Saturday, January 12, 2013

Saturated Fat & Postprandial Endotoxemia. Caffeine & Max. vs. Submaximal Exercise. Lactoferrin & the Battle Against Visceral Obesity. High Intensity Strength Training, Free Testosterone & the Use of Perceived Recovery Scales

Gram negative bacteria, as these E. coli bacteria which have been photographed with a low-temperature electron micrograph (magn. x10,000) tend to produce endotoxins in your gut, while gram positive bacteria tend to produce exotoxins on your food - nasty, ha?
It has been estimated that a single cell of Escherichia coli contains approximately 106 Lipid A or endotoxin molecules with a mass of about 100,000 Da (the exact mass varies according to the LPS type). The typical human intestinal tract can harbor approximately one gram of endotoxin, which is ~2-4x more than what scientists used in previous rodent studies as a "lethal dose" (Kawai. 1991). Aside from the information about the lethal dose of endotoxins in rodents, these figures, which are at the same time the SuppVersity figures of the week are part of the study by Mani et al. with which we are going to kick off this week's installment of On Short Notice. I guess these figures give you an idea of the toxic potential within your gut and why all the hoopla about leaky guts, the human microbiome, pro- and prebiotics, endotoxemia and co. is probably not all hype, but a hitherto largely neglected aspect of human health (and disease)

Saturated fat < > gut interaction sheds a dark shadow on the "benign fat of our ancestors"

(Mani. 2013) -- According to a study from the University of Iowa, the endotoxemia response to a meal, i.e. the amount of inflammatory innately produced toxins from your gut that enter circulation in the postprandial phase, is increased in response to a meal that's high in saturated fat.
Figure 1: Endotoxin permeablity and changes in serum endotoxin levels in the hours subsequent to the ingestion of a test meal containing either 50ml  coconut (CO), vegetable (VO) and fish oil (FO) in otherwise healthy pigs (Mani. 2013).
The scientists also found that omega-3 fatty acids from fish and cod liver oil reduced the amount of endotoxins hitting the blood stream and that olive, as well as vegetable oils exhibited a neutral effect. As the data in figure 1 (left) goes to show you, the underlying mechanism behind the saturated fat induced influx of toxins was a whopping +60% increase in the endotoxin permeability (Papp) of the guts of the 24 pigs on which the experiments have been conducted.

Click here to read more about a previous study that shed some light on the effects of certain nutrients on the gut microbiome.
Now you can certainly argue that the ground corn-soybean meal dough that was at the base of the test-meal was "the devil" here, but let's be honest, for the average Jane and Joe, there are similar "devils" in any standard meal, they consume, so that the finding that the addition of 50 ml fish oil (FO), vegetable oil (VO) or coconut oil (CO) made such a difference in terms of the influx of pro-inflammatory endotoxins is nothing you can simply ignore. The same goes for the fact these effects occurred in response to the ingestion of organic coconut oil (according to the researchers purchased from Spectrum Naturals Inc.), is actually somewhat unsettling and certainly not in line with some of the previously established benefits of coconut oil consumption, such as it's waist reducing effects in overweight subjects (click here to learn more).

What's also interesting is that previous rodent studies yielded different results. Laugerette et al., for example, found a similar increase as Mani et al. in mice, but in response to canola and sunflower oil (Laugerette. 2012). This raises the question in how far the effects may be mediated by the baseline diet and the corresponding bacterial composition of the small and large intestine (or species specific effects?). After all, the gram negative bacteria of which scientists believe that they increase in response to high fat diets have the highest endotoxin content. They populate the distal ileum and the colon and are supposedly the main sources for circulating endotoxin (Berg. 1999) - if you had less of them to begin with, you are not as likely to suffer from an acute influx of endotoxins in response to the ingestion of SFAs. Moreover, what it the endotoxins were released in response to the antimicrobial effects of coconut oil?
Update: Wyatt Brown left an interesting comment on this issue on the SuppVersity facebook wall, I do not want to deny anyone, so I thought I'd just update the post with it:
I'm glad people are talking about the endotoxemia thing, that's what we do at SuppVersity, have the discussions nobody else does! I think it's important to recognize that, especially for the paleo/ancestral types who accuse grains of inducing intestinal permeability and then go and eat diets that cause intestinal permeability...and because endotoxemia is bad...

