Talk:Resveratrol

Concerning lack of scientific neutrality

I am hugely concerned with the lack of neutrality in this article. It consistently purports that there is no evidence for any positive health effects which just isn't the view reflected in current literature. This page needs updating to include a more neutral comparison of studies, rather than to push a single perspective.

One of many such examples is Petrovski et al, who states: "Resveratrol, initially used for cancer therapy, has shown beneficial effects against most degenerative and cardiovascular diseases from atherosclerosis, hypertension, ischemia/reperfusion, and heart failure to diabetes, obesity, and aging."

This includes specific biological mechanisms which can't just be ignored in an page supposedly representing an unbiased, informative summary.

I see there has been heavy redaction of edits which again is concerning. I won't waste my time with edits that will be immediately deleted but I whoever is responsible needs to drop their agenda and allow the page to correctly reflect that there is widely conflicting evidence regarding human health implications. 2A00:23C8:2D8D:B01:A981:EF85:580E:8F8D (talk) 15:46, 6 May 2022 (UTC)

If by "Petrovski et al" you mean PMID:21261638 that's a rather old source. It's important that Wikipedia accurately reflects current accepted knowledge on this topic. So if there are any decent sources we're not using it would be good to hear about them. Alexbrn (talk) 16:13, 6 May 2022 (UTC)

To the IP editor: provide one WP:MEDRS review of randomized controlled trials published in the last 5 years showing any clinically-relevant health effect. Resveratrol has been only a topic of lab research - mainly in vitro - too preliminary and unconfirmed to be encyclopedic. Its fate in vivo is impossible to assess, as it is catabolized into fragments and rapidly excreted after digestion. The Petrovski study was from 2011, was out of the mainstream science at the time, and remains so, as there are no rigorous follow-up reviews in reputable clinical publications over the last decade. Zefr (talk) 16:25, 6 May 2022 (UTC)

You say this is a rather old source, yet the article consists of several sources that are older than the Petrovski study. It was simply an example, anyone that takes time to review the literature can see there are dozens of such studies, as well as ample secondary research that openly state the accepted health benefits as well as the biological mechanism of action in many cases. The review by Galiniak et al (2019) states: "Overall, resveratrol has potential benefits for human health and exhibits protective effects against glycation, free radicals’ production, neurodegeneration, inflammation, and tumor development." and importantly "Many in vitro and in vivo studies suggest that resveratrol has anti-cancer properties due to its wide range of activities, including antioxidant effects and regulating the expression of pro-apoptotic proteins, as well as molecules underlying tumor development.", "In summary, the results indicate that resveratrol may be considered as a beneficial anti-glycation agent in in vitro and in vivo experiments as well as in the treatment of diseases associated with increased glycation.".

Berman et al (2017) has a well balanced review stating: "In diabetic patients, resveratrol was able to increase insulin sensitivity, decrease blood glucose levels, and positively regulate several other biomarkers associated with diabetes."

Zhang et al (2021) goes as far as to state "it is possible that RV can be considered the best nutritional additive and a complementary drug, especially a therapeutic candidate." and "Consequently, it is possible to recommend RV as a promising agent for treating many human diseases." I tend to think this enthusiasm is premature but it shows a clear conflict of attitudes towards RV in the field.

Personally, I find the Ramírez-Garza (2018) review to be most informative as it is well balanced, and describes possible reasoning behind the variation in clinical trials. It also clearly identifies the many studies showing positive clinical effects.

At no point do I think RV is something to be recommended to the public, bioavailability, production, and dose-dependant paradoxial effects all need further research. However the only thing there appears no real support for is life-extensive properties, and so the wikipedia article claiming 'no evidence of beneficial effects' is misleading at best and factually false at worst. I don't know if this is just an oversight or whether there is an active agenda to keep the article so negatively biased but I hope that it can be edited to be more reflective of the current literature standing. 2A00:23C8:2D8D:B01:11B3:B607:D931:39 (talk) 11:35, 7 May 2022 (UTC)

I looked at your favourite source. It's published in a MDPI journal. So, dodgy and useless for our purposes. Alexbrn (talk) 11:55, 7 May 2022 (UTC)

Yes, this is definitely a problem. WP:DUE weight is not being given to mouse studies etc. RadioactiveBoulevardier (talk) 22:40, 8 March 2023 (UTC)

Effects on cancer and scientific proof

I recently read a book, written by Åhlberg, M., which states multiple scientific sources for resveratrol health effects, including preventing cancer. Here's one source it mentions: Md Alauddin, A. Sultana, Y. Kabir (2021). "Potential of Nutraceutical in Preventing the Risk of Cancer and Metabolic Syndrome: From the Perspective of Nutritional Genomic". It may be worth revisiting this topic, but since there's already discussion on which sources are considered reliable, I'll refrain from changing. Unelsson (talk) 21:54, 12 December 2022 (UTC)

