<p>I'd say it is a low-impact theory. The original (2004) paper in which this was proposed has around 60 citations in Google Scholar. That's pretty low for a paper like this (if the theory were influential). For contrast a <a href="https://www.ncbi.nlm.nih.gov/pubmed/10775018" rel="nofollow noreferrer">2000 paper on the monoamine hypothesis for depression</a> (which is far from being the first paper proposing it) has around 460 citations and <a href="https://www.ncbi.nlm.nih.gov/pubmed/10775017" rel="nofollow noreferrer">another one</a> on the same topic from the same year [probably a theme issue in that journal] has 440, again according to Google Scholar.</p>

<p>There have been some reappraisals of endocannabinoid deficiency theory, e.g. <a href="https://europepmc.org/abstract/med/24977967" rel="nofollow noreferrer">in 2014 by different authors</a> but in the same <a href="https://en.wikipedia.org/wiki/Neuroendocrinology_Letters" rel="nofollow noreferrer">low-impact publication</a> (IF &lt; 1) as the original proposal.</p>

<p>The initial propomotor of this theory has published <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5576607/" rel="nofollow noreferrer">his own reappraisal in 2016</a>, but I can't even find the impact factor of this latter venue.</p>

<p>In general, deficiency in a given neurotransmitter has failed to satisfactorily explain any single widespread psychiatric disorder. For depression and the monoamines (serotonin etc.) at least here are experimental protocols to test the hypotheses (e.g. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3756112/" rel="nofollow noreferrer">ATD</a>), but the results <a href="https://skeptics.stackexchange.com/questions/40309/is-depression-caused-by-chemical-imbalances">are fairly mixed</a>. Briefly looking at the 2016 paper on endocannabinoid deficiency theory,  I'm not even seeing an experimental way to test it like that. So it looks like the evidence is more circumstantial.</p>

CC BY-SA 4.0
2018-08-28T20:10:57.733Z
Thanks this is interesting. It’s mostly about depression though, and Russo doesn’t mention depression. He says endocannabinoids are deficient in people with migraines, fibromyalgia, and “related conditions”. That’s not to say depression couldn’t be an endocannabinoid deficiency, but I just don’t see anything in the papers that mention it. I’m wondering if there is anything explicitly false or misleading in Russo’s research.
Cannabijoy
CC BY-SA 4.0
2018-08-26T14:41:17.133Z
2018-08-26T14:41:17.133Z
got trolled too much this week
<p>There <a href="https://www.ncbi.nlm.nih.gov/pubmed/15159679" rel="nofollow noreferrer">was a study published</a> in <em>Neuro Endocrinology Letters</em> by Dr. Ethan Russo in 2004 that says many diseases being treated with cannabis correlate with an “endocannabinoid deficiency”, but I cannot read the study or find any more information about this. </p>

<p>Are there other studies that can confirm or deny this? Or are there strong or weak arguments in Russo’s study that can help us understand whether it’s a valid theory?</p>

CC BY-SA 4.0
2018-08-26T08:21:08.510Z
+1 for a good question and I have found that the study can be read in PDF format from http://www.academia.edu/download/32652999/Endocarbinoid_Defeciency.pdf
Chris Rogers
CC BY-SA 4.0
2018-08-29T00:28:09.710Z
@ChrisRogers thanks, but when I click on the link it just says “page not found”. I’m not sure how to subscribe to these academic websites.
Cannabijoy
CC BY-SA 4.0
2018-08-29T07:43:16.437Z
This is weird. It worked when I posted it. It doesn't work for me either now.  You don't need to subscribe.  It should just download. When clicking the link to it from the top [Google Scholar](https://scholar.google.co.uk/scholar?hl=en&as_sdt=0%2C5&q=endocannabinoid+deficiency&oq=endocannabinoid+de) search result (the academia.edu pdf link), it works and it doesn't go anywhere different
Chris Rogers
<neurophysiology><neuro-transmitters><medication>
Is Dr. Russo’s “endocannabinoid deficiency” a valid theory?
Cannabijoy
# Is Dr. Russo’s “endocannabinoid deficiency” a valid theory?

(Asked by: username_0 on 2018-08-25)

There [was a study published](https://www.ncbi.nlm.nih.gov/pubmed/15159679) in *Neuro Endocrinology Letters* by Dr. Ethan Russo in 2004 that says many diseases being treated with cannabis correlate with an “endocannabinoid deficiency”, but I cannot read the study or find any more information about this.

Are there other studies that can confirm or deny this? Or are there strong or weak arguments in Russo’s study that can help us understand whether it’s a valid theory?

**Tags:** neurophysiology, neuro-transmitters, medication

> **Comments:**
> **username_1**: +1 for a good question and I have found that the study can be read in PDF format from http://www.academia.edu/download/32652999/Endocarbinoid_Defeciency.pdf  
> **username_0**: @ChrisRogers thanks, but when I click on the link it just says “page not found”. I’m not sure how to subscribe to these academic websites.  
> **username_1**: This is weird. It worked when I posted it. It doesn't work for me either now.  You don't need to subscribe.  It should just download. When clicking the link to it from the top [Google Scholar](https://scholar.google.co.uk/scholar?hl=en&as_sdt=0%2C5&q=endocannabinoid+deficiency&oq=endocannabinoid+de) search result (the academia.edu pdf link), it works and it doesn't go anywhere different  

---

## 1 answers

### Answer by username_2 on 2018-08-26. Score: 2

I'd say it is a low-impact theory. The original (2004) paper in which this was proposed has around 60 citations in Google Scholar. That's pretty low for a paper like this (if the theory were influential). For contrast a [2000 paper on the monoamine hypothesis for depression](https://www.ncbi.nlm.nih.gov/pubmed/10775018) (which is far from being the first paper proposing it) has around 460 citations and [another one](https://www.ncbi.nlm.nih.gov/pubmed/10775017) on the same topic from the same year [probably a theme issue in that journal] has 440, again according to Google Scholar.

There have been some reappraisals of endocannabinoid deficiency theory, e.g. [in 2014 by different authors](https://europepmc.org/abstract/med/24977967) but in the same [low-impact publication](https://en.wikipedia.org/wiki/Neuroendocrinology_Letters) (IF < 1) as the original proposal.

The initial propomotor of this theory has published [his own reappraisal in 2016](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5576607/), but I can't even find the impact factor of this latter venue.

In general, deficiency in a given neurotransmitter has failed to satisfactorily explain any single widespread psychiatric disorder. For depression and the monoamines (serotonin etc.) at least here are experimental protocols to test the hypotheses (e.g. [ATD](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3756112/)), but the results [are fairly mixed](https://skeptics.stackexchange.com/questions/40309/is-depression-caused-by-chemical-imbalances). Briefly looking at the 2016 paper on endocannabinoid deficiency theory, I'm not even seeing an experimental way to test it like that. So it looks like the evidence is more circumstantial.

> **Comments:**
> **username_0**: Thanks this is interesting. It’s mostly about depression though, and Russo doesn’t mention depression. He says endocannabinoids are deficient in people with migraines, fibromyalgia, and “related conditions”. That’s not to say depression couldn’t be an endocannabinoid deficiency, but I just don’t see anything in the papers that mention it. I’m wondering if there is anything explicitly false or misleading in Russo’s research.  

---

