Is chiropractic worthwhile for health improvement without specific health issues?

Chiropractic may be beneficial for mild back pain, in much the same way a good back massage would. However, chiropractic has never been demonstrated to alter the course of any specific disease entity. If the chiro starts making specific health claims, such as being able to cure your asthma, hypertension and diabetes,etc, then you need to get up and run away from them.

Any Chiropractic "treatment" should be focused on a specific musculoskeletal issue. So, periodic "maintenance" adjustments in people who do not have specific musculoskeletal symptoms will do nothing to improve over-all health. If your back is healthy, it does not need routine manipulation to stay healthy.

There is no good evidence that they are anything more than glorified massage therapists.

To the chiro’s, show us evidence to the contrary.
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EDIT
@ sahajrob
Regarding the Bakris hypertension study. This pilot study is not convincing.

The study design was poor for starters, the authors claim it was a double blind study, it evidently wasn’t. In a DBS neither the people doing the study nor the subjects know who is receiving placebo or actual treatment but in this study the investigators knowingly applied either treatment or sham intervention. It’s less than clear from the methods if the same investigators then performed the blood pressure recording and if this was the case, there is obviously room for bias.

Also, BP fluctuates all the time. Short term spikes in hypertension are not thought to cause the same effects on the body as BP that is consistently high. When making a diagnosis of hypertension, this is best done with ambulatory readings (over a period of 24 hours) to get an accurate analysis of BP. If lower BP was observed based on just a few readings after the study, one cannot conclude that high blood pressure has actually been reduced significantly enough to have an over all effect on health and the need for anti-hypertensive medication eliminated. How long did this SMALL reduction in BP last for?

"14 mm Hg greater drop in systolic blood pressure and an average 8 mm Hg greater drop in diastolic blood pressure" was observed, this isn’t a huge drop. This can very easily be confused with normal fluctuations.

Finally the trial was quite small. Even the authors themselves said that no firm conclusions can be drawn on a study this small. So to mention this study is quite pointless and it really does not contradict what I has said. Also you said yourself, the questions wasn’t about a specific health issue… :)

"Anyhow your post is off topic as the question was 4 general health NOT specific health issues. Just a rant as I see it."

"Health improvement" is vague. If there is no specific health concern, then I am not sure what health needs improving? And as I stated in my answer, there is no evidence that routine manipulation of the back helps the back or health in general. I’m unsure what the questioner is referring to…. diet and lifestyle? Prevention of illnesses? My answer wasn’t just about specific health claims, however I did point out that any chiro who advises he can help with any of those conditions mentioned is best avoided.

And there is no good evidence that chiro helps asthma.