The paper you mention [1] is currently not a reliable source for Wikipedia. The journal [2] it was published in is not indexed by BIOSIS, Scopus or PubMed. Psychologist Guy (talk) 22:13, 12 December 2022 (UTC)

Ah, I see, but still, a search on PubMed gives several articles on resveratrol cancer prevention and treatment. There are meta-reviews and research articles. Keyword "resveratrol cancer prevention" gives 488 matches for years 2012-2023. I checked a few, and many state that resveratrol has effects on cancer, e.g.: [3] (2015) "Polyphenolic compounds exert an antioxidant protective action against GC.", [4] (2019) "Resveratrol is a promising agent for colorectal cancer prevention and treatment", [5] (2021) "...has been shown to...affect the initiation and progression of many diseases, including cancer". Unelsson (talk) 22:50, 12 December 2022 (UTC)

If we are talking about health effects then we need high-quality clinical evidence, those reviews you are citing are not high-quality and the last was an MDPI publication, that is unreliable. The problem is that clinical trials are still lacking in this area. A good balanced review which was cited above by an IP is this review paper [6] which states "From these clinical trials, it is clear that there is still much to learn about the use of resveratrol as a cancer therapeutic. It seems that resveratrol may have specificity for certain types of cancers, but even this is difficult to definitively conclude given the small number of clinical trials that have been conducted". The conclusion is that there is some promising research but not enough to be making any specific statements about health effects on cancer. In 10 years we will probably have more research and a better understanding.

The statement on the article there is no "high-quality evidence that resveratrol improves lifespan or has a substantial effect on any human disease" is accurate, it is not saying there is no evidence, just not high-quality evidence from clinical trials. It may change in the future but more clinical data is needed. Psychologist Guy (talk) 23:41, 12 December 2022 (UTC)

How about the statement "As of 2020, there is no evidence of an effect of resveratrol on cancer in humans"? I understand the research so that there is evidence of an effect, even if no high-quality clinical trials. It seems a bit strong wording, should it also say "no high-quality evidence"? Unelsson (talk) 23:55, 12 December 2022 (UTC)

I see what you are saying, but this might just boil down to a semantics dispute. If you do a search for the exact words "no high-quality evidence" in the Wikipedia search bar in regard to health effects, this is actually found on many articles including Omega-3 fatty acid (in regards to supplements), Dark chocolate, Isothiocyanate, Cumin, Health effects of tea, Grape therapy, Fenugreek, Verbena, Quercetin, Sea buckthorn oil etc. I don't have a problem with the wording personally because it is accurate. You probably know all this already but if you read Hierarchy of evidence and WP:MEDASSESS it is all explained there. If health effects are going to be stated on Wikipedia then high-quality evidence from systematic reviews of randomized controlled trials must be cited and not just a one off review, the evidence must be consistent and preferably backed by statements from medical organizations. It's clear that on many of these nutritional topics there is evidence but it is not high-quality. Psychologist Guy (talk) 00:20, 13 December 2022 (UTC)

HSV-Alzheimer's & Resveratrol.

1) You may want to keep an eye on research done at Tufts University to gage the effect of chemical compounds on Herpes Simplex Virus-caused Alzheimer's. Resveratrol had a positive effect. I understand that this is a primary research, but it may appear in reviews if it holds up. Keep a weather eye.

'Screening neuroprotective compounds in herpes-induced Alzheimer's disease cell and 3D tissue models',
Free Radical Biology and Medicine, Volume 186, June 2022, Pages 76-92, Isabella A. Silveira, et al.
https://www.sciencedirect.com/science/article/pii/S0891584922001770

From the conclusion: "We describe the application of a rapid and robust herpesvirus-induced AD model to screen a panel of medications, supplements, and nutraceuticals for their neuroprotective properties. Our screen identified two promising candidates, green tea catechins and resveratrol, with strong anti-plaque and functional neuroprotective benefits, coupled with minimal neurotoxicity."

2) I know that predatory journals have become a huge problem. (I think that ScienceDirect / Elseveir are supposedly reliable.) Where can I find information of journals considered to be predatory - under the Reliable Sources discussions on Wikipedia?

Thank you for your time, Wordreader (talk) 23:29, 15 November 2023 (UTC)

WP:CITEWATCH - see disclaimer. Zefr (talk) 23:44, 15 November 2023 (UTC)

Alzheimer's section and meta-analysis

This edit relied on a 2022 meta-analysis which I accessed via the Wikipedia Library. The report does not convey a lot of confidence, with limitations including the usual deficiencies in supplement research, as quoted from the article (my letters added):

a) The small number of studies included (n=4) should be considered, as well as

b) the heterogeneity related to the design of the interventions (resveratrol alone and in combination with glucose and malate),

c) study duration (12 weeks vs 52 weeks), resveratrol dosage (isolated resveratrol: 2000 mg/ day vs RGM: 5 g/day), and

d) reduced number of evaluated volunteers, which makes it difficult to carry out a quantitative analysis.

