Newsletter #104: Ultraviolet Light, Atomic Habits, and PB2 🌞
Hello Friends!
Welcome to the latest edition of the humanOS newsletter! Below is our work, plus a roundup of the various studies and media that we stumbled upon this week. 🤓
This Week’s Research Highlights
☀️ Ultraviolet light may be an important modulator of the gut microbiome.
Researchers compared diversity and functionality of the gut microbiome of members of the Yanomami of Venezuela and Brazil to urban American counterparts. The Yanomami are a hunter-gatherer group in the Amazon, situated around the equator with minimal clothing and no sunscreen of any type (also no air pollution to block UVB light). Thus, these people are naturally exposed to huge amounts of ultraviolet radiation. The researchers observed that the Yanomami had greater biodiversity, higher Firmicutes and Proteobacteria, and lower Bacteroidetes, compared to Americans, and some of these features were inexplicable based on known diet and lifestyle factors. However, another experimental study testing effects of controlled UVB exposure in a cohort of Canadian adults produced shifts in their microbiota that mirrored those of the Yanomami. This suggests that ultraviolet light may be the cause of some of the distinguishing attributes of the Yanomami people, and that UV light may play a role in the composition of the gut microbiota.
🌳 More trees in urban areas may save lives and yield billions in economic benefits.
Researchers performed a health impact assessment to estimate the annual premature mortality burden for adult residents associated with projected changes in tree canopy cover in Philadelphia between 2014 and 2025. They found that 403 premature deaths could be prevented annually in the city if they could increase tree canopy cover to 30% of the land area, with the greatest proportional benefit to neighborhoods of a low socioeconomic level. This ambitious urban greening effort could also yield an estimated $4 billion annually in economic benefits, in part due to improved health of residents.
🏭 Air pollution may be an important contributor to fatalities caused by COVID-19.
Geoscientists produced a global overview of regions with high and prolonged distribution of nitrogen dioxide pollution, based on ESA satellite data. They combined this data with data on vertical air flow and were able to identify regions in the world with high pollution and relatively low air movement. They then compared this map of pollution hotspots with data on deaths related to COVID-19, particularly in Germany, France, Spain, and Italy. Sure enough, areas with a high number of deaths, like Northern Italy and the Hubei Province, had high levels of NO2 and low vertical air exchange. Somewhat ironically, the recent lockdown has dramatically lowered air pollution in the epicenters of the pandemic - recent data from NASA and ESA indicates that air pollution has been reduced by up to 30% in these areas.
🧬 Higher consumption of ultra-processed foods is