Talk:Phytosterol

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Another cholesterol information source, consistent with 8-15% cholesterol drop from phytosterol when taken with cholesterol-containing food[edit]

http://jn.nutrition.org/cgi/reprint/133/6/1815

"Decreases in TC (total cholesterol) and LDL-C concentrations in this study are in agreement with data from other studies that examined the effects of phytosterols on blood lipid concentrations (15–17). In a controlled feeding experiment in which subjects consumed 1.8 g tall oil phytosterols/d, phytosterols caused a decrease in TC and LDL-C concentrations of 19.5 and 24.4%, respectively, compared to 10.4 and 8.9%, respectively, for the control diet not containing phytosterols (16). In other controlled feeding studies, overall decreases in TC were 4.9–6.8% (15) and 7.4% (17). These results are similar to those obtained in the present study, in which TC and LDL-C concentrations were decreased by 12.6 and 13.9%, respectively, in subjects who consumed the phytosterol-containing diet FctO. Therefore, it can be assumed that the dose of phytosterols given in this trial, �3.4 g/d, was appropriate and effective in optimizing changes in TC and LDL-C concentrations and was most likely the major factor responsible for the observed changes in TC and LDL-C concentrations."

aspirin coating[edit]

Now that Bayer has started to sell low-dose aspirin coated with phytosterols and making health claims, there should be something in the article about this. And, are all forms sold for human consumption plant-derived, or are some chemically synthesized? First, Bayer got a cease-and-desist from the FDA in 2008 for combining a drug (aspirin) with a dietary supplement (phytosterols/stanols). Second, they are plant-derived, either from soy or from tall oil, or other sources. -69.87.203.38 (talk) 20:53, 8 July 2008 (UTC)[reply]

WP: Food & Drink Assessment Commentary[edit]

This is a good article overall, and I assessed it as C-class due to a number of minor problems related to references.

  • There is at least one section without a reference.
  • There is at least one reference that's a bare url. Quotes need references.
  • And last, instead of a reference, a quote in the "Health Canada" section is followed by: This statement when used, shall be shown in letters up to the same size and prominence as those of the primary statement. I don't want to speculate what it means, but it should be removed, and the text should be scanned for any similar errors.

Good luck. Boneyard90 (talk) 11:44, 15 November 2011 (UTC)[reply]

Misleading health claims[edit]

Copied 2 paragraphs from User talk:Richiez

The interaction with Statins deserves a place in the lead. If Weingaertner specifically says the health claims were misleading, that contention should be spelled out in the body text, not just mentioned in passing in the lead. The term misleading implies (at least to my ear) a deliberate deception rather than an over-optimistic hypothesis. As with any controversial issue, countervailing opinions in credible sources should also be noted. Dankarl (talk) 13:45, 20 March 2012 (UTC)
I am not quite sure what to do about the article but would suggest to move the discussion to the article talk page where I will explain in more length. -- Richiez (talk) 14:17, 20 March 2012 (UTC)

Phytosterols do reduce cholesterol, well known and undisputed. However no CVD (or other direct outcome) benefit has been demonstrated, the latest meta-analysis confirmed that. Safety of phytosterol enriched foods has also been questioned. Unlike statins where cholesterol reduction is proven to reduce CVD and mortality the same for some unknown reason does not appear to hold for phytosterone enriched foods.

The article lists many health claims (approved by FDA etc), which can easily suggest some kind of beneficial effect where there is no evidence of any (and judging by todays evidence likely no effect at all). Apart from those officially sanctioned health claims some products used health claims that were regarded outright misleading (see for example Weingaertner/Phytosterols as adjunct to over-the-counter drugs).

