Here's a highly useful and relevant podcast by Mark Manson, especially for those of us who identify as "self help junkies".
Basically, they did a thorough analysis of 19 of the most common self help techniques. Some very interesting conclusions. Without giving the game away (it's an entertaining listen), 7 of the top 10 practices come from antiquity. Most of the junk concepts arose (unsurprisingly) in the past 50 years