Talk:Hydroxytyrosol

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Additional references[edit]

Here are some references that were pasted into the article, but apparently were not used to write the article. However, they may be useful for adding new content. -- Ed (Edgar181) 18:49, 15 February 2008 (UTC)[reply]

Extended content

1.- The phenolic compounds of olive oil: structure, biological activity and beneficial effects on human health 2.- Olives and olive oil in cancer prevention. 3.- Olive oil hydroxytyrosol protects human erythrocytes against oxidative damages. 4.- Bioactive compounds in foods: their role in the prevention of cardiovascular disease and cancer. 5.- Antioxidant effect of hydroxytyrosol, a polyphenol from olive oil: scavenging of hydrogen peroxide but not superoxide anion produced by human neutrophils. 6.- Inhibition of cell cycle progression by hydroxytyrosol is associated with upregulation of cyclin-dependent protein kinase inhibitors p21(WAF1/Cip1) and p27(Kip1) and with induction of differentiation in HL60 cells. 7.- In vivo Effect of the Natural Antioxidant Hydroxytyrosol on Cyclosporine Nephrotoxicity in Rats. 8.- High-yielding synthesis of methyl orthoformate-protected hydroxytyrosol and its use in preparation of hydroxytyrosyl acetate. 9.- Hydroxytyrosol protects retinal pigment epithelial cells from acrolein-induced oxidative stress and mitochondrial dysfunction. 10.- New insights into controversies on the antioxidant potential of the olive oil antioxidant hydroxytyrosol. 11.- Effect of the olive oil phenol hydroxytyrosol on human hepatoma HepG2 cells. Protection against oxidative stress induced by tert-butylhydroperoxide. 12.- Inhibition of hemoglobin- and iron-promoted oxidation in fish microsomes by natural phenolics. 13.- The olive oil antioxidant hydroxytyrosol efficiently protects against the oxidative stress-induced impairment of the NObullet response of isolated rat aorta. 14.- Hydroxytyrosol lipophilic analogues: enzymatic synthesis, radical scavenging activity and DNA oxidative damage protection. 15.- Effects of olive oil and its minor constituents on serum lipids, oxidative stress, and energy metabolism in cardiac muscle. 16.- The fate of olive oil polyphenols in the gastrointestinal tract: implications of gastric and colonic microflora-dependent biotransformation. 17.- Comparison of the concentrations of phenolic compounds in olive oils and other plant oils: correlation with antimicrobial activity. 18.- Capillary electrophoresis-electrospray ionization-mass spectrometry method to determine the phenolic fraction of extra-virgin olive oil. 19.- Lipophilic hydroxytyrosyl esters. Antioxidant activity in lipid matrices and biological systems. 20.- Antioxidant effect of two virgin olive oils depends on the concentration and composition of minor polar compounds. 21.- Daily consumption of a high-phenol extra-virgin olive oil reduces oxidative DNA damage in postmenopausal women. 22.- Dihydroxyphenylethanol induces apoptosis by activating serine/threonine protein phosphatase PP2A and promotes the endoplasmic reticulum stress response in human colon carcinoma cells. 23.- Virgin olive oil phenols inhibit proliferation of human promyelocytic leukemia cells (HL60) by inducing apoptosis and differentiation. 25.- Postprandial LDL phenolic content and LDL oxidation are modulated by olive oil phenolic compounds in humans. 25.- Isolation and identification of radical scavengers in olive tree (Olea europaea) wood. 26.- Physicochemical properties of natural phenolics from grapes and olive oil byproducts and their antioxidant activity in frozen horse mackerel fillets. 27.- Metabolism of the olive oil phenols hydroxytyrosol, tyrosol, and hydroxytyrosyl acetate by human hepatoma HepG2 cells. 28.- One-month administration of hydroxytyrosol, a phenolic antioxidant present in olive oil, to hyperlipemic rabbits improves blood lipid profile, antioxidant status and reduces atherosclerosis development. 29.- Diverse effects of natural antioxidants on cyclosporin cytotoxicity in rat renal tubular cells. 30.- Antioxidant and anti-atherogenic activities of olive oil phenolics. 31.- Hydroxytyrosol, a natural antioxidant from olive oil, prevents protein damage induced by long-wave ultraviolet radiation in melanoma cells.

