Book Review: Stop Overthinking

by Nick Trenton

Published: 2021

Review published: September 2025

What I Learned / My Take

1. Everyone is anxious about something: money, work, families, relationships, growing older, or stressful life events.

2. Is overthinking genetic? Yes—but not only genetic. Life still weighs in on that 74%, meaning environment may play an even bigger role.

3. Our daily habits can feed anxiety and lead to overthinking: frequently checking social media, poor nutrition, not drinking enough water, awkward sleep cycles, etc.

4. To flourish, we don’t need a stress-free environment—we need one that’s optimally suited to our needs.

5. Stress and anxiety are not the same. Stress is external (pressures in the environment); anxiety is our internal experience of those pressures. (Dr. Sarah Edelman)

6. Being alive is stressful: working pressures, demanding children, lack of sleep, too much junk food.

7. If you have an external locus of control (you think life is controlled by luck or other people), you may see new situations as threats instead of challenges. Your reaction becomes anxiety, not excitement.

8. Anxiety is a physiological, mental, psychological, social, and even spiritual phenomenon. It triggers a cascade of neurotransmitters and hormones—the classic fight-or-flight response to a perceived threat.

9. Anxiety can cause nervousness, lack of motivation, depression, feeling out of control, negative thinking, harmful self-talk, lower confidence, and kill motivation.

10. Social and environmental effects include damaged relationships, poor work performance, irritability, social withdrawal, and addictive behaviors. Chronic anxiety robs life of meaning and joy.

11. Your perceptions, sense of self, worldview, and cognitive models determine your interpretation of events. We don’t respond to stress, but to our perception of stress.

12. With the right techniques, we can reframe our perspective and change our behavior, stopping overthinking and putting our brains to good use.

13. Stress is a fact of life—but overthinking is optional! With practice, anyone can retrain their brain to see things differently and resist constant anxiety.

14. Overthinking means excessively analyzing, evaluating, ruminating, and worrying to the point it damages your mental health because you can’t stop.

15. The two main sources of anxiety: genetics and environment.

16. The goal in de-stressing is to pinpoint exactly what’s going on in your head when you overthink.

17. Awareness is not rumination: being aware means noticing both inner and outer experience without judgment or resistance.

18. When stress piles up, it’s overwhelming. You can’t think straight with one crisis after another. But you can always stop, breathe, and notice what’s happening.

19. The first thing: avoid stress. That means saying no to unnecessary and harmful stress—not running away from obligations.

20. When you face a stressful situation, ask: “Can I just avoid this?” If yes, do it. If not, find ways to change or alter it.

21. To accept a situation you dislike, first acknowledge your feelings. Acceptance doesn’t mean pretending—validate your emotions and own them. For example: after a breakup, accept your sadness and share with a friend.

22. Forgiveness is something you do for yourself, not the other person.

23. Adapting to stress means changing yourself to better cope: refuse to engage in depressing thoughts, practice optimism, find ways to make yourself stronger.

24. If all your stress comes from one person, set boundaries in your relationships.

25. If things feel disastrous, force yourself to focus on the single most important thing right now.

26. Know your values. With values in mind, you can decide what’s important and what isn’t, and rank your activities and tasks.

27. Begin each day with your priorities—give them your attention, time, and resources.

28. Put labels on tasks:

• Important & urgent: do immediately.
• Important but not urgent: decide when to do it.
• Not important but urgent: delegate.
• Not important & not urgent: delete!

29. The more you get out of your head, the less you have to worry and overthink.

30. Poor time management is one of the biggest sources of anxiety.

31. Manage and control overwhelming feelings: sit or lie down, use calming self-talk, breathe slowly and steadily.

32. Think of a place that engages all your senses in a pleasant way.

33. Physically relax your muscles by tensing and then releasing them.

34. Mind, body, and emotions are all connected. But for anxiety, the mind plays the biggest role.

35. The key is to take control of anxious thought patterns and consciously replace them with thoughts that help you feel calm, in control, and capable.

36. How we feel isn’t because of what happens, but because of how we think about what happens. When we change our perspective, we change our feelings.

37. Questions to guide your thinking:

• What evidence do I have that my automatic thought is true?
• Are there other explanations?
• Have I made an error or assumption?
• What’s the worst that could happen—and is it really that bad?
• What cognitive distortions am I using? What does the thought look like without them?
• What would I say to a loved one thinking this?
• Have I looked at all the facts or just some?
• Is my response genuine or just a habit?
• Where did this thought come from? Is that a reliable source?

38. Sometimes, beliefs come from past experiences or old habits. The best way to change is to try it out for real.

39. What voice do you use with yourself? Is it positive or negative, accurate or inaccurate, realistic or unrealistic, kind or unkind, helpful or unhelpful?

40. Focus on what you can do, not on what you can’t.

41. Focus on the present, not the past or the future.

42. Focus on what you need, not just what you want.

Scenes and Images that Stuck with Me:

• The spiral of overthinking—where one small worry grows into an all-consuming storm in your mind.
• Stressful environments that seem impossible to escape—until you set boundaries and reclaim control.
• The shift from rumination to awareness: turning inward without judgment and simply noticing your thoughts and feelings.
• The relief of letting go—accepting things as they are, forgiving others for your own peace, and focusing on the present moment.
• The simple act of labeling and organizing your thoughts and tasks to free your mind.
• The calm that comes from controlling your breath, relaxing your muscles, and choosing a new, kinder narrative for yourself.

Would I recommend it?
Yes. If you feel trapped by constant thoughts and worries, this book gives you both understanding and practical tools to quiet your mind and take back your life.