Talk:Proanthocyanidin

Barely Literate in Spots

This piece was written by someone who is barely literate in science. Numerous instances of poor diction and grammar, uncritical and vague thinking, and as others have commented, it reads like an advertisement. The only thing lacking is links to a supplement webs site. For example, the author writes "Proanthocyanidins cross the blood-brain barrier. This enables proanthocyanidins to fight free radicals in the vessels of the brain that in turn will help them remain healthy." What??!*? If something crosses the BBB this means that it escapes the vessels proper and gets into the tissue(s)!! It's really an embarrassment, given that this class of polyphenols is thought to have some solid health benefits and important bioprotective effects in relationship to all the diseases of aging. Clearly, these extend well beyond the popular categorization of this group of compounds as "antioxidants." Someone experienced in this area should overhaul this entire piece. It's a mess. 207.180.129.233 (talk) 23:30, 2 October 2008 (UTC)DFW, Harvard Medical School[reply]

Most of this article sounds more like a bad advertisement then a description.

"proanthocyanidins have been reported in double-blind research to reduce the duration of edema after face-lift surgery from 15.855468 to 11.486745222 days." I really don't think that any kind of study could attain the accuracy that the number of significant figures suggests; the last "2" in that number would be 173 microseconds!

"The Sun's ultraviolet rays destroy up to 50 percent of our skin cells. Proanthocyanidins reduce this amount to approximately 15 percent." WHAT!...is this in a hour...a day...a year...because I'm not sure i want to go outside anymore. Skin cells turn over rapidly, but losing 50% of ones "skin cells" at once sounds pretty serious!

Ashton.

I’ve changed those numbers on trial data from 9 to 3 significant figures. It is ridiculous to suggest that this research is that precise. Even 3 are unjustified, but as it’s still unreferenced it’s a moot point. It would be nice if somebody can find the source. Dbaynard (talk) 16:34, 11 June 2010 (UTC)

The opening paragraph in this section is actually quite arrogant. In fact proanthocyanidins probably do reduce free radicals thereby benefiting the brains blood vessels. The poster seems to think that letting everyone know that their having attended Harvard Medical School somehow bestows some kind of authority on the subject of nutrition. How ironic. Medical schools, including Harvard, have been notorious for lagging far behind the scientific research on nutrition and health, most of which has been driven by biochemists, not Medical Doctors.

75.166.172.10 (talk) 07:43, 22 August 2010 (UTC)[reply]

An advert for supplements

"An important supplement, the proanthocyanidins found in pine bark and grape seed extract work directly to help strengthen all the blood vessels and improve the delivery of oxygen to the cells. Doctor recommended as anti-oxidants, they have become increasingly more important as our environment deteriorates through the introduction of toxins from pollution.......(more).....Unlike most other nutritional supplements, the beneficial effects of proanthocyanidins cross the blood-brain barrier........". Seems like advertising to me. 80.0.108.3 (talk) 10:25, 8 March 2008 (UTC)[reply]

The advertising section begins at "...proanthocyanidins have been reported in double-blind research to reduce the duration of edema after face-lift surgery..." and ends at "...can result in increased mental acuity, a decreased potential for stroke, and possibly in fighting senility." This is such a blatant lift from a nutrient/supplement advertising brochure that it cannot remain in the article as it is. It has no references and I see no supporting articles in my reading. The absurd face lift quote is evidently a hack. So I propose to delete this section entirely. I'll wait a week for comment. The section "Oligomeric proanthocyanidins" is more in line with current papers, but needs more references. I think it should stay, but should be footnoted better. Curious Violet (talk) 00:37, 5 June 2008 (UTC)[reply]

A young genius

Hehe, if he found Vitamin P in 1936, he was a genius at 14 years old... He was born in 1922. —Preceding unsigned comment added by 85.134.201.20 (talk) 23:19, 31 March 2008 (UTC)[reply]

Authors of supporting references being paid by wine or nutrient companies

Roger Corder, author of 3 of the references used in this article: "Roger Corder has received funding for research and to attend symposia from Catena Wines, Argentina, and Canandaigua Wine Company, New York, US. He is also author of The Wine Diet, scheduled for publication in January 2007 by Little, Brown Book Group." (see http://www.nature.com/nature/journal/v444/n7119/box/444566a_audecl.html) Regardless of whether research in this article is scientifically sound or not, I think this article has rather a smell of snake oil. There is money involved if claims made here are true. See my comment under "An Advert..." above. Curious Violet (talk) 00:37, 5 June 2008 (UTC)[reply]

A vary large quantity of the literature is like this and it does not affect the data and the peer reviewers will nuke most papers that are overly biased. (Money is not all that available.) That said the Wikipedia article does need work. Jasoninkid (talk) 17:44, 5 March 2009 (UTC)[reply]

About eight times more of it in apples than in wine

See especially Figure 5 in this academic article http://jn.nutrition.org/cgi/content/full/130/8/2086S Apples have about eight times the amount of it per serving compared with wine. Could someone add this reference to the article for me please - dont know how. Alcohol has its dangers, apples have other benefits. From figure 5 it seems that wine has the least amount of it of all the foods shown. 80.0.98.236 (talk) 16:47, 21 June 2008 (UTC)[reply]