But I don't think that all is lost, the evolutionary argument may just need to be modified a little. The current paradigm involves looking at individual foods, or worse yet (though that was supposed to be an improvement) broad classes of macronutrients, and our adaptation to them. Well, it looks like those might have been wrong in some ways, maybe we aren't fully adapted to some foods, but then again maybe we are adapted to a particular kind of diet that makes those foods all right.

Some of the antioxidants in orange juice prevent intestinal permeability from dietary fats it seems the bile acids secreted during digestion are to blame, and it's an oxidative mechanism, so the orange juice prevents this (Ghanim. 2010). It also works with grape polyphenols (Ghanim. 2011).

Moreover, it seems that feeding mice a diet rich in fermentable fibers prevents endotoxemia - maybe due to butyrate production and its protective effects on intestinal cells (Cani. 2007). And acutely, fiber with a high fat meal also prevents the effect (Ghanim. 2012). It's probably due its ability to sequester excess bile acids (Vahouny. 1980)

So it would appear that we are adapted to a diet containing those fats but also containing fruit and fiber.
As you see, Wyatt makes a pretty valid point, when he hints at other contributing factors of which I know that they got forgotten way too often in the paradigmatic and downright stupid and unproductive high fat vs. low fat and the SFA vs. PUFA skirmishes on the Internet.
I guess, there is still much to learn here and I hope you are aware that the SuppVersity is the place you can do just that: Learn something new everyday!

Caffeine's effect on muscular fatigability during maximal vs. supramaximal stimulation

There is no question that caffeine can have beneficial effects on exercise performance - whether every athlete benefits to a similar degree is yet as questionable as the "ideal" dosage to elicit optimal fat loss effects without the negative side effects that are associated with the chronic overconsumption of any type of stimulant (click here to learn more about the narrow margin between "just enough" and "already too much")
(Tallis. 2013) -- In a very straight forward in vitro experiment, researchers from the Coventry University in the UK found that the ergogenic effects of caffeine depend on the intensity of the muscular contractions. When the scientists exposed isolated soleus muscles to up to 70µM of caffeine (that's still within what you would consider a "physiological dosis"), Tallis et al. observed that the muscular endurance increased only, when the muscles were challenged at submaximal intensities (+19.2%), while it decreased by 17.6% upon maximal challenge.

Whether or not this is important for the average strength trainee remains questionable. After all the "endurance" part of your regimen is usually conducted at submaximal intensities and weheter you can do one interval more or less probably doesn't matter as well. For a professional cyclist participating in a time trial, those 17.6% may well make the difference between victory and defeat. On the other hand, there is more to "endurance" than local muscular fatique, so that caffeines effects on the central nervous system will at least ameliorate, if not totally counter these potential downsides.

Lactoferrin, an overlooked visceral fat annihilator?

I don't even know if all of you are familiar with the globular glycoprotein lactoferrin that is widely represented in various secretory fluids, saliva, tears, nasal secretions and - above all - colostrum. It has a very important role in the immune defenses of your body and according to a recent review by Japanese scientists, it does also exert direct lipolytic (breakdown and release of fat from) and anti-adipogenic effects in vitro and in vivo.

All of you who read the "Ask Dr. Andro" installment on Milk & Colostrum should at least have heard of lactoferrin before. It's one of the anti-microbial, anti-fungal and immune modulating molecules in the white elixir of mammalian life that's also suppose to exert antagonist effects on the opioid receptors (read more).
A hitherto still unsolved problem is the delivery of the lactoferrin to the target tissue, but with the advent of specifically enteric coated lactoferrin which circumvents the breakdown of the 80kDa protein in the acidic milieu of the stomach and allows its passage via the lymphatic system into the mesenteric (visceral) fat pad, where it accumulates, interacts with the lactoferrin receptor LRP1 which is directly located on the adipocytes of the visceral adipocytes and suppresses the expression of PPARγ reduces the expression of perilipin and thus shuts down lipogenesis and increases lipolysis in existing adipocytes. Accordingly, respective supplements could in fact become "a highly safe and a promising dietary supplement" that has in addition to its already well-known beneficial effects on the immune system the ability the potential to "be used to promote human health globally" (Ono. 2012). But let's be honest, haven't we heard claims like that before?

