Waiting for this to show up on sci-hub so I can provide a more useful analysis, but observational findings are super common in nutrition and while they are often extremely circumspect for the reasons outlined by @Dr_Cog@mander.xyz, sometimes studies do have a good amount of adjustment factors. Given the hazard ratio and a confidence interval which is close to including 1, I don’t think these findings are particularly strong (which is fairly usual in nutrition based studies).
However, in the context of what we already know about nutrition, we know that hitting a certain amount of dietary fat is associated with reducing the risk of depression. Other nutritional factors are likely important, and studies like this can help when we do meta-analysis to deduce what factors play a role even when our science isn’t as controlled as we’d like it to be
Some meta-studies on dietary factors of depression: 12
Good point on observational studies being of limited use.
People who eat nuts may be less likely to eat chips or processed food in general.
So an observational study probably wouldn’t tell whether the nuts themselves have positive effects or not.
But it’s probably not a bad thing unless you’re allergic.
I think it’s fair to think of it in the context of, if you already struggle with depression and you enjoy eating nuts, this is just an excuse or a little nudge/reminder that it probably won’t hurt to do so and might have a minor positive effect. I think that’s useful information and we shouldn’t focus too heavily on whether we fully understand the science.
Waiting for this to show up on sci-hub so I can provide a more useful analysis, but observational findings are super common in nutrition and while they are often extremely circumspect for the reasons outlined by @Dr_Cog@mander.xyz, sometimes studies do have a good amount of adjustment factors. Given the hazard ratio and a confidence interval which is close to including 1, I don’t think these findings are particularly strong (which is fairly usual in nutrition based studies).
However, in the context of what we already know about nutrition, we know that hitting a certain amount of dietary fat is associated with reducing the risk of depression. Other nutritional factors are likely important, and studies like this can help when we do meta-analysis to deduce what factors play a role even when our science isn’t as controlled as we’d like it to be
Some meta-studies on dietary factors of depression: 1 2
Good point on observational studies being of limited use.
People who eat nuts may be less likely to eat chips or processed food in general. So an observational study probably wouldn’t tell whether the nuts themselves have positive effects or not. But it’s probably not a bad thing unless you’re allergic.
I think it’s fair to think of it in the context of, if you already struggle with depression and you enjoy eating nuts, this is just an excuse or a little nudge/reminder that it probably won’t hurt to do so and might have a minor positive effect. I think that’s useful information and we shouldn’t focus too heavily on whether we fully understand the science.