Maybe depressed people eat a lot of junk food.
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.
> 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.
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.
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.
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."
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.