> These food groups, which are an important part of the Mediteranean diet, are associated with an increased abundance of bacteria with anti-inflammatory properties. That well-studied diet is known not only to affect the gut microbiome by increasing the abundance of microbes that produce short-chain fatty acids (SCFAs), but also to shorten episodes of depression.
I downvoted because by the HN guidelines comments should try to be curious and interesting and because “Please don't post shallow dismissals”.
The abstract mentions that diet affects gut microbiome and that gut microbiome has a “shaping effect” on psychiatric disorders:
> “A growing body of literature shows that the gut microbiome plays a shaping role in a variety of psychiatric disorders, including major depressive disorder (MDD). In this review, the interplay between the microbiome and MDD is discussed in three facets. First, we discuss factors that affect the onset/development of MDD that also greatly impinge on the composition of the gut microbiota—especially diet and stressful life events.”
That is, the comment is low effort, and dismissive, and unsubstantiated speculation. Are we supposed to conclude that “depressed people eat junk food” is all there is to it? Citation requested. Are they just saying “depressed people eat junk food”? Boring. Are they saying “maybe depressed people eat junk food”? Is there a reason to have “maybe” there? Might they not?
It's not shallow and it's not a dismissal. Just because it can be expressed in one simple sentence doesn't make it a bad idea. He never said that this is the only thing going on.
Causality, and the reason they think it could be diet->mood instead of the other way around, is discussed in the original link, so this comment adds nothing and in fact subtracts by being less informed than the link itself.
Imagine a HN link to a paper which summarizes various other studies for the causes of failures in auto navigation systems. Dozens of studies are cited, which covers areas such as incomplete testing due to schedule pressures, not adhering to coding guidelines for safety, lack of redundancy or self checking mechanisms, hardware failure, unanticipated overruns of scheduler time budgets due to a confluence of exceptions, etc.
Next, imagine someone leaves a comment which leaves the impression they didn't read the paper, only the title, and said, "Maybe they use too many GOTOs."
Finally, imagine someone saying, "Not sure why you are getting downvoted, this is a good point."
Is your comment adding an informed opinion on this topic? Or are you perhaps smart in one area and think you can just wing an opinion on this topic?
I live with someone with clinical depression. One of the most maddening things for her is the astounding number of people who have absolutely no idea what they are talking about offering "helpful" opinions. No, they aren't helpful, they are hurtful.
When someone trivializes the problem such as you have, it adds the body of disinformation on the topic that seeps into mainstream opinion: that depressives have done something to deserve what they are suffering, or that there is some simple solution that they just too stupid or unwilling to do that will fix things, or that they have some perverse desire to remain depressed, or they lack the character to "buck up" and put their depression behind them.
But, if some external force compelled the person in question to run several miles every day, lift heavy weights, sleep a lot, and eat perfect food, that person would probably be meaningfully less depressed within half a year. Obviously with feedback being what it is it's not that simple, but still. Speaking as someone with clinically diagnosed depression btw. It's a lot of unpleasant effort to kill depression but it's not impossible, and it's the only way to do it. Drugs and talk therapy can help a lot but fundamentally the change has to happen of one's own volition
Would you please stop posting unsubstantive comments to HN? You've done it a lot, unfortunately, and we're trying for something different here.
If you've read the paper and found a reason to criticize the work for not taking this obvious objection into account, your comment should say specifically what that reason is. If not, then "Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something." https://news.ycombinator.com/newsguidelines.html
Threads are sensitive to initial conditions, so it's particularly important not to post crap comments when a thread is new. Since it takes time for more thoughtful comments to start appearing, conscious restraint is needed here.
I agree, and since sibling comments request more specific criticism here goes.
Let's look at section "Gut Microbiome Can Transfer Depression". They cite two animal studies. Two. Animal. One of them find their sucrose preference changes. This is dietary preference change. That bacteria changes dietary preferences is well established and we don't need to invoke depression to explain it. What about the other? "The forced swim test led to conflicting outcomes; the study in mice found an increased immobility time, associated with depressive-like behavior, whereas the rat study found no difference." Flimsy, flimsy, flimsy.
Until stronger evidence merge, I agree the most likely explanation is that depressed people eat junk food to comfort themselves, or because they are too depressed to give a shit what they do to their bodies.
Exactly. It's difficult to make causal claims from observational data, and made worse by the constant flood of causal claims coming out of microbiome labs. At best there's anecdotal evidence, at worst researchers are peddling snake-oil.
And to clarify, I have worked on microbiome research. The whole field is a mess.
It seems that microbiome research is always defended here. Perhaps it is scientific, but be aware that a multi billion dollar industry depends on "improving" the microbiome.
I wouldn't necessarily equivocate all of that research. Very little of it, even in the realm of dietary impact, has to do with probiotics, and the research that does focus on probiotics largely doesn't suggest a lasting impact on the microbiome.
