Newsletter #196: How Stress Can Literally Kill âĄïž
Welcome to February, humanOS friends! Hope everyone is staying safe and cozy in the face of this winter storm. I was pretty worried about losing power here đ but it looks like weâll be okay here after all.
So, a thought-provoking article in JAMA Psychiatry came out this week that explored the recent increase in âdeaths of despairâ in the US, meaning deaths due to suicide and drug poisoning. Deaths that generally occur when people feel that they have no path forward. This is obviously a complex phenomenon, but one of the explanations provided by the authors is that modern life tends to be simultaneously very predictable and very isolating. This stands in stark contrast to the dynamic environment and the close interdependence that we observe in hunter-gatherer societies, and which mirrors the conditions of the world in which we evolved. Now, this loss of day-to-day stimulation (and danger) isnât all bad. In fact, you could argue that much of our ability to specialize and make progress hinges on being able to work in quiet, safe conditions without a ton of distractions. But it also makes our daily lives less rewarding, and in turn might render us more vulnerable to the reliable dopamine surges offered by drugs and addictive behaviors.
That made me think about just how very different the modern industrialized world is, as well as the types of risks associated with it. Most of us are never confronted with mortal peril, the way that we might be if we lived in a more ânaturalâ setting, accompanied by predators and other environmental threats. But that doesnât mean that our lives are free of stress. Far from it! In fact, itâs worse in some respects, because instead of a short-lived stress response in the face of great danger, we are riddled with chronic stress. And, as Robert Sapolsky demonstrated in his iconic book, this kind of emotional stress can exact a physiological toll. As some of the studies below show, psychosocial stress can lead to increased risk of cancer and cardiovascular disease. It may even make you more likely to become infected with a virus, something that looms on all of our minds right now.
Scroll on down to learn some more about the medical consequences of stress đđ»
This Week's Research Highlights
High lifetime work-related stress is associated with greater risk of some cancers.Â
Researchers in Montreal interviewed 3103 individuals with cancer and 512 population controls (meaning otherwise similar people without cancer as a comparison group). Participants described in detail every job held during their lifetime and stress associated with these jobs. Prolonged exposure to stress at work was shown to be linked to greater odds of cancer at five sites. Specifically, employment in at least one stressful job resulted in 33% increased odds of lung cancer, 51% increased odds of colon cancer, 37% increased odds of bladder cancer, 52% increased odds of rectal cancer, and 53% increased odds of stomach cancer.
High stress is linked to higher risk of having a heart attack or stroke.Â
Researchers at the University of Gothenburg examined data from 118706 participants in 21 countries. So, lots of participants in contrasting cultures, which is always nice. Participants were assessed for their level of psychosocial stress through questionnaires, and followed for an average of ten years. As levels of stress increased, risk of cardiovascular events and death rose as well. Specifically, participants who had reported high stress had 22% higher risk of any form of cardiovascular event, 24% higher risk of heart attack, and 30% higher risk of stroke. One major strength of this study is timing - stress levels were measured before any cardiovascular events, in contrast to studies like the one for cancer described above.
Stress may increase susceptibility to respiratory infection.Â
I know we touched on this topic a while ago, but it is worth revisiting. (It is certainly timely, right?) Anyway, in this study, 394 healthy subjects completed questionnaires assessing levels of psychological stress, and then were administered nasal drops containing either a respiratory virus or saline. Subjects were quarantined and monitored thereafter. The rate of respiratory infection increased in a dose-dependent manner with levels of psychological stress, meaning the more stressed they were, the more likely they were to become sick. This may be due to a phenomenon known as glucocorticoid receptor resistance. Basically, chronic elevations in cortisol, due to stress, make tissues in the body less sensitive to the anti-inflammatory effects of the hormone, which also amplifies the risk for an exaggerated inflammatory response when you fall ill.
Random Trivia & Weird News
đ„ Hamsters are remarkably tolerant of alcohol - it is nearly impossible to get them drunk.
Researchers at the University of Alaska-Anchorage, interested in learning about alcohol metabolism in hamsters, experimented with different doses of alcohol to see if they would eventually succumb to intoxication. They found that the rodents did not show signs of impairment even at 7.5 g/kg - a lethal dose for most humans.
Notably, the hamsters did become drunk when alcohol was injected directly (bypassing the liver). This suggests that the reason why these critters can hold their liquor so well is that their livers are exquisitely efficient at processing ethanol; so much so that not much makes it into their bloodstream.
Podcasts We Loved This Week
- Noah Baker and David Adam: The true death toll of COVID-19. Via Nature Podcast.
- Rosemary Mosco: Pigeons are more than pests. Via Science Friday.
Products We Are Enjoying
YnM Weighted Blanket + Duvet Covers
Weighted blankets have attracted a ton of hype, but there may actually be something to them. A little while ago, researchers had patients with insomnia randomized to sleep for four weeks at home with either a chain-weighted blanket or a light plastic chain blanket (control). 42.2% of the weighted blanket group achieved remission (meaning a score of seven or less on the ISI scale), compared to just 3.6% in the control group. And when subjects were given the opportunity to use the weighted blankets for a 12-month follow-up phase, 92% of weighted blanket users positively responded to the intervention, with 78% achieving remission from insomnia. Wow! If you have trouble sleeping, this is a pretty low-risk thing to try. Plus thereâs just something nice about being gently squished by a heavy blanket.