Newsletter #146: Light at Night, Viral Mutations, and Allergy Season 🤧
Welcome to the latest edition of the humanOS newsletter!
This week, we got some insight into how mutations are affecting the physical structure of the coronavirus, potentially for better and for worse. We also learned that greater exposure to artificial light at night is linked to a higher risk of thyroid cancer.
Finally, for those of you whose allergies seem to have gotten worse over time (myself included here 🙋), there may be a very good environmental reason driving this - and it may be getting worse as time goes on.
To learn more, scroll down 👇🏼
This Week’s Research Highlights
🦠 Mutations may be making the coronavirus more infectious - but it could also be its Achilles heel.
Researchers used electron cryomicroscopy to get detailed images of a recent variant form of the SARS-CoV-2 spike protein, which is currently the dominant version of the spike in circulation. They then compared this structure to the original “Wuhan” form of the virus.
When comparing their structures, they determined that the mutated spike had a more open and flexible structure, compared to the original spike, which would enable it to more easily bind to the human cell receptor and thus gain access to our cells (see below graphic). This offers a likely evolutionary advantage, and would explain why this shape has predominated and is so much more widespread in circulation. However, the researchers point out that this open conformation may eventually become disadvantageous, because it renders the surface of the spike protein more vulnerable to antibodies. As more and more people develop protective antibodies - either due to infection or vaccination - this exposed surface area may prove to be a liability for the virus. We shall see.
💡 Exposure to artificial light at night is associated with elevated risk of thyroid cancer.
Researchers examined nighttime light exposure and thyroid cancer incidence in participants in the National Institutes of Health–American Association of Retired Persons Diet and Health Study (n=464371). Light at night exposure was estimated from satellite data linked to residential addresses, and subjects were divided into five groups based on levels of exposure. Thyroid cancer cases were identified through state cancer registries. After adjusting for potential confounding factors, the researchers determined that being in the highest quintile of nighttime light exposure was associated with a 55% increase in risk, compared to those in the lowest quintile. Importantly, when comparing sexes, this association was found to be significantly stronger in women compared to men (81% versus 29%). This mirrors the findings of a recent case-control study which found that subjects who experienced the highest exposure to blue light spectrum at night had a 60% higher risk of developing colorectal cancer, perhaps due to circadian misalignment.
🐝 Allergy seasons really are getting worse in the US - due in large part to climate change.
Researchers compiled pollen measurements from 1990-2018, derived from 60 pollen count stations distributed across North America. They determined that pollen amounts had increased by around 21% from 1990 to 2018, with the greatest increases recorded in Texas and in the Midwest. Additionally, they found that pollen seasons were starting around 20 days earlier than in 1990, and were lasting ten days longer.
This is thought to be because changes to climate are altering the internal timing of plants, causing them to flower earlier and to release higher concentrations of pollen. When the researchers used a series of climate models to test the role of climate change, they found that climate change was the dominant driver in changes in pollen season length, and that the contribution of climate change is accelerating over time.
Question of the Week
🤔 Triscuits are salty, crunchy crackers developed in the US back in 1900, and still quite popular here today. But where does the brand name “Triscuit” come from?
⚡ Answer (also see this old advertisement)
Podcasts We Loved This Week
- Julie Andersen: Could improved gut health help prevent Alzheimer’s? Via the LLAMA Podcast.
- Alan Flanagan: Salt, Sodium, and Health. Via Sigma Nutrition Radio.
- Amy Nordrum: Why did the Texas power grid fail? Via Science Friday.
The humanOS Bookshelf
Merchants of Doubt by Naomi Oreskes and Erik Conway.
Think back to the high profile scientific issues that have dominated public policy debate over the past 60 or so years. The link between tobacco and lung cancer. Climate change. Second-hand smoke. DDT. Acid rain. These may not seem to be obviously connected to one another.
But research has revealed that the same few contrarian scientists, driven by ideological and financial incentives, worked behind the scenes to challenge overwhelming scientific consensus and prevent public interventions against these problems. How did they do it? They engaged in a few common tactics, originally developed from their response to tobacco: "discredit the science, disseminate false information, spread confusion, and promote doubt."
If you’ve ever wondered why it took so long for the government to intervene against tobacco - despite the fact that there was already pretty convincing epidemiological and animal research suggesting it was harmful - this will open your eyes. It is fascinating (and disturbing) from a historical standpoint to consider how much the deliberate misuse of science may have cost us. But aside from that, I think it is also instructive for understanding current and future issues that face us in understanding and communicating scientific consensus. If you study closely the tactics used by these “experts” to obfuscate and create false controversy, for instance, you might find some interesting parallels in the dialogue surrounding scientific issues today.