Appart of that, I would expect that a normal diet with natural phytosterols is quite healthy but doubt that there is any evidence. Richiez (talk) 14:44, 20 March 2012 (UTC)[reply]

My point is about tone and the structure of the article. Dankarl (talk) 01:16, 21 March 2012 (UTC)[reply]
I hope fresh publications will clarify the uncertainty following the Genser meta-analysis soon so I would rather wait a while before tweaking it too much now. Richiez (talk) 18:50, 21 March 2012 (UTC)[reply]
I do think there should be some mention of modern work demonstrating cholesterol lowering. After your recent edits it sounds like the line of investigation was dropped in the 1980s or before. Dankarl (talk) 22:57, 21 March 2012 (UTC)[reply]
I typically leave the "pioneering work" and did not see the later work required to reinforce the point. Feel free to add it back, but it should not suggest benefit in clinical endpoints where there is no reason to assume there is any. Richiez (talk) 21:14, 22 March 2012 (UTC)[reply]
I'm not sure if you read the Genser et al. meta-analysis but it doesn't look at phytosterol supplementation at all, in fact it was looking at if there is an association between elevated phytosterol levels (not due to supplementation but due to diet or genetics, etc) and cardiovascular disease, so claiming that this meta-analysis made any assertion about the effectiveness of phytosterol supplementation in the prevention of cardiovascular disease would be incorrect. I have to also agree with Dankarl about the tone of the recent edits. JohnCAPSIC (talk) 01:20, 5 April 2012 (UTC)[reply]
Do you have any data documenting effect of phytosterol supplementation on CVD or mortality? Richiez (talk) 21:32, 5 April 2012 (UTC)[reply]
At present there are no hard endpoint trials for phytosterols, just like there are none for dietary fibre or the pharmaceutical ezetimibe, just like there are no hard endpoint trials that show saturated or trans fats increase heart disease. However there is a large pool of high quality clinical trials which show phytosterols lower cholesterol, cholesterol is a risk factor for CVD. Just because there are no trials that show phytosterols lower CVD does not mean that the FDA, EFSA and Health Canada do not have health claims for phytosterols saying they lower cholesterol. Your removal of those section from this article is inappropriate and biased, as are many of the other edits you have made. Might you have any expertise in CVD prevention and cholesterol lowering strategies or do you just have a fondness for big pharma? Und auf Englische heißt es "cholesterol" nicht "cholesterin"JohnCAPSIC (talk) 19:14, 9 April 2012 (UTC)[reply]
Please try to remain focused. There are no hard data - I was asking just in case I might have overlooked something. I have never denied the cholesterol lowering effect. Ezetimibe is a prime example why we should be extremely cautious in this situation and I have fixed that article a bit more now. Cholesterol lowering is no proof of anything.
The matter is much easier with ezetimibe where we have hard (negative) data which we can cite easily. We do not have anything for phytosterols but we still need to keep the article neutral and make sure phytosterol enriched foods are not portrayed "more favorable" than ezetimibe just because the manufacturers are unable or unwilling to produce hard data after 60 years of research and sales. Why are there so many "high quality clinical trials" and no results? This is not about some backyard herbalists but companies like Unilever and similar. The latest Danone sponsored meta-analysis gives me some hope that someone is at least willing to spend money on that and I think we should await the results.
Btw the data on statins is by no means so simple and clear as it used to be, I am certainly fine if you want to rephrase the positive statement about statins in this article.. it should come with a few conditions. Richiez (talk) 10:05, 10 April 2012 (UTC)[reply]
I couldn't agree more with you that hard-end point trials should be conducted with phytosterols. I did think that in your aim to remain neutral you may have gone to far by removing approved cholesterol lowering health claims section, and by putting the Weingartner et al. reference in the lead section of the article. Much of Dr. Weingartner's results discussed in the article you cite are from a genetically modified mouse experiment where the animals were fed 200 times the currently recommended human dose. I would like to add some of the health claim (cholesterol lowering, not CVD)sections (FDA,EFSA, Health Canada)back in, and the line "Co-administration of statins with phytosterol enriched foods increases adverse effects of phytosterols and may cause CVD" is not supported in the reference cited. I do agree that the statement that no CVD lowering has yet to be shown deserves to be in the top section. JohnCAPSIC (talk) 13:03, 10 April 2012 (UTC)[reply]
There should probably be a citation to Surrogate endpoints and some explanation of how that concept applies here.Dankarl (talk) 12:49, 10 April 2012 (UTC)[reply]
Completely agree, this whole debate is related to surrogate endpoints for CVD and hard endpoints. JohnCAPSIC (talk) 13:03, 10 April 2012 (UTC)[reply]
It would be good to mention, as well as the lipid hypothesis and how it failed in the ezetimibe case. Btw superficially it would appear that the mechanism of action of ezetimibe and phytosterol supplementation are rather similar in the way they reduce cholesterol levels? In practical terms I hope it won't get a terribly long and unwieldy article with pages of "political" statements. Adding all the FDA/EFSA statements is difficult without creating the impression that wikipedia does endorse something. The statements do not add anything new beyond the undisputed statement that phytosterols can reduce cholesterol levels but we would need to balance them somehow and explain why they are meaningless as long as there is no data on hard end points. On the other hand if we can find a way to explain that properly it would be a good thing. As of the co-administration of statins and phytosterols I can double check my references again but I would rather get rid of the section completely, as long as not even the basic facts are known it is just plenty of useless information. Rather hard to find a balance and I am not sure why we should try so hard to inflate the article instead of waiting for evidence. Richiez (talk) 13:53, 10 April 2012 (UTC)[reply]

