One thing worth noting is this appears to be entirely correlation, not causation.
It's possible that it is not diet, but an additional factor. For example, perhaps people who are worried about their impact on the world are more likely to be depressed and also more likely to be vegetarian/vegan.
If that were the case, it's plausible that the same person, even if they ate meat, would have an identical chance of being depressed.
Another thing to note is that they did not control for anything except sex. My, not totally scientific, observation is that depression and anxiety is more prevalent in people under a certain age, as is concern about the environment, as is veganism. I'd be curious if controlling for age made any difference. Maybe it's just millennials are just a both more-depressed and more-vegetarian cohort.
Levels of meat consumption are also linked to location, and I think depression might be too. I'd be curious if controlling for location made any difference. Maybe people living in big cities are both more likely to be vegetarian (due to restaurants catering to more dietary preferences due to mass of people) and more likely to be depressed.
I personally like the original theory I proposed. Someone who is self-conscious about their existence is more likely to be worried about the environment (especially their personal impact), is more likely to be vegetarian, and also is more likely to be depressed.
I think we need either a proposed nutritional link / mechanism, or a controlled study in which people's diets were changed, to draw the conclusion the title implies.
It's possible that it is not diet, but an additional factor. For example, perhaps people who are worried about their impact on the world are more likely to be depressed and also more likely to be vegetarian/vegan.
If that were the case, it's plausible that the same person, even if they ate meat, would have an identical chance of being depressed.
Another thing to note is that they did not control for anything except sex. My, not totally scientific, observation is that depression and anxiety is more prevalent in people under a certain age, as is concern about the environment, as is veganism. I'd be curious if controlling for age made any difference. Maybe it's just millennials are just a both more-depressed and more-vegetarian cohort.
Levels of meat consumption are also linked to location, and I think depression might be too. I'd be curious if controlling for location made any difference. Maybe people living in big cities are both more likely to be vegetarian (due to restaurants catering to more dietary preferences due to mass of people) and more likely to be depressed.
I personally like the original theory I proposed. Someone who is self-conscious about their existence is more likely to be worried about the environment (especially their personal impact), is more likely to be vegetarian, and also is more likely to be depressed.
I think we need either a proposed nutritional link / mechanism, or a controlled study in which people's diets were changed, to draw the conclusion the title implies.