Perceived recovery 48h after a workout correlates with free testosterone levels

(Sikorski. 2013) -- Yeah, I know the whole free testosterone after a workout discussion is pathetic, but what about free testosterone levels 48h hours after the workout, i.e. amidst the hot recovery phase? According to a soon to be published study in the Journal of Strength and Conditioning Research a standardized test to elicit the perceived recovery (PRS) appears to be surprisingly accurate to predict the drop in free testosterone after a session of high volume resistance training designed to elicit a large amount of fatigue and muscle damage. 
"All subjects participated in a high volume resistance training session consisting of 3 sets of 10-12 repetition maximum loads for each of the following exercises: full squats, bench press, deadlifts, pullups, bent over rows, dips, shoulder press, barbell curls and triceps extensions. Rest periods were 1 minute between sets, and 2 minutes between exercises." (Sikorski. 2013)
The scientists from the University of Tampa recruited 35 highly resistance-trained subjects (aged 21.3 ± 1.9 years) with an average squat, bench press, and deadlift of 1.7± 0.2, 1.38 ± 1.9 and 2.07 ± 2.7 times their bodyweight for their study. The subjects had a minimum experience of 3 years of resistance training and were thus probably way more capable to access their own recovery status than the average Jane or Joe after with a dozen of irregular workouts under her / his belt. Blood analyses, soreness and PRS tests were conducted at before, immediately after and 48h after the workout (total weight lifted in the training session was 16,353 ± 3,691.8 kg) and revealed ...
    Read more about the hormonal effects of different workout styles in this previous SuppVersity post
  • a significant increases in leg, chest and arm soreness from pre to post exercise,
  • a significant increases in creatine kinase (CK; measure of muscle damage) from 189.4 ± 100.2 to 512 ± 222.7 U/L (p < 0.05),
  • no changes in cortisol, testosterone, and free testosterone from pre to immediately post workout,
  • a significant moderate, and inverse relationship between leg soreness and PRS scores and  low, inverse relationships between chest and arm soreness and PRS scores, 
  • a significant, moderate inverse relationship between CK and PRS 
yet only when the CK values peaked 48h after the workout, however, the aforementioned "low, direct relationship with PRS" (Sikorski. 2013) was observed. As the researchers point out this result could be
"[...] important for those individuals that have neither the resources (time, monetary or otherwise) nor the expertise to draw blood and perform chemical assays to determine recovery status and or muscle damage. [...] This, in the bigger picture, may help appropriately design periodization plans designed aimed at functional overreaching and ensure proper overload. Moreover, and perhaps more importantly, the ability to indicate level of recovery following heavy resistance training expeditiously and accurately may be a critically important step in prevention of overtraining." (Sikorski. 2013)
The scientists do yet also emphasize that "future work is needed addressing other variable influencing recovery and long-term studies investigating the usefulness of the PRS in training" before a more general recommendation can be issued.



That's it for today folks. As usual there are a couple of interesting facebook posts for you to check out and discuss
  • Upping your vitamin D levels does nothing to reduce knee pain or cartilage loss in patients with symptomatic knee ostearthritis (read more)
  • "The one-two punch", retinoic acid suppresses obesity by both promoting energy expenditure and by inhibiting adipogenesis (read more)
  • More evidence of intrauterine dietary priming: Low protein in the womb + high caloric diet afterwards => insulin resistance (read more)
and obviously, you are invited to post your thoughts or questions on any of today's items in the comment area of this post.Aside from that, I wish all of you an exciting weekend ;-)