Comment on physical properties[edit]

The flash point listed in the chembox is based on a 5% solution in ethanol, i.e. it is the flash point of ethanol! This is apparent if one actually reads the MSDS link. Tekmeme (talk) 17:29, 17 July 2014 (UTC)[reply]

The boiling point is far too low for this molecule at normal pressure. The true pressure is 0,02 mm Hg according to: Shmuel Yannai: Dictionary of Food Compounds with CD-ROM, Second Edition. CRC Press, 2012, ISBN 978-1-420-08352-1, S. 519 ([1], p. 519, at Google Books).

Adverse events and safety[edit]

As an extract, hydroxytyrosol is a dietary supplement with no proven effects in humans. There are no data establishing adverse events and safety from long-term use in humans, no human health benefits of hydroxytyrosol are confirmed and no reason to state in the encyclopedia what rat data suggest might apply to humans, as user Hyperforin wishes to do with this edit. Including such WP:FRINGE information clutters the article with non-secondary, non-human sources per WP:NOTJOURNAL. The section can be more simply stated without using rat data. --Zefr (talk) 05:13, 7 May 2016 (UTC)[reply]

Rat data is the only means of establishing a NOAEL. Or did you actually think that a LD50 was defined using human trials? --Hyperforin (talk) 05:16, 7 May 2016 (UTC)[reply]
Irrelevant information for a fringe topic. --Zefr (talk) 05:21, 7 May 2016 (UTC)[reply]
You are also ignorant and dead wrong about hydroxytyrosol not having proven effects in humans,[2][3]. But what would you expect from someone who routinely blanks his Talk page to cover up conflicts. --Hyperforin (talk) 05:23, 7 May 2016 (UTC)[reply]

I agree 100% with the other unfortunate user who had his content removed by Zefr. I posted material from the National Cancer Institute from the US National Institute of Health. That was also rejected. The real agenda here is that the editors of Wikipedia consider their own opinion to be better than the best research institutes in the world. The claim from Zefr that there are only trials on rats is factually incorrect. I posted good review articles discussing the results of recent, human clinical trials. — Preceding unsigned comment added by Jbtuk (talkcontribs) 13:14, 3 July 2021 (UTC)[reply]

I also found had the experience of Zefr blanking his talk page after I posted a message to him. He is arrogant and opinionated and threatens to report people if they don't agree with him. I also added a short comment on the typical amounts of hydroxytyrosl used in commercial products. This was simply intended as a useful guide and clearly is empirical in nature. Even that was deleted.

I tried to reach out to other users on this page, and I see they have had their accounts frozen. I expect Zefr is trying to do the same to me. This type of action is completely against free speech.

Role in human health[edit]

Why did Zefr revert my addition of information from a secondary source? Norman21 (talk) 08:28, 9 July 2017 (UTC)[reply]

