The science behind journaling and its role in better health

Once considered the domain of teenagers’ confessions, keeping a journal has become an increasingly popular practice for supporting your mental health. We dive into the science behind journaling, and how it can form the backbone of a healthy lifestyle.
Simon Lovick
min read
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Quick summary

  • Journaling has been found to have a strong link to supporting your mental health, as well as a number of other physical benefits
  • Keeping a journal can help you form positive habits and identify negative ones
  • It’s a particularly strong method for weight loss, and keeping track of progress
  • Find out how you can start journaling—how often to write, what to include, and more

Keeping journals is a practice dating back thousands of years, having been one of the primary ways that major events were recorded and remembered to this day. Over the years, it has transformed into a more personal habit, a way of jotting down your thoughts, emotions, or deepest secrets.  

Journaling and expressive writing are now considered to have a strong link to your mental and physical health, providing a structure to healthy behaviours and helping you understand and engage with negative emotions. At Habitual, journaling is an important part of the programme and something we believe is an instrumental part of implementing healthier habits. 

Here, we explore the science of journaling, particularly around implementing a healthy lifestyle, and how to get a start on writing your own journal. 

The benefits of journaling

There’s a good chance, at some point in your life, you’ve sat down to put your thoughts to paper. It may have been a one-off, or it may have been part of a longer term journey into journaling. In the UK, just under a quarter of people keep a journal.[1] What you may not have realised at the time, though, is that there are countless benefits to be derived from keeping a journal. 

Journaling has links to improved happiness, sleep, memory function, and personal performance

Many of these benefits are related to your mental health. Keeping a diary has a big impact on your overall happiness,[2] as well as supporting conditions like depression and anxiety. This has a knock-on effect on things like your general stress levels and your quality of sleep. 

There are other cognitive benefits from journaling. For those looking to boost their memory function, the habit of expressive writing has a strong link to increase memory capacity.[3] There’s also a link to personal performance, on account of how self-reflection can help boost your productivity.[4]

Journaling for weight loss

Journaling, or ‘self-monitoring’, is a particularly popular tactic for those looking to lose weight and implement a healthier diet.[5] You may choose to approach this mathematically, calculating your calorie input and output, or through keeping a tally of your balance of protein, fat, carbohydrates, etc. This will help you fully understand which are the healthier, and not-so-healthy, foods that you’re consuming. 

Part of this is to hold yourself accountable for what you’re eating. There’s no possibility of sneaking in a cheeky snack without anyone looking: by recording everything, you’re being fully transparent with yourself about your eating habits. It’s also about being fully honest with yourself, so you aren’t tempted to rationalise away an unhealthy habit. 

It can also help you understand your particular weaknesses or areas that you struggle with. For instance, midnight snacking—if you’re consuming a lot of your calories between 8pm and 12am, you’ll know this is an area you need to put particular effort into. 

On the flipside, it’s a good way of keeping track of your progress, and whether you deserve a reward. This is a crucial part of the process, so make sure you set clear goals for yourself—whether that’s weight loss, calorie intake, or just cutting out particular bad behaviours—and when you achieve them, be sure to celebrate your efforts! 

Understanding the science

The evidence in support of journaling isn’t just anecdotal—it’s rooted in science. Much of our understanding around this comes from studies by Dr James Pennebaker, an American psychologist who explored the emotional and physical health benefits of expressive writing (aka journaling). 

Pennebaker’s first study in the 80s got 15 college students to write for 15 minutes for 4 consecutive days on traumatic or upsetting experiences in their lives. These subjects all saw significant improvements in their mental and physical health, with Pennebaker drawing a significant link between this and the practice of keeping a journal about deep emotional experiences.[6] 

So what is the science behind it? No one has drawn a definitive link, but there are several explanations that indicate benefits. 

There’s a significant link between better mental and physical health, and regular journaling of emotional experiences

Pennebaker and Beall, J Abnorm Psychol

There are obvious therapeutic aspects of keeping a journal. Labelling emotions and acknowledging traumatic events (natural outcomes of journaling) have a known positive effect on people, which is why they’re incorporated into traditional talk therapy. With regards to implementing healthier living, this process can help you identify negative behaviours and build a plan to combat them in the future, making journaling a useful tool in the process of developing healthier habits.

