Moving our Mood

We have discussed biological measures of age in this blog previously, so I was interested to find that last month, research examined the relationship between depressed mood and biological aging. For a group of over seven thousand adults in the US National Health and Nutition Examination Survey (NHANES) dataset, researchers calculated the difference between chronological and biological age as estimated from available biomarkers, finding higher depressive symptom  (PHQ-9) scores independently predicted accelerated biological aging, even after adjusting for other confounders such as smoking, and drinking. Since this research was limited to only the relatively small population within NHANES  that carried the necessary biomarkers and survey data, the researchers acknowledged the need to validate the technique against other datasets. 

However, even acknowledging those limitations, there is reassuring consistency here. Previous research from 2022 demonstrated associations between depression and biological hallmarks of aging such as cellular senescence and mitochondrial dysfunction. Even earlier work showed mental-health impacts upon biology, when research on cellular aging from 2014 demonstrated a dose-response relationship between duration and severity of depression symptoms and telomere length. Biological findings such as these are all likely contributors to the striking links between depression and premature mortality found in research from the US, in Germany, and also in Britain. The health and mortality consequences of depression are clearly not, it seems, impeded by national boundaries...

Since affective disorders continue to exert impacts on health and mortality despite existing treatments, an interesting line of research has investigated the consequences of augmenting treatment approaches with physical exercise. One recent study demonstrated a 16-week program of running offered comparable symptomatic benefits to antidepressant medications, whilst providing marked additional benefits for physical health. An even more recent BMJ study considered a wider range of exercises and showed the beneficial effect was proportional to exercise intensity.

While we wouldn’t normally take health advice from sketch comedy, Monty Python’s entreaty to “always look on the bright side of life” seems to have an unexpectedly strong grounding in research, with the benefits of dispositional optimism being found more or less wherever we look. Cultivating such an outlook from an early age seems a good best way to not only blunt the risks from depression, but to gain numerous other benefits besides.

But, of course, there are many for whom the Python's sage advice came too late, and who will, like Samuel Johnson, Winston Churchill and others, have an unavoidable struggle with their own black dog. Depressive symptoms have a self-perpetuating way of discouraging our engagment with physical activities. But it is increasingly clear that we must push in the other direction entirely, embracing whichever forms of exercise we can. Increasing activity levels is a well-supported treatment for depressive symptoms, and very possibly the best way to move our mood, our health and our longevity, in a positive direction.