A recent study from Penn State University has looked into the association between negative moods like sadness and anger and inflammation.
It's a highly important area of research considering approximately 17 million adults in America have a major episode of depression per year.
This study adds to a growing body of research linking inflammation with negative moods states - particularly big-ticket items like depression and anxiety.
And this area of research becomes even more intriguing considering most mental health issues aren't commonly associated with physical precursors. So any study that attempts to broaden our understanding of how inflammation may express itself holds huge potential value. It could genuinely change the course of so many lives.
So let's delve into this Penn State research paper and see what they found.
What They Did
This research study used the Ecological Momentary Assessment (EMA) tool and blood testing to assess any links between perceived mood and changes in inflammatory markers. More specifically, they anticipated that negative moods would be associated with higher levels of inflammation and positive moods would be associated with lower levels of inflammation.
Two hundred and twenty people between the ages of 25-65 years of age (average age: 46.21 years, standard deviation: 11.12 years) took part in the study.
Sixty-four percent of participants were female (140) and the remaining 36% were male (80). In terms of ethnicity, 62% of participants were Black, 24% Hispanic, and just over 8% White.
Each participant practiced the EMA for two days prior to the official commencement of the study. Similarly, all participants were asked to recall how often they had felt certain emotions during the previous month leading up to the study and to rate them 1 (not at all) to 7 (extremely).
These emotions consisted of 10 positive emotions and 10 negative emotions. The positive items assessed were:
The negative items assessed were:
Once a baseline was established, participants were required to self-report with the EMA five times a day for the next 14 days. Self-reporting consisted of an emotional rating (from "not at all" to "extremely") in nine categories.
The positive categories were:
The negative categories were:
Once all data was collected, each participant had blood drawn and their inflammatory levels analyzed within approximately 3 days of the end of their recording period.
Interestingly, the study controlled for differences in age, gender, and Body Mass Index (BMI). This was based on the findings of another study that found baseline differences in inflammatory levels between certain demographics. Similarly, they also controlled for those with chronic illnesses (increased blood pressure, kidney disease, etc) and use of statin drugs (cholesterol medication) for similar reasons.
What They Found
Overall, the study did not find significant evidence to suggest that negative moods were associated with increased levels of inflammation when the entirety of the data was considered.
However, things were different when looking into the specifics of their results. They found that negative moods reported closer to the drawing and analysis of blood samples (approximately within one week) were associated with higher levels of inflammation.
They found no correlation between recalled emotional moods and inflammation.
As with any study, it's important to consider its limitations. Otherwise we have no context from which to extrapolate these findings.
The most important thing for me here was that this study did not account for chronic mental illnesses like depression. The study noted that 22% of its participants had at least moderate depressive symptoms but did not control for it or anti-depression medication. It goes without saying that anyone already suffering from a chronic negative mood state can influence their mood with medication. This may have altered the reliability of the results. In a perfect, albeit inhumane world, it would have been best to test all participants in a drug-free environment. This would have given a clearer indication of any links between mood and inflammation.
Like all studies, the characteristics of its participants need to be taken into account. Considering over two-thirds of the participants were Black, it may suggest that these results are less applicable to other races in isolation based on subtle differences in physiology. Similarly, all participants were over the age of 25, so it may make it a little tricky to apply these results to teenagers.
What It Means For You
All things considered, it makes sense that inflammation could be paired with negative mood states. After all, it might just be an emotional expression of deeper physiological stress. It may be a variation on the more easily attributable factors like pain, reddening, swelling, etc.
If the official manual for the human body referenced a real link between negative mood and inflammation, then it gives so many people hope. Any true connection would mean that focusing on reducing inflammation would lead to an improvement in mental health for millions upon millions of people. It could genuinely re-shape the world as we know it.
Furthermore, it gives us reason to invest in simple, natural anti-inflammatory behavior. It might help us invest more energy into avoiding inflammatory foods and beverages like junk food and alcohol, or seeking cleaner, fresher, and less polluted air. It might prompt us to enjoy a cold shower more often, stay better hydrated, practice deep breathing, or even cultivate healthier sleep habits.
At the end of the day, we could probably be doing these anyway, but for those with considerable mental health challenges, it might just provide the spark needed to regain some control and find a potential way out.
Ultimately, I think there needs to be far more research into this topic. As a Physical Therapist, I see first hand the negative mood states in those with inflammation. Whether it's due to injury, chronic pain, and illness, or other factors completely, there's potentially a clear link in there somewhere.
Interestingly, the potential results of this study also raise another question.
Which comes first? Does inflammation cause negative moods, or do negative moods create a more inflamed physiological environment? Instinctively I'd imagine its the former, but I wouldn't be surprised if its a vicious cycle.
So, if you're battling mental health issues or feel more negative than your usual self, firstly, hang in there, but more importantly, consider incorporating more anti-inflammatory behaviors into your day. If the results of this study have found a genuine link between negative moods and inflammation then its worth re-assessing your lifestyle choices. After all, most are free, safe, and simple to do.
Why not see what happens?
Further more, let me know how you're going in the comments below. Does this study give you pause for thought? Does it resonate with how you feel?