References:
  • Berg RD. Bacterial translocation from the gastrointestinal tract. Adv Exp Med Biol 1999, 473:11–30. 
  • Cani PD, Neyrinck AM, Fava F, Knauf C, Burcelin RG, Tuohy KM, Gibson GR, Delzenne NM. Selective increases of bifidobacteria in gut microflora improve high-fat-diet-induced diabetes in mice through a mechanism associated with endotoxaemia. Diabetologia. 2007 Nov;50(11):2374-83.
  • Ghanim H, Sia CL, Upadhyay M, Korzeniewski K, Viswanathan P, Abuaysheh S, Mohanty P, Dandona P. Orange juice neutralizes the proinflammatory effect of a high-fat, high-carbohydrate meal and prevents endotoxin increase and Toll-like receptor expression. Am J Clin Nutr. 2010 Apr;91(4):940-9.
  • Ghanim H, Sia CL, Korzeniewski K, Lohano T, Abuaysheh S, Marumganti A, Chaudhuri A, Dandona P. A resveratrol and polyphenol preparation suppresses oxidative and inflammatory stress response to a high-fat, high-carbohydrate meal. J Clin Endocrinol Metab. 2011 May;96(5):1409-14.
  • Ghanim et al. The Intake of Fiber Suppresses the High-Fat High-Carbohydrate Meal-Induced Endotoxemia, Oxidative Stress and Inflammation. Endocr Rev, Vol. 33 (03_MeetingAbstracts): OR03-1
  • Kawai Y, Kaneda K, Morisawa Y, Akagawa K. Protection of mice from lethal endotoxemia by use of an ornithine-containing lipid or a serine-containing lipid. Infect Immun. 1991 Aug;59(8):2560-6. Erratum in: Infect Immun 1992 Jan;60(1):320.
  • Laugerette F, Furet JP, Debard C, Daira P, Loizon E, Geloen A, Soulage CO, Simonet C, Lefils-Lacourtablaise J, Bernoud-Hubac N. Oil composition of high-fat diet affects metabolic inflammation differently in connection with endotoxin receptors in mice. Am J Physiol Endocrinol Metab. 2012;302:E374–386.
  • Mani V, Hollis JH, Gabler NK. Dietary oil composition differentially modulates intestinal endotoxin transport and postprandial endotoxemia. Nutrition & Metabolism. 2013;10(6).
  • Ono T, Morishita S, Murakoshi M. Novel  function of bovine lactoferin in lipid metabolism: Visceral fat reduction by enteric-coated lactoferrin. Pharma Nutrition. 2012 [accepted manuscript] 
  • Sikorski EM, Wilson JM, Lowery RP, Joy JM, Laurant CM, M-C Wilson S, Hesson D,
    Naimo MA, Averbuch B, Gilchrist P. Changes in Perceived Recovery Status Scale
    Following High Volume, Muscle Damaging Resistance Exercise. J Strength Cond Res.
    2013 Jan 2. [Epub ahead of print]
  • Tallis J, James RS, Cox VM, Duncan MJ. The effect of a physiological concentration of caffeine on the endurance of maximally and submaximally stimulated mouse soleus muscle. J Physiol Sci. 2013 Jan 6.
  • Vahouny GV, Tombes R, Cassidy MM, Kritchevsky D, Gallo LL. Dietary fibers: V. Binding of bile salts, phospholipids and cholesterol from mixed micelles by bile acid sequestrants and dietary fibers. Lipids. 1980 Dec;15(12):1012-8.

15 comments:

  1. I'm just wondering, you don't think that projecting data from pigs which consume a primarily vegetarian diet to humans, which consume a variety of different traditional diets(most of which are high in Sat. fat), is a rather poor way of interpreting whether saturated fats are harmful or not?

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    1. since pigs are opportunistic omnivores just like humans, they are at least a better model than mice, in whom it were the "bad" omega-6s who were harmful... in fact our digestive tracts are pretty similar and if they were not way more expensive than rats, I suspect scientist would use swine way more often

      "The swine species is closely comparable with man in many nutritional and digestive aspects, and thus provides ample opportunity to be used in investigations on the consequences of nutritional programming for the GIT" http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=7828572

      this is on gastrointestinal programming, but you will find similar statements on other aspects of the intestinal function.

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  2. "Moreover, what it the endotoxins were released in response to the antimicrobial effects of coconut oil."

    That's what I was wondering. Aren't most SFAs, as well as olive oil, which did worse than the other non-SFAs, anti-microbial? Would we see an increase in LPS after antibiotics or a large dose of garlic? It makes me wonder what a long-term study would show (reshaping of the gut flora?).

