Lessons From Studying Over 100 Self-Help Books and 20 Therapies

By Spencer Greenberg and Jeremy Stevenson.

Over the past five years, my colleague Jeremy Stevenson and I have read more than 100 self-help books, studied over 20 therapies, and extracted and categorized nearly 500 techniques from those sources.

The goal was to understand the high-level patterns across all methods of self-improvement, as part of our process of writing our book, The 12 Levers, aimed at providing a complete psychological toolkit for improving your life.

Today, we want to share five lessons that stood out from conducting all of this research.

Lesson 1: A lot of techniques are recycled or repackaged

Take mindfulness, defined by meditation teacher Jon Kabat-Zinn as “the awareness that arises by paying attention on purpose, in the present moment, and non-judgementally.” The Pali word “sati” (roughly translated as mindfulness) appears in early Buddhist teachings dating back about 2,500 years. Mindfulness is now used in multiple modern therapies, like acceptance and commitment therapy (ACT), dialectical behavior therapy (DBT), mindfulness-based cognitive therapy (MBCT), mindfulness-based stress reduction (MBSR), and mindful self-compassion (MSC).

Sometimes mindfulness is repackaged with a different name. For example, ACT therapists call mindfulness of thoughts “defusion” and mindfulness of body sensations “expansion.” Mindfulness also goes by “decentering,” "acceptance,” and “distancing.”

Is it bad that self-help techniques get recycled and repackaged? Well, it can contribute to that sense of overwhelm when we’re surveying the shelves of the bookstore’s self-help aisle. But it’s a good thing if it means making effective techniques more available. And it’s also good if it means making old techniques that may have been described in obscure language easier to understand.

Lesson 2: A lot of self-help techniques don’t have as much evidence as you’d think

Cold exposure is a great example. It has become incredibly popular. And from all the hype, you’d think that daily cold showers or plunges have multiple randomized controlled trials (RCTs) showing consistent benefits for all sorts of outcomes like anxiety, depression, and energy levels.

A 2025 meta-analysis did find some benefits from cold exposure, including lower physiological stress 12 hours later, better self-reported sleep, improved quality of life after 30 days, and 29% fewer sick days. But it found no stress benefits immediately — 1, 24, or 48 hours later; no quality-of-life benefits after 90 days; and no general mood improvements. At best, the evidence is mixed.

Here’s what the authors of the meta-analysis concluded: “the current evidence base is constrained by few RCTs, small sample sizes, and a lack of diversity in study populations.”

(Funnily enough, cold exposure is also an example of a “repackaged” technique. References to cold exposure date back as early as ancient Greece and possibly even ancient Egypt.)

Lesson 3. Some techniques work better than others, but only on average

Some psychological techniques really are better than others. Much better. For example, if you want to reduce your anxiety, exposure therapy is the most evidence-based approach, and it's effective for a lot of people (though not for everyone).

In terms of other questions, like who should reframe their thoughts versus be mindful of them, or who should use cognitive techniques versus behavioral techniques, or who should use CBT techniques versus DBT techniques, not much is actually known.

The reality is that, while the worst techniques are useless for everyone (beyond giving a potential placebo effect), even the best techniques don't work for everyone.

This lack of a one-size-fits-all solution in self-improvement can be frustrating. But thankfully, this also means you have a lot of freedom in choosing which techniques to try.

4. At a fundamental level, you control surprisingly little

Focusing on what you control is an essential principle of life. There’s a reason why the ancient Stoics emphasized it so much. As Epictetus put it, “Some things are in our control and others not.” If you try to change things outside of your control, you can waste a lot of energy and potentially cause yourself a lot of unnecessary suffering. This is also a major reason why our book focused on the most useful techniques of self-help, because techniques are controllable processes.

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One thing we discovered from reviewing scores of self-help books and therapies is that, at our core, there are only four things we each fundamentally control. Just four! You have control (albeit not total control) over: your body, your communication, your thoughts, and your attention. That's not very much!

To illustrate, imagine you’re unjustly locked in a jail cell that’s completely empty except for a chair. You’re surrounded by concrete walls, and you can’t see or hear what’s happening outside. You’re completely alone.

In this situation, what do you truly have control over? You certainly can’t control what’s happening outside of the jail cell. And you can’t change much inside the cell either (concrete tends to be fairly unmalleable).

But you can do certain things. You can speak, even if no one can hear you. And you can move your body, even if you can’t escape.

What if the guard came into the cell, strapped you to the chair, and taped your mouth shut? Well, you wouldn’t be able to move or speak anymore. But you’d still control some things. You could still control your thinking, at least to some extent (e.g., you could choose to fantasize about how you could escape).

And you could still control your attention (e.g., you could focus on the voice of the guard or the feeling of the straps on your wrists). Even if you were blindfolded, this attentional control would still be available. In fact, it would still be available even if you were temporarily paralyzed.

Remembering that we have control of just four things can help us remember to focus only on what's controllable, rather than wasting energy trying to change what we can't.

5. Hundreds of self-help techniques exist, but they all boil down to just 12 broad strategies for improving your life

After extracting nearly 500 techniques from 106 self-help books and 23 therapies, we found that just 12 high-level psychological strategies encompass nearly every technique for improving your life.

To learn a lot more: Jeremy and I describe each of these 12 levers in detail in our forthcoming book, The 12 Levers.