Please don't rewrite article titles like this.
"Overall, our findings reveal that vegetarians report poorer health, follow medical treatment more frequently, have worse preventive health care practices, and have a lower quality of life."
Which is unfortunately too long for HN submission, but is the (in fact, verbatim) published summary. A revised headline might read, Without any substantial editorialization or modification of meaning:
"Vegetarians report poorer health...and...lower quality of life."
Aruably the word "report" is more neutral than "have", but is substantially similar to the submission. All that being said if you guys want to change it...it is absolutely your perogotive. Its just hard to avoid making certain compromises (imperfect title or imperfect article). This is unfortunately one of those corner cases IMHO.
It goes without saying that the published academic title ishopelessly vague for anyone not already familiar with the results. To wit:
"The Association between Eating Behavior and Various Health Parameters: A Matched Sample Study"
Has infinite degrees of freedom.
[1] An third party edited and published title highlight what it is 'newsworthy' (ie, this is not self edited). The original research was submitted (ie, mismatched) to increase the quality and availability of the information provided to readers.
Actually that's not what the research concludes. You left out "Austrian adults who eat a vegetarian diet". That's different than American vegetarians, who are a much larger group with a different and longer culture of being aware of issues like B12, etc.
On the substance of your point, however, I appreciate the comments. A discussion of the limitations of the study cohort and methodology is certainly a good discussion topic.
I would caution the notion "americans" are superiour at being vegetarian. Other cultures are more natively vegetarian. EG, The Indian Sub-continent and Bhuddists in Nepal, etc. And have genetic and cultural adaptations much longer in gestation as a result.
Also, context switching doesn't solve the key issue: non-vegetarians veg-native cultures also self-selct. Ethnic variation is also a vexing problem in this area because of phenotypic variation (race, lactose tolerance etc) linked with health.
A study of vegetarian-dominant cultures may show something entirely different. Yet also not be applicable to the US population.