounds on average.
    -The cheap BIA scale is convinced that my overnight weight change is water loss.
    -The expensive one is convinced that it's fat loss. (Its muscle mass estimate is surprisingly consistent overnight and throughout the day)
    -When it comes to tripods, you get what you pay for.
    -The compact fluorescent I have in my room takes a while to warm up, and during this period, its brightness and colour vary greatly.
    -Roof-mounted lighting shows more definition (whether or not it's real) than front (flash) lighting.
    -In addition to markings on the floor for the camera and foot positions, put "targets" on the pictured wall to scale and rotate body composition images by.
    -Still don't think I've got posture controlled well enough to be really scientific about the body comp shots. Thinking about leaning against the wall, but that poses its own problems.
    -Skinfolds are tough to take - a bit of variation in finger/caliper positioning introduces a lot of error. I'm thinking I might revise my technique such that the finger positions are more clearly defined (right now I've just got a pair of Sharpie dots to mark the caliper points).
    -I look like absolute Hell first thing in the morning.

    Anyways, I'm not entirely sure what my next step should be. Head's holding up pretty well while I bike to/from work, so I might be able to resume lifting in June, which would be nice. Haven't done a carb load yet, so presumably I'll do one of those next weekend. Not entirely sure about the mechanics of cutting fat.
    Quote Originally Posted by Emevas View Post
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  5. TheRuss is offline
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    Posted On:
    5/12/2009 11:25pm

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    Okay, so I found oat bran at the grocery store today, but of the 10g carbs, only 2g was fiber. I assume it's not the same thing?

    Also, something odd I noticed today - was looking at the bottles of corn syrup, and they claim that although they've got something like 34g carbs/30mL serving, only 11g of that is sugar. Which is absurd, given that the first three ingredients are "glucose, glucose-fructose, water". What the Hell else could there be in it? (And why is fructose there?)
    Quote Originally Posted by Emevas View Post
    Downstreet on the flip-flop, timepants.
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    Posted On:
    5/13/2009 11:35pm

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    So Biochemistry 200 started today. It was a lot of fun. Hopefully I'll be able to keep up a full head of steam for the rest of the class.

    And in case anyone else was wondering, histidine is classified as a positively-charged amino acid because its imidazole group can take on a positive charge at the "double-bonded" nitrogen (forget about Kekule for a while).

    Does anyone (I'm looking at you, Jack Rusher) have any thoughts about dietary fat's effects on insulin sensitivity? A cursory look at a few abstracts makes it sound like there's a relationship with quantity and type. It doesn't really pass my initial smell test, although given that it seems there are really three types of insulin sensitivity (adipose, muscular and hepatic), I suppose it could have a differential effect?
    Quote Originally Posted by Emevas View Post
    Downstreet on the flip-flop, timepants.
  7. Jack Rusher is offline
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    Posted On:
    5/14/2009 7:38pm


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    Quote Originally Posted by TheRuss View Post
    Okay, so I found oat bran at the grocery store today, but of the 10g carbs, only 2g was fiber. I assume it's not the same thing?
    "Oat fiber" is the fiber content of the bran, isolated. I've only seen it in specialized stores and via mailorder.

    Quote Originally Posted by TheRuss View Post
    Does anyone (I'm looking at you, Jack Rusher) have any thoughts about dietary fat's effects on insulin sensitivity?
    Which fats are we talking about? There's a bunch of work, re: omega-3/omega-6 ratios, along these lines:

    http://diabetes.diabetesjournals.org...tract/40/2/280
    http://jn.nutrition.org/cgi/content/abstract/123/3/512
    “Most people do not do, but take refuge in theory and talk, thinking that they will become good in this way” -- Aristotle, Nicomachean Ethics, II.4
  8. TheRuss is offline
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    Posted On:
    5/14/2009 11:58pm

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    Quote Originally Posted by Jack Rusher View Post
    "Oat fiber" is the fiber content of the bran, isolated. I've only seen it in specialized stores and via mailorder.
    Okay, I'm going to try to see if GNC or any of the local health food joints have it. If not, I guess there's this (shipping is liable to be a bitch, though). Do any of the mail-order places you know of ship to Canada?

    Quote Originally Posted by Jack Rusher View Post
    Which fats are we talking about?
    All of 'em.

    The literature I stumbled into was mostly about saturated fats. Actually, it's kind of funny you mentioned omega-3s, because one study I ran into considered saturated, unsaturated and omega-6 but not omega-3. (Will post link if I can find it)

    Good study. From it:

    Furthermore, percentage of long-chain omega-3 fatty acid in phospholipid measured in red quadriceps correlated highly with insulin action in that muscle (r = 0.97).
    Fascinating. And apparently this goes back a ways, too. From an article published in 1987...