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    1. No, CO is in its own domain when antibiotic effects are in question. Olive oil is far from that league or any other SFA. Lauric acid is responsible, you have it in CO in huge amounts.

      The other reason might be abudance of short chain SFAs, which are more easily digested then other longer fats, hence introduce LPS quicker.

      One has to wonder if the effects would be the same after longer trial, once body adapts to coconut oil and flora recalibrates.

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    2. the thing about the long trial is about as good, as the question, whether the effects would have been different, if the baseline diet and thus the gut microbia composition had been different

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  3. Endotoxin is a signal for the innate immune system. Endotoxin deficient mice are prone to infection and death by the same cause, injecting them with a small dose of endotoxin rescues them.

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  4. The CO effect is probably due to its antimicrobial effect. This is easy to check, by using some other saturated fat (any research on that ?). Makes you wonder about pharma antibiotics ...

    This is highly contextual ofc - not only flora balance but also genetics determine the effects and vitamin levels (LPS knockouts for example suffer no ill effects, hence people with lower level of those receptors will be protected to certain extent).

    Its easily preventable by vitamin C dose, 1g should be enough before meal. There are really >20 papers showing this, here are some quickies, for humans and animals:

    http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0773.1998.tb01391.x/abstract

    Endotoxin significantly increased oxidative damage to liver proteins in animals receiving low doses of both vitamins, a result described here for the first time. This increase was totally prevented in guinea pigs supplemented with vitamin C alone or in combination with vitamin E, a treatment which strongly increased liver ascorbate.

    http://www.sciencedirect.com/science/article/pii/S0891584903003095
    In conclusion, strenuous short-term aerobic exercise [in humans] results in significant increases in plasma LPS levels (endotoxemia) together with increases in markers of oxidative stress. Supplementation with ascorbic acid, however, abolished the increase in LPS and nitrite but led to a significant increase in the ascorbate radical in plasma.

    Increased ascorbate radical is not of any concern IMO as it is taken by the brain, converted to AA or simply degraded. With lots of sugar around it might be minimally diabetogenic, but this is clearly not a problem for high fat/low carb diet. This is probably one of the reasons orange juice is good in this manner.

    This is why I always say to people - when going to high fat diet, use gram amounts of Vitamin C to reduce endotoxemia. Other supplements help too, particularly E but C is the cheapest and the longest researched one, if you need to pick 1, its C for sure.

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  5. While it's an interesting (if unsurprising) study, it's not like we can take anything really meaningful to human health out of it. Maybe if we did a similar set of trials in humans, but expanded it to include experimental groups for different fatty acid sources (say, lard, coconut, palm, and butter in the SFA branch, groups for different seed oils and fish and shellfish and insects for the PUFA and MUFA branches), groups testing those fats in individuals already accustomed to them vs. unaccustomed to them, and perhaps individuals from different geographic areas and cultures, who may have different gut biota. Perhaps then we could start sorting out some meaningful things about the relationship between lipid intake and human gut health. Let's not overstate the implications of a single simplistic study, particularly given majkinetor's valid point about the uniquely antimicrobial nature of CO potentially skewing the entire methodology.

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    1. totally agree, just had my daily serving of coconut oil with lunch today ;-) I mean - let's be honest all this is still in its infancy and the practical evidence speaks against negative effects on health and physique from coconut oil. I am not so sure about tons of lard, though... I mean look at the fatty acid profile of your everage lard, SFA + N6 = western diet stables

      Delete
    2. Indeed, I was simply suggesting it as among the milieu of fats that might have a distinct endotoxin effect not predicted by the 3 tested here. Heck, you could even test different lard sources if you wanted to get really in-depth; industrialized lard, bad as you mentioned, the lard I rendered last week from a local pig that mostly rooted in the woods and ate a bit of organic feed, and lard from coconut-fed pacific island pigs (supposedly almost entirely MUFA).

      Personally, I stick with the tallow from the grass-fed cows I helped raise for the most part. Very clean, stable, very low PUFA.