Notwithstanding that there may be health benefits to probiotic consumption.
That is how we here think, but for covert advertising it is sufficient to get the word "microbiome" in the news as often as possible and to stress that it's important.
The average consumer does not read probiotics research, all that sticks is "Microbiome causes X, probiotics should fix it!".
The average consumer is still a whole newscycle behind on that, but I think it's a stretch to say research in itself is advertisement. Headlines (which often do not even reflect the actual research content) might be advertisements.
There is a lot of evidence it is related, however that's not the same thing of course as being able to modulate symptoms via the microbiome (that one poop transplant study was extremely preliminary). I think the jury is still out on that latter idea, but current probiotics surely have no effect. I hope that as this line of research continues industry will adapt and we will start to see probiotics that are A) better at actually populating the gut and B) personalized.
Indeed, the paper in question here was sponsored by grants to the APC Microbiome Institute. Not that that means the work isn't solid, but it's certainly something to bear in mind while reading.
Any thought on imalanced microbiome being a second order effect rather than a cause? I’d guess continued stress responses from the nervous system could cause chronic gut problems
Every time a scientific article "x may cause y" is posted, there are a couple dozen "correlation does not equal causation" retorts, as if the researchers involved were unaware of this exceedingly basic and elementary principle.
It's such a waste of comment - an intellectual platitude. Can you point specifically to how this research is flawed, or how alternative research offers a better explanation?
33 comments
[ 4.5 ms ] story [ 71.8 ms ] thread> These food groups, which are an important part of the Mediteranean diet, are associated with an increased abundance of bacteria with anti-inflammatory properties. That well-studied diet is known not only to affect the gut microbiome by increasing the abundance of microbes that produce short-chain fatty acids (SCFAs), but also to shorten episodes of depression.
The abstract mentions that diet affects gut microbiome and that gut microbiome has a “shaping effect” on psychiatric disorders:
> “A growing body of literature shows that the gut microbiome plays a shaping role in a variety of psychiatric disorders, including major depressive disorder (MDD). In this review, the interplay between the microbiome and MDD is discussed in three facets. First, we discuss factors that affect the onset/development of MDD that also greatly impinge on the composition of the gut microbiota—especially diet and stressful life events.”
That is, the comment is low effort, and dismissive, and unsubstantiated speculation. Are we supposed to conclude that “depressed people eat junk food” is all there is to it? Citation requested. Are they just saying “depressed people eat junk food”? Boring. Are they saying “maybe depressed people eat junk food”? Is there a reason to have “maybe” there? Might they not?
That's just the closest rule cited as there isn't one that merely explicitly states "don't post unsubstantial fluff". Maybe there should be.
Next, imagine someone leaves a comment which leaves the impression they didn't read the paper, only the title, and said, "Maybe they use too many GOTOs."
Finally, imagine someone saying, "Not sure why you are getting downvoted, this is a good point."
I live with someone with clinical depression. One of the most maddening things for her is the astounding number of people who have absolutely no idea what they are talking about offering "helpful" opinions. No, they aren't helpful, they are hurtful.
When someone trivializes the problem such as you have, it adds the body of disinformation on the topic that seeps into mainstream opinion: that depressives have done something to deserve what they are suffering, or that there is some simple solution that they just too stupid or unwilling to do that will fix things, or that they have some perverse desire to remain depressed, or they lack the character to "buck up" and put their depression behind them.
If you've read the paper and found a reason to criticize the work for not taking this obvious objection into account, your comment should say specifically what that reason is. If not, then "Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something." https://news.ycombinator.com/newsguidelines.html
Threads are sensitive to initial conditions, so it's particularly important not to post crap comments when a thread is new. Since it takes time for more thoughtful comments to start appearing, conscious restraint is needed here.
Let's look at section "Gut Microbiome Can Transfer Depression". They cite two animal studies. Two. Animal. One of them find their sucrose preference changes. This is dietary preference change. That bacteria changes dietary preferences is well established and we don't need to invoke depression to explain it. What about the other? "The forced swim test led to conflicting outcomes; the study in mice found an increased immobility time, associated with depressive-like behavior, whereas the rat study found no difference." Flimsy, flimsy, flimsy.
Until stronger evidence merge, I agree the most likely explanation is that depressed people eat junk food to comfort themselves, or because they are too depressed to give a shit what they do to their bodies.
And to clarify, I have worked on microbiome research. The whole field is a mess.
Here's an ad in nature.com:
https://www.nature.com/articles/d42473-019-00336-9
Notwithstanding that there may be health benefits to probiotic consumption.
The average consumer does not read probiotics research, all that sticks is "Microbiome causes X, probiotics should fix it!".
It's such a waste of comment - an intellectual platitude. Can you point specifically to how this research is flawed, or how alternative research offers a better explanation?
I bring up Celiac because 1/ I have it, and 2/ there is very little medical doubt / uncertainty / controversy about the disease.