All of the research on HT is primary and there is no convincing evidence that HT is produced endogenously or has any significant biological effect in vivo. The article you cited is based mostly on early-stage research which the authors craft into wild speculation. It is preliminary research at best with little to no value for the encyclopedia. --Zefr (talk) 15:01, 9 July 2017 (UTC)[reply]
Actually, the article in question, i.e. https://www.ncbi.nlm.nih.gov/pubmed/25781069, is a proper review article. It is not up to Zefr to give it the low weight that he thinks is appropriate. MEDRS doesn't require that articles conform to Zefr's wild speculation of what's valid and what's not. --Acyclic (talk) 16:52, 9 July 2017 (UTC)[reply]
I can't get the article ATM but from the abstract there's no indication that Hydroxytyrosol has "a role in human health". What specific passages in the source support that assertion? Alexbrn (talk) 16:54, 9 July 2017 (UTC)[reply]
Says the person who ignored the link http://www.mdpi.com/1420-3049/20/3/4655/htm, sections 1 through 7. --Acyclic (talk) 17:02, 9 July 2017 (UTC)[reply]
Thanks (sorry I encountered this behind a paywall and assumed all copies would be so walled, so didn't click). But I see now this is an MDPI journal. Dodgy. I suggest ignore this source, especially for any exceptional (i.e. health) claims. Alexbrn (talk) 17:05, 9 July 2017 (UTC)[reply]
This is not a WP:MEDASSESS article with high-quality evidence; its science level is in the pink portion of the pyramids. This is a review of laboratory research with no relevance at this stage to human health or disease. At best, it could be in a section describing preliminary research. --Zefr (talk) 17:07, 9 July 2017 (UTC)[reply]
That's your unqualified personal opinion, Zefr, and you can't use it to tell others what to do. --Acyclic (talk) 17:09, 9 July 2017 (UTC)[reply]
Looking over the source and discussion above, I think it best not to use it. I am impressed with the caution that the researchers take and caveats they present in their "Concluding Remarks" section. --Ronz (talk) 17:48, 9 July 2017 (UTC)[reply]
MDPI is a borderline predatory publisher - this is not a source that we should use. Jytdog (talk) 18:54, 9 July 2017 (UTC)[reply]
Interesting - I didn't realize this was a rule used in Wikipedia (that wasn't meant to sound sarcastic - honest!). Is there a list of "quality" journals somewhere? Or is a high impact factor the criterion? Norman21 (talk) 21:50, 9 July 2017 (UTC)[reply]
:) Unlike other subject matter areas of WP, sources for health content (the biomedical literature) are well stratified, and we really rely on that.
We aim to provide high quality content to the public, and everything depends on sources, and the higher the quality the better. For journals, yes reviews from very high impact journals are very welcome. Most journals are of course middle. We generally avoid things from the low end (very low impact factor, not indexed in MEDLINE, anything predatory). The more iffy the content, the higher quality source is needed - extraordinary claims require extraordinarily high quality sourcing. With food/phytochemicals the world is littered with poor quality primary sources and hype from the dietary supplement industry, so we treat health claims in this area as rather extraordinary.
But in general, source quality for health claims is discussed at WP:MEDASSESS. Jytdog (talk) 22:34, 9 July 2017 (UTC)[reply]
Sounds a little arbitrary, but if those are the rules, I'll play by them. Thanks for the clarification. Norman21 (talk) 09:11, 10 July 2017 (UTC)[reply]

‎Clinical studies[edit]

@Jbtuk and Mimijoh: Repeating what I wrote on my talk page:

Per WP:MEDRS, when it comes to medical claims, it is essential that they be backed up by reliable secondary sources (i.e., review articles). The reason for this is clear. An alarmingly high percentage of biomedical research simply cannot be repeated and the results of clinical trials often contradict each other. Review articles weigh the available evidence and only come to a definitive conclusion if the evidence warrants it. Boghog (talk) 20:41, 20 April 2021 (UTC)[reply]

GRAS[edit]

Concerning this edit, the FDA does not take a position on food safety ingredients, such as hydroxytyrosol, nor does it "approve" an ingredient as safe. Manufacturers wanting to include an ingredient submit a safety dossier, which the FDA reviews. If there is no FDA objection, the ingredient is considered safe or GRAS, but it remains the manufacturer's responsibility to assure safety and include public information on safe levels of the ingredient. See this. There have been four manufacturer submissions about hydroxytyrosol safety in food products, shown here, with one application pending for olive pulp extraction. Zefr (talk) 21:39, 2 July 2021 (UTC)[reply]