I did a Pub-Med search yesterday, terms: phytosterol cardiovascular review and found several pertinent references from 2011. I am not going to maake any modifications to the article until I have read more than abstracts but i will share here a couple quick conclusions. 1) Phytosterols are still under active investigation; 2) they are somewhat controversial for the reasons Richiez has listed; 3) they have appreciable effects even when used with statins.

I do not think inclusion of the former text referencing the FDA/EFSA statements and recent work is giving the impression WP is endorsing anything, It is writing an article presenting the range of scientific opinion and fact as it presently exists.

I have no particular interest in rewriting the article - I came here originally hoping there would be some links on the metabolism of phytosterols in crustaceans, information I eventually found elsewhere, so if you guys can reach some consensus wording, great. Otherwise I'll take a crack at it sometime.Dankarl (talk) 23:16, 10 April 2012 (UTC)[reply]

The article could sure use more basic information. The section "structure" lists all kinds of related compounds and the naive reader is left guessing which are relevant in this article. I was also thinking, perhaps it can be improved and more information incorporated if the article would be better structured. A very quick preliminary draft would be this:
-phytosterols in biology
--natural occurrence and dietary intake
--endogenous synthesis and metabolism
---plants,animals,humans
--effects inside body
---atherogenic effects
---effects on cancer, antioxidant effect... (if any, current references look fairly miserably!!!!)
--dietary intake and reduction of cholesterol levels
---natural and modified phytosterols????
---enriched foods
--Phytosterols as a marker for cholesterol absorption

-health claims
-- intro on surrogate markers and boilerplate disclaimer
-- actual claims (although I hope 2 would be enough, this seems to be WP convention anyway)
-- controversy section
The information that was previously in "cancer risk", "mechanism of action", "coadministration of statins", "Sterol vs Stanol" sections could be merged somewhere sensible into "phytosterols in biology".
However this article is not anywhere close to my main focus, currently I have many other on my list which I consider more important and are easier subjects for me so I am not going to do much here. Also some or all the related articles need lot of love, it is a joke to claim that beta-Sitosterol is used in breast cancer treatment in Europe. Richiez (talk) 21:46, 11 April 2012 (UTC)[reply]

Behavior of plant sterols in animals[edit]

After reading this and related articles, I am struck by the following facts: (1) Chemically, phytosterols are very similar to cholesterol. (2) Phytosterols play the same role in plants as cholesterol does in animals. (3) In the intestine, phytosterols are absorbed in the same way as cholesterol, and compete with cholesterol, so that eating large amounts of phytosterols reduces the amount of cholesterol that the body will absorb from food.

