After I finished my Ph.D. dissertation everything felt really difficult. I wanted to throw a party for myself, but couldn't seem to plan it. I wanted a job, but couldn't get around to looking for one. I wanted to write more blog posts, but each one felt like it took forever. I wasn't quite aware of it at the time, but I do think writing a 150-page paper on 4 years of my research had maxed out my serotonin system. Subsequently I have come across a lot of research on ways to boost serotonin activity. This information would have been really useful at the time, but at least I can share it with you.
As I described in my last post, serotonin is the molecule of will power, of delaying gratification. Decreased serotonin activity can lead to an inability to create and act on well-formed plans. That can mean having difficulty finishing things, or feeling a little down, or getting annoyed easily, or being unable to control your impulses. If you see that in yourself, or a friend, it might mean decreased serotonin activity. In this post I'll explain 4 ways of boosting serotonin activity that don't involve a trip to your psychiatrist or buying "supplements" from some website in your spam folder.
Now as I also explained in my last post, the phrase "low serotonin activity" can mean a number of different things. It can mean your brain is making less serotonin, or has fewer receptors for it, or those receptors just aren't grabbing on to the serotonin very well. It can also mean the serotonin that's made is broken down too soon, or that the serotonin that's squirted out into the synapse is sucked too quickly back into the neuron. Changing any one of these factors can increase (or further decrease) serotonin activity. For example, most antidepressant medications work by blocking serotonin-sucking proteins (i.e. the serotonin transporter), thereby increasing the amount of serotonin that can act on receptors.
If your low-serotonin activity is making you feel too rushed to finish reading blog posts, I'll just spoil the surprise right here and tell you the punch-line. The four ways to boost serotonin activity are sunlight, massage, exercise, and remembering happy events. At this point feel free to return to your stressful life, or keep reading for a more in depth look.
Now if you're really having trouble, go see a psychiatrist, and stop looking for medical advice on blogs. The symptoms I've described above may be signs of reduced serotonin activity, but they may mean more than that, or something else entirely. Furthermore, even if low serotonin activity is the problem, the following activities may not be sufficient. You might also need something else (e.g. psychotherapy, an antidepressant, etc). That can depend, among other things, on your genetics, early childhood experiences, and current life circumstances. I will say though, that even if the following activities are not entirely sufficient, they will move you in the right direction. So without further delay, let's do some serotonin boosting.
Human evolution occurred, for the most part, outside (or we were created outside, whichever you prefer). Back in the early Paleolithic there were fewer LED screens and fluorescent-lit cubicles. People got their light from the sun, which holds three distinct advantages over other forms of light. It has ultraviolet (UV) light, it is much brighter than standard man-made light, and occurs at the appropriate time.
UV always gets a bad rap, because too much of it can lead to skin cancer. However, UV is important because UV light absorbed through your skin produces Vitamin D. Vitamin D plays many roles in your body, including promoting serotonin production. If you're not getting enough Vitamin D from the sun, then drink some milk. Milk has vitamin D added because the government was worried people were spending too much time indoors (damn government keeping me from getting rickets).
In addition to UV, the intensity of the light you're exposed to is also important. Bright light through your eyes also increases serotonin activity (so it's not necessary to get skin cancer in order to be happy). Now maybe you think the lights in your office are bright, but that's just because your eyes are good at adjusting to ambient light. In reality the intensity of light on a bright sunny day (i.e. the number of photons bouncing around) is about 100 times higher than an office. Don't believe me? Look at your lux meter, or just ask your friend who works in a sleep lab, or the one who is a camera production assistant over in Hollywood (oh, don't have one of those? Then just believe me).
For more specific evidence, experiments in rats show the rate of production of serotonin by the brain is directly related to the prevailing duration of bright sunlight. In addition, the serotonin transporter sucks away serotonin the fastest in the Fall and Winter, and is inversely correlated with the amount of light received. Since the serotonin transporter is the thing that most antidepressants block, getting sunlight can have similar effects to antidepressants.
Lastly, timing of the light is also important. You may notice that the sun is only out during the day. Thus, you want to make sure you expose yourself (not in a dirty way) to bright light in daytime, and not at night. Bright lights at night block the conversion of serotonin into melatonin, and melatonin is essential for a good night's sleep.
Several studies have demonstrated the benefits of massage in boosting serotonin. It's not clear to me whether it is massage in particular, or simply physical human contact, but I'm trying to get my girlfriend to give me more massages, so let's focus on that.
One study on massage was carried out on depressed pregnant women. Depression in mothers is particularly concerning, because their depression can affect the baby's activity of various neurotransmitters, including serotonin. The women received massages twice a week from their partners for four months, and their serotonin levels increased by 30%. If you're pregnant, feel free to use that tidbit to score some massages from your partner.
Another study looked at massage on babies of depressed mothers. They massaged 1-3 month old infants twice a week for 15 minutes for 6 weeks. The infants' serotonin jumped 34%. Other studies have shown that massage helps migraine sufferers to boost their serotonin and reduce their headaches. In addition, women suffering from breast cancer also saw large serotonin increases from massage.
Massage increases serotonin, which will likely improve your mood - a happy ending if you will.
In numerous studies exercise has been shown to increase both serotonin production and release. In particular, aerobic exercises, like running and biking, are the most likely to boost serotonin. However, yoga works too (for more neurobiological effects of yoga check out my earlier post).
Interestingly, if you try to do too much exercise, or feel forced into doing it, it may not have the right effect. Recognizing that you are choosing to exercise changes it's neurochemical effect. That may be a result of your ancient instincts - the difference between running because you're hunting something, and running because it's hunting you.
Make exercise an essential part of your routine. The biggest problem with exercise is that when people don't feel like doing it, they don't do it. But sometimes the reason they don't feel like doing it is because their serotonin activity is low, and they'd rather pig out on chips or watch TV. So it's important to go against what you're feeling at the moment, and remind yourself of what's important to you.
4. Remembering Happy Events
This tip may seem the hokiest of all, but is the simplest. All you need to do is remember positive events that have happened in your life. This simple act increases serotonin production in the anterior cingulate cortex, which is a region just behind the prefrontal cortex that controls attention. The same study that found this also showed that remembering sad events decreased serotonin production in the anterior cingulate. Thus, remembering positive events has a two-fold effect: it directly increases serotonin, and also keeps you from thinking about negative events.
Yes, sometimes when you're feeling crappy it's hard to focus on, or even remember, happier times. This is a phenomenon known as "state dependent recall." In fact, one of the biggest problems in major depression is that people can't recall being happy, and only remember being depressed. If you're having difficulty remembering happy events, then talk to an old friend, or look at photographs, or read your diary (or someone else's).
In conclusion, engaging in all of these activities will give a boost to your sagging serotonin system. Unfortunately, the people who probably need it most couldn't even finish reading this article. Or they never even made it to this blog in the first place. So, congratulations! If you're reading this, your serotonin system isn't doing terribly. Even so, you could probably benefit from sunlight, massage, exercise, and remembering happy events. If nothing else, please pass along the info to someone who could use it.
If you liked this article then check out my new book on the neuroscience of depression:The Upward Spiral: Using Neuroscience to Reverse the Course of Depression, One Small Change at a Time
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