The practice of writing down your thoughts, emotions, as well as your day-to-day activities also gives you a heightened awareness, helping you develop a coherent narrative about yourself and the world around you.[7] The concept of “getting your thoughts in order” may be more than just a saying: this process can help you see your life and other matters with a clearer perspective. For example, if you're struggling with a type 2 diabetes diagnosis, writing down what you understand about the condition can help you make sense of it and even figure out steps you can take to deal with it. With this clarity, you’ll feel able to navigate your everyday life and diagnosis with confidence.

A positive outlook is also linked to increased gratitude, which is often cultivated through journaling. Gratitude, scientist Robert Emmons writes, is “an affirmation of goodness…that there are good things in the world.” This can help you shift towards a more positive holistic outlook on life, and an improvement on how you perceive yourself in the world. People with this outlook are less prone to conditions like depression and anxiety, which in turn will prevent a number of related physical health conditions. As well as shifting your mind towards optimism, gratitude has physical benefits such as higher sleep quality and a better immune system.[8] The psychological impact of type 2 diabetes shouldn't be overlooked and finding ways to incorporate positivity and stress relief into your daily life is an important aspect of managing the condition.

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Tips for starting your own journal 

So you want to start a journal, but you don’t know where to start? 

Firstly, it’s important that journaling is a consistent practice: it can’t just be something you do once or infrequently. Kick things off by writing for 15 to 30 minutes for 3 consecutive days. You may want to keep doing it daily; if you don’t have the time to keep it that frequently, then make sure you dedicate time out of your schedule on a semi-regular basis.

You should write in a personal, private space, where you don’t feel impacted by others around you. A place where you can be alone with your thoughts. 

In terms of what you want to write, this is different for everyone. Some people may find it easy to write down their thoughts, feelings, and emotions; others may need more prompting. Your journal entries may take a variety of forms: bullet points, free flow, gratitude, letter writing. You might even make a template, such as ‘10 things I’m grateful for’ or ‘5 things that made me smile today’. It’s also important to say that journal entries don’t need to be written. They can be vocal (recorded on your phone). They could even be drawings or doodles. 

The key, though, is to have a structure and method. A brain dump may feel cathartic, but it may not actually help with getting your thoughts in order, so won’t be as effective. Think about what you’re writing, as well as what you’re looking to get out of the process—this will keep you focused.

Keeping a regular journal sounds like it might be a time commitment or a chore: but try not to view it like that. Yes, it takes a certain amount of dedication, especially when you may not feel up to writing. So treat it as a time dedicated to your thoughts and health, and as with any sort of exercise, try to be creative. Good luck journaling!


[1] Has the UK lost its inner Bridget Jones? Retrieved 15 February 2022. Accessible here.

[2] Keeping a diary makes you happier. The Guardian. Retrieved 15 February 2022. Accessible here.

[3] Klein, K., Boals, A. (2001). Expressive writing can increase working memory capacity. J Exp Psychol Gen 130(3):520-33. Accessible here.

[4] Di Stefano, G., Gino, F., Pisano, G., Staats, B. (2014) Making Experience Count: The Role of Reflection in Individual Learning. Harvard Business School. Accessible here.

[5] Burke, L, Wang, J, Sevick, M. (2011). Self-Monitoring in Weight Loss: A Systematic Review of the Literature. J Acad Nutr Diet ​​111(1), p92-102. Accessible here.

[6] Pennebaker, J.W., Beall, S.K. (1986). Confronting a traumatic event: Toward an understanding of inhibition and disease. J Abnorm Psychol 95(3):274-281. Accessible here.

[7] Baikie, K., Wilhelm, K. (2018). Emotional and physical health benefits of expressive writing. Adv Psychiatr Treat 11(5):338-346. Accessible here.

[8] What is Gratitude? Greater Good Magazine. Retrieved 16 February 2022. Accessible here.

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