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  6. Well, that whole medium chain SFA --> endotoxemia thing was interesting enough to look into. So let's see... as we know, Gram(-) bacteria are so named because they do not accept the staining, the reason being that they have that outer membrane that the Gram(+) do not - said outer membrane blocks the stain. If we accept what seems to be the prevailing idea that the outer membrane also blocks the penetration of the lauric acid into the cell wall (and/or the inner membrane) where it lyses the bacteria, then lauric acid should work better on Gram(+) than Gram(-) bacteria. That seems to generally be the case as found in experiments.

    Yet the outer membrane of the Gram(-) that makes it hard to kill via SFA (or even some pharmaceutical antibiotics) is the very structure which incorporates the LPS. That's somewhat antithetical to the idea of endotoxemia resulting from CO bacteriocidal action: it's hard for lauric acid to kill the very bacteria that have the LPS in them.



    http://aac.asm.org/content/56/3/1157.full

    "lauric acid—against four Gram-negative bacteria and seven Gram-positive bacteria... Lauric acid (MBC range, 6.8 to 375.0 μg/ml) was active against all bacteria except E. coli, S. marcescens, and P. aeruginosa..." which is a failure in three of the four Gram(-)s but success in all 7 Gram(+)s.

    Also, notice that the rarely-mentioned sphingolipids do best of all.

    Notice that in Table 2 lauric acid does great (and fast) against 2 Gram(+)s, but not any Gram(-)s. Also the fatty acid called Sapienic acid (found only in humans hence the 'sapien' in the name) generally does better than lauric, it's in the sebum and apparently designed to fight bacteria on the skin - so not much chance of getting appreciable amounts in food.

    Some people naturally want to use CO to kill bad flora in the gut, but that presents some problems. When the SFAs are in TAG form, they apparently don't have the bacteriocidal action; they only work so as free FAs. Also, the MCTs tend to get directly absorbed higher up in the small intestine as TAGs, so they can't kill anything lower down the line anyway.

    Note also that the usually used measures (as for pharmaceutical antibiotics) are Minimum Bacteriocidal Concentration (MBC) and Minimum Inhibitory Concentration (MIB), these are *concentrations* so taking CO with food lessens it's killing power in the gut - it depends if you want to manipulate it that way or not because it might also kill the good guys. Concentrations arising in serum would be another matter.

    It seems, to me anyway after a lookthrough, that the concept of increased absorption as discussed by Mani et al is more plausible than the bacteriocidal angle. They say that increased gut permeability is likely not to blame, but that transcellular transport likely is, which makes me wonder why the body would do such a thing anyway --- except for the contained idea that the LPS just coincidentally gets carried along in chylomicrons with all the big fat load.

    I'd suppose that some LPS is present in the gut always from Gram(-)s dying all the time anyway, as a normal thing in life. That brings up the specter of occasional increased gut permeability (from excess exercise or food allergy or whatever) allowing ever-present LPS bits to get inside, whereas they'd normally get flushed. Just thinking out loud.

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    1. Your comment is awesome and I totally agree. It looks that stabilisation of lipid rafts introduces more LPS in the system as ... collateral damage... because I also expect such stabilisation to provide more of the micronutrients.

      Since microbita die all the time and immune system recalibrates depending on such events, this study is practically meaningless as it didn't allow for this adaptation to occur. Similar longer studies actually show the opposite result.

      One thing is odd - if high fat diets, meaning more lauric acid too, shifts flora toward gram negative bacteria (as its stated here, fact check required) that might very well mean there is some bactericidal action of lauric acid in the gut. It is supposed to be one of the reasons it is part of the human milk, to help with infections.

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    2. "the reason being that they have that outer membrane that the Gram(+) do not - said outer membrane blocks the stain."

      I could've sworn gram (-) outer membranes didn't block gram stain, it is the fact that their cell wall is much thinner and more porous that allows the initial stain to wash out.

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    3. it would actutally be interesting to monitor the consequences for say a week. or so. If we are really dealing with a "desintegration" of the cell walls in the bacteria (which I believe is very likely) you should see a decrease in basal and total LPS to either normal or (probably) even below normal levels after some time

      that said, this could also explain why people (me included) usually get diarrhea, when they introduce VCO in their diet - takes about 1-2 weeks and the problem is resolved

      Delete