This leads me to speculate that phytosterols behave like cholesterol in the human body. If you eat very large amounts of phytosterols will it replace some of the cholesterol in cell membranes? Or will the cells see phytosterols as imperfect or damaged cholesterol and destroy it, or refuse to take it from the blood?

If you eat large amounts of phytosterols it seems to me that it will replace some of the cholesterol in LDL and HDL in the blood. In this way measurements of cholesterol in the serum will show reduced levels (assuming the assays will not confuse phytosterols and cholesterol). On the other hand, LDL-phytosterol could be just as dangerous as LDL-cholesterol in causing artery disease. This would explain experimental results as they stand now.

Note that this does not even qualify as WP:OR -- it is pure guess work. I was wondering if any research looked at it this way or addressed these points in their conclusions. -- Solo Owl 13:51, 2 September 2013 (UTC) — Preceding unsigned comment added by Eall Ân Ûle (talkcontribs)

Mechanisms of cholesterol lowering[edit]

Contributed on 4-16-15 by GGT (talk); removed per WP:NOTJOURNAL

The exact mechanism through which phytosterols lower blood cholesterol levels is not known, and several hypotheses have been put forward. These include proposals that they compete with cholestrol for micellar solubility and displace it from bile salt micelles, that they crystallize together with cholesterol to form mixed insoluble crystals, that they interfere with the hydrolysis by cholesterol esterases and lipases to produce cholesterol and that they induce the secretion of cholesterol from blood vessels into the intestinal lumen to result in an increased sterol content in feces.

--Zefr (talk) 00:24, 17 April 2015 (UTC)[reply]

Zefr, thank you for your work here, I believe that the problem has to do with technical language. I have attempted to improve it below, if it is deemed appropriate, I could insert it:

Although the exact mechanism by which phytosterols lower blood cholesterol levels is not known, several hypotheses have been developed, including
  • preventing cholesterol from dissolving, facilitating its metabolism or excretion
  • forming insoluble crystals which are inhibited from entering the circulation
  • inhibiting cholesterol-forming enzymes, namely cholesterol esterases and lipases
  • promoting secretion of cholesterol from the blood vessels into the intestine where it is eventually excreted (GGT note: check on this one, as it sounds dubious)

--GGT (talk) 13:02, 19 April 2015 (UTC)[reply]

GGT -- perhaps bullets, with other copyedits and the respective references back in place? --Zefr (talk) 14:17, 19 April 2015 (UTC)[reply]

Deleted content[edit]

In this edit (→‎Cancer risk: rv as WP:PRIMARY, not WP:MEDRS), content supported by a review was deleted. The source meets WP:MEDRS and its current impact factor is 2.14. Added back.

Interestingly, a later edit let content supported by a primary source... Replaced with a systematic review. --BallenaBlanca (talk) 20:42, 19 September 2016 (UTC)[reply]

Fixed again [1] --BallenaBlanca (talk) 13:22, 22 September 2016 (UTC)[reply]

Not NPOV?[edit]

References 2 & 19 (Weingartner 22008 and Genser 2012) are cited as references that phytosterol treatment lowers cholesterol and LDL-chol, but has no impact on coronary heart disease. What these refs actually address is two sides of the debate as to whether phytosterols are atherogenic. What is presented is evidence that higher plasma phytosterols increase risk, or not. As to why there is not any reporting on the clinical consequences of phytosterol treatment, my guess is that the clinical trials are too short and too small to be a true test of cardio outcome. Instead, the trials were almost all designed to confirm lipid lowering and stop with that. David notMD (talk) 02:53, 3 May 2017 (UTC)[reply]