    In rats fed high-fat diets, replacement of only 6 percent of the linoleic omega-6 fatty acids from safflower oil with long-chain polyunsaturated omega-3 fatty acids from fish oil prevented the development of insulin resistance. The effect was most pronounced in the liver and skeletal muscle, which have important roles in glucose supply and demand.
    -Storlien, "Fish oil prevents insulin resistance induced by high-fat feeding in rats"

    And I'm not entirely sure what to make of this...

    Fat feeding significantly reduced suppressibility of hepatic glucose output by insulin after both 3 days and 3 wk of diet (P less than 0.01). However, a significant impairment of insulin-mediated peripheral glucose disposal was only present after 3 wk of diet. Further in vivo [3H]-2-deoxyglucose uptake studies supported this finding and demonstrated adipose but not muscle insulin resistance after 3 days of high-fat feeding.
    -Kraegen, "Development of muscle insulin resistance after liver insulin resistance in high-fat-fed rats"

    At present, it appears to me that in terms of body composition, the effects of insulin resistance are not uniform. Insulin resistance in adipose cells (ceteris paribus) should lead to reduced fat storage, whereas insulin resistance in muscle tissue should lead to a reduced nitrogen balance. I'm looking for convincing evidence of asymmetries between them. In plain English, trying to figure out how to stimulate muscle growth without fat growth, or fat loss without muscle loss.

    ---

    I've been getting a fair bit of my dietary fat from walnuts lately - that adds up to a lot of linoleic acid. Might switch to olive oil if I can work out the logistics of it. Not sure I want to start tracking my fatty acid intake more specifically, but at bare minimum, saturated/unsaturated should be doable.

    ---

    Found out today that my biochemistry prof used to be a competitive powerlifter. Nifty, eh?

    ---

    A metric that came up a few times in the T-Nation thread about the Anabolic Diet is waking temperature. Might be worth tracking. What do y'all think?

    (I've also pondered doing a waking heart rate, but I think that one might be too contingent on how jarring my wakeup was...)
    Quote Originally Posted by Emevas View Post
    Downstreet on the flip-flop, timepants.
  9. TheRuss is offline
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    Posted On:
    5/15/2009 12:17am

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    So I've been asked about sleep. Appropriate in two ways:
    -I've spent years of my life with absolutely calamitous sleep patterns, and
    -I should get to sleep pretty soon now, actually

    The vast majority of my approach was psychological/behavioural.

    You have to want to sleep. All the sleep aids in the world won't help you if you're watching "just one more" YouTube video.

    You have to remove obstacles to sleep. Light, distracting sound, drafts, too hot or cold, a rambunctious bedmate... anything that makes the sleep environment the least bit "interesting". This includes your alarm clock.



    Impose discipline in terms of wake times first, rather than sleep times. If you force yourself to go to bed when you're not sleepy, you may wind up laying awake all night. Instead, once you've established that you want to sleep, simply head to bed when your body starts hinting at it, but set an absolutely inviolate time that you will wake up, get out of bed, and stay awake after.

    To avoid ruining your life for the transition period, make only incremental changes to said wake time rather than bumping it up all at once.

    Establish buffer zones for anything that might keep you awake - diuretics, stimulants, gastrointestinally-influential foods (heartburn, bloating, or otherwise), and even water. Get what you need before the cutoff such that you'll have time to completely process it before sleep.

    Melatonin supplementation is great, but do it well before bed. I've heard suggestions of dosing as much as five hours before bedtime, which seems a bit much to me, but taking it right before lights-out hasn't been as effective in my experience.

    Effects of foods may vary. I find that milk protein isolate tends to make me a bit sleepy during the day. I don't know whether taking it just before bed has any real effect, but it certainly hasn't made sleep any harder.

    On a carb-restricted diet, scheduling carbs for the end of the day (for optimally-timed sluggishness) is suggested (IIRC) by both Di Pasquale and Faigin.

    And now I'm off to bed. Hope this helped.
    Quote Originally Posted by Emevas View Post
    Downstreet on the flip-flop, timepants.
  10. Jack Rusher is offline
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    Posted On:
    5/15/2009 12:10pm


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    Quote Originally Posted by TheRuss View Post
    Not sure I want to start tracking my fatty acid intake more specifically, but at bare minimum, saturated/unsaturated should be doable.
    I'm not the least bit convinced that the saturated/unsaturated categorization is useful. My approach is to avoid any vegetable fat that requires an industrial process to produce -- Crisco is about as sensible a human food as motor oil -- preferring olive oil, coconut milk, avocados, &c.

    The best source of long-chain omega-3s is the oily/fatty flesh/eggs/milk fat from animals who've lived on decent feed (example: corn fed cows shift to omega-6s in their fatty acid reserves, just like corn oil fed humans). Sadly, this kind of meat/fish/dairy demands a price premium. Speaking of which, I'm off now to cycle to the farmer's market to buy some... :smile:
    “Most people do not do, but take refuge in theory and talk, thinking that they will become good in this way” -- Aristotle, Nicomachean Ethics, II.4

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