For the primary studies, considering the assessment of

e) the risk of bias between the studies, and

f) the insufficient clarity related to the randomization process in two of the studies [32, 33] should also be considered.

Such limitations are a significant weakness, and may warrant removal of this new section as too preliminary. Zefr (talk) 01:59, 5 September 2024 (UTC)

Agree with your concerns and would support complete removal of this. Only 4 RCTs were included in the qualitative analyses and the paper admits there are only limited human studies. This is very weak and should be deleted in my opinion. Psychologist Guy (talk) 02:41, 5 September 2024 (UTC)

I think it can stay given the properly cautious way it is couched here. But I wouldn't strongly object to removal either. WP:ECREE may be a consideration. Bon courage (talk) 02:51, 5 September 2024 (UTC)

The only other review I have seen in this topic area is this umbrella review [7] it would be interesting to know your take on it, they only looked at six systematic reviews which is low for an umbrella review, but that is the limitation of this topic area. 4 of these were human. There seems to be an agreement that resveratrol and its metabolites have the potential to traverse the blood–brain barrier but there are a lot of limitations of this kind of research including the variability in dosages. Looks like there are a lot of issues with this type of research and little to no consistent results. Psychologist Guy (talk) 03:09, 5 September 2024 (UTC)

It's a non-MEDLINE journal so I'd be hesitant to use it; claims of therapeutic benefit really need strong sourcing. Bon courage (talk) 03:15, 5 September 2024 (UTC)

The umbrella review gives a 'Limitations' section of about 10 deficiencies common among supplement clinical studies. If resveratrol or any unproven phytochemical proposed to treat human diseases was a synthetic drug candidate, it would have been terminated when two such deficiencies were revealed.

It would be refreshing if authors or journal editors of a systematic review or meta-analysis as discussed here would just say, "we had mostly crappy studies to evaluate, but decided to go ahead with publication anyway." Zefr (talk) 05:32, 5 September 2024 (UTC)

It might be worth keeping a heads up on the journal it was published in. Originally when I clicked on the review I thought it was published in a British Medical Journal, however it was actually published by Springer [8]. Judging from the poor quality of the review they might be publishing other unreliable reviews. I did a quick scan of Nutrition & Metabolism on Wikipedia. It appears the journal is cited on around 30 articles. Psychologist Guy (talk) 18:54, 5 September 2024 (UTC)

As I understand Wikipedia, it's not the role of Wikipedia editors to exercise their own judgement about the quality of studies in deciding what to include or exclude, but simply to report the studies (as long as from a reliable source). Instant Editor. — Preceding unsigned comment added by Instant Editor (talk • contribs) 20:11, 5 September 2024 (UTC)

You understand wrong; assessing source quality is a cornerstone of editing. Bon courage (talk) 20:40, 5 September 2024 (UTC)

Can you show me a policy regarding that? Basing exclusion or inclusion on whether WE think it's a quality study seems something like "original research."— Preceding unsigned comment added by Instant Editor (talk • contribs)

Maybe start with WP:BESTSOURCES and WP:MEDASSESS. If you want to get a clue about how the community has assessed numerous sources over the years maybe consult WP:RSP and WP:CITEWATCH. Bon courage (talk) 21:01, 5 September 2024 (UTC)

MEDASSESS says "The best evidence for efficacy of treatments and other health interventions comes mainly from meta-analyses of randomized controlled trials (RCTs)"

Yes. And that should be the end of story, rather than editors arguing amongst each other whether a meta-analysis of RCT's is high quality ENOUGH. A meta-analysis of RCTs is already quality by definition. As long as it's from a reliable source. There might be a bad meta-analysis of RCT's out there, but we should have to rely on reliable source that make that judgement claim, not claim that ourselves. I for one am not going to waste my time arguing whether a particular meta-analysis of RCTs is a high quality one or not. Wikipedia can go on without me if that's what it's going to come down to. Instant Editor (talk) 21:22, 5 September 2024 (UTC)

"A meta-analysis of RCTs is already quality by definition". No it isn't. That is not how evidence-based medicine works. The meta-analysis must be of good quality with significant results. The data should be consistent. There is no point in citing 1 weak meta-analysis from limited data published in weak journal. These-days you can find an meta-analysis published for almost anything in nutrition. Just because someone publishes a meta-analysis does not make it valid. You need to read over the methodology and results. There are too many limitations with the meta-analysis you cited and none of the results have been replicated. Psychologist Guy (talk) 01:02, 6 September 2024 (UTC)

Indeed. That said, the first of the sources mentioned here is not the most terrible and I think this[9] treatment of it is suitably cautious. Bon courage (talk) 05:09, 6 September 2024 (UTC)