Whether you're dealing with a difficult decision, organizing a complicated project or feeling confused, stressed or anxious about something — or about nothing — try keeping a journal. Not only does journaling offer a number of intellectual, organizational and psychological benefits, but some studies have shown that it can also improve your physical health. And none of these advantages require that you be a good writer.

Artists, writers, psychotherapists and even little girls who are gifted locked pink diaries have long been aware of the importance of journal-writing. But did you know that scientists like Marie Curie and Albert Einstein also kept journals? So did business magnate and philanthropist John D. Rockefeller, General George Patton and Winston Churchill.

And the act of journaling can be as complex or as simple as you want it to be: it's less about the physical object in which you write down your thoughts, or the format your writing takes — let alone if the writing would pass muster with some high school English teacher — than about taking time to externalize your thoughts and feelings without fear of judgment from yourself or anyone else.

For instance, an architect with whom I spoke told me that his journal is far from literary. “It has to-do lists, ideas that come to me while I’m out in the field or even when I’m taking a run," he said. "If I don’t stop and write them down, I forget them.” When he’s out running, he even keeps an index card and pen in his pocket for thoughts that come to him them and, when he gets home, he tapes the index card into the larger notebook.

Another woman with whom I spoke told me that she started keeping journals when her great aunt gave her a locking diary for her sixth birthday, adding, “I used to write down feelings that I couldn’t tell anyone else — when I was really mad at my mother, for example, or hated my best friend, or had a serious crush on a boy." Over time, how she journaled changed, to reflect her own changing emotional needs. These days, she said "I write down everything I can about whatever problem I’m working on. I don’t stop to edit or to correct spelling or grammar: I just write as fast as I can, and I write everything I can come up with."

Get the think newsletter. This site is protected by recaptcha

Unlike in her younger days, she then reviews her problems, and writes down solutions. "Then," she said, "I close the book and wait for an hour or so. Sometimes I figure out what to do while I’m waiting. Other times, I go back and read over what I’ve written. If a solution still doesn’t appear to me, I start a new list of possibilities.”

Problem-solving, expressing hidden or unacceptable feelings, and keeping track of ideas that might be useful as artistic or work-related projects all make sense as reasons to keep a journal. But how can doing so improve your physical health?

The answer seems to be that writing can reduce stress, which can boost your immune system.

For example, in one study, 107 asthma and rheumatoid arthritis patients were instructed to write for 20 minutes on each of three consecutive days: 71 participants were told to write about the most stressful event of their lives; the other 36 were told to write about their plans for the day. Almost all of these patients showed significant objective improvement in their symptoms, although the ones who wrote about stress improved more than the other participants.

Another study conducted with 37 HIV-infected patients had similar results. The people in this group were divided into two groups, one of which was asked to write about negative life experiences and the other about their daily schedules. In this study, those who wrote about life experiences showed a greater improvement in the level of virus in their system, although the improvement did not continue when they were measured four months later. (I wonder, but have no information one way or the other, if this drop-off was at least in part because they were no longer keeping journals.)

The conclusions drawn by both studies were that daily writing about emotionally significant experiences can improve our immune system, probably in a way not totally different from exercise, which is by reducing the chemicals that stress releases in our bodies.

However, many psychotherapists who use journal-writing as part of their work have noted that simply venting emotions is not enough to reduce stress and can, in fact, increase it. You have to actually process those emotions — and that seems to be the key to the significance of journaling. It helps you pay attention and put structure and organization to your thoughts, feelings and ideas that might otherwise be causing anxiety or other stress.

Researchers from Harvard Business School found, for instance, that part of the impact of journaling has to do with paying attention to small details that you might not otherwise notice. James Pennebaker, one of the researchers who studied the impact of writing on HIV-infected patients, said that "By writing, you put some structure and organization to those anxious feelings. It helps you to get past them."

And though, especially for people with anxiety, it can be intimidating to even think about starting a journal, it doesn’t need to be. There are many different ways to journal (and no "right" or "wrong" ones) and many books and articles about how to get started.

In her classic book "The Artist’s Way" — with accompanying workbooks and journals — Julia Cameron encourages people to start with a morning ritual of writing three pages of stream-of-consciousness writing in longhand. Ryder Carroll, the author of "The Bullet Journal Method: Track the Past, Order the Present, Design the Future,” writes that your journal can take any form, even just a simple list of things you have to do today.

Both Carroll and Cameron, however, say that it is important not to be self-critical, and both emphasize that no one else is going to see your journal. For instance, “There is no wrong way to do Morning Pages,” writes Cameron. “They are about anything and everything that crosses your mind — and they are for your eyes only.”

Privacy is, of course, an important part of journaling and, unfortunately, no matter what format you choose, there is always a possibility that someone else might see what you’ve written. If you’d really like to keep your private thoughts to yourself, be very sure that you find a way to keep your journal somewhere that no one else is going to find it. Otherwise, you’re liable to find that journaling increases your stress rather than reducing it.

And that is definitely not the point. If journaling stresses you out, for whatever reason, give yourself permission to take a break — and think about why. Maybe if you have trouble parsing the reasons you'll find yourself... wanting to write them down. Just for you.