Primary Research

There is a lot of data here that is not well established in the scientific comity (one unreproduced paper is not definitive)and needs to be denoted or removed. Jasoninkid (talk) 19:47, 5 March 2009 (UTC)[reply]

Also Uses Reads like it was cut and pasted from a journal article. Jasoninkid (talk) 19:53, 5 March 2009 (UTC)[reply]

Many foods have more proanthocyanidin in them than wine

"Many other foods and beverages also contain high amounts of OPCs, but very few come close to the levels found in red grape seeds and skins (which readily disperse into grape juice when crushed).[37]". If you read through reference 37 then you see that the second clause of that sentance is not true - lots of foods have more Proa... in them than wine, some extremely much more. Reference 7 also says there is more Proa... in apples than wine. 92.15.0.66 (talk) 15:30, 8 March 2011 (UTC)[reply]

Article Rewrite

I'm going to take some consideration as to the rewrite of this article, one section at a time. I'm going to simplify the article into what I believe are core topics of useful information, which can be expanded on.

With regards to the introduction, I propose that the image of the chromatogram be removed, as all this really does is show what a chromatogram looks like. Such an image would be more suited to an article dedicated to describing methods for polyphenol/flavonoid analysis.

I will take note of the content of the article as it stands now, but any text without citations I'm just going to remove until I find similar information from a reputable source.Markwdck (talk) 19:07, 14 November 2011 (UTC)[reply]

Porter Assay

The section below appears to be out-dated information with only primary references. I'm removing it from the Article subsection, Analysis, to here for review, comment or editing. --Zefr (talk) 17:51, 25 April 2014 (UTC)[reply]

An improved colorimetric test, called the Porter Assay or butanol-HCl-iron method, is the most common PCO assay currently in use.The Truth About PCOs, Debasis Bagchi, Ph.D. on www.activin.com^{[self-published source?]} The unit of measurement of the Porter Assay is the PVU (Porter Value Unit). The Porter Assay is a chemical test to help determine the potency of procyanidin containing compounds, such as grape seed extract. It is an acid hydrolysis, which splits larger chain units (dimers and trimers) into single unit monomers and oxidizes them. This leads to a colour change, which can be measured using a spectrophotometer. The greater the absorbance at a certain wavelength of light, the greater the potency. Ranges for grape seed extract are from 25 PVU for low grade material to over 300 for premium grape seed extracts.Porter Assay on www.omegabiotech.com^{[unreliable medical source?]}

2017 status of UTI studies

This edit by Britrochtay does not represent the state of expert review as of 2017. Particularly, the statement, "research is conflicting and more studies are needed", misleads because the most thorough research is not conflicting, represented by the EFSA review and the Cochrane review, which together establish the current most thorough scientific consensus. Certainly, more studies are needed and will be done, but the highest quality evidence is that PACs are not proven to have an effect on UTI. Accordingly for the encyclopedia, there is no reason to be vague about "conflicting research", and we should state the best evidence as it currently exists. --Zefr (talk) 02:36, 12 December 2017 (UTC)[reply]

Neutral Point of View

The lede to this article states:
"'proanthocyanidins were once proposed as factors inhibiting urinary tract infections in women, but this research has been refuted by expert scientific committees"
However, the expert opinion cited do NOT refute this.
The Scientific Opinion, dealing solely with a particular product, ONLY opines that "a cause and effect relationship has not been established between the consumption of CranMax® and reduction of the risk of urinary tract infection". It does NOT refute proanthocyanidins in toto "as factors inhibiting urinary tract infections".
The Cochrane review cited, and applauded in the latest comment here as "the most thorough research", in fact states the opposite:
"Cranberries contain a substance (proanthocyanidins) that can prevent bacteria from sticking on the walls of the bladder. This may help prevent bladder and other UTIs."
It summarizes the studies reviewed by saying:
"There was a small trend towards fewer UTIs in people taking cranberry product compared to placebo or no treatment but this was not a significant finding. Many people in the studies stopped drinking the juice", pointing to general weaknesses in the research/research design and to it being related to particular products (ie not to proanthocyanidins in general).
Most significantly though, in my opinion, the report concludes:
"Cranberry products (such as tablets or capsules) were also ineffective, possibly due to lack of potency of the 'active ingredient' (although had the same effect as taking antibiotics). "
The view expressed in the lede to the article and elsewhere is therefore contrary to the statements being cited to justify it, these statements coming from "the most thorough research.
LookingGlass (talk) 18:57, 5 August 2021 (UTC)[reply]

I revised the lede to state that there is no conclusive evidence that PACs are effective for treating UTIs. The two contrary sources shown under Research are less-rigorous as sources for UTI treatment (compared to the EFSA and Jepson sources), but are present for the reader to see this is a controversial, inconclusive subject. Zefr (talk) 19:27, 5 August 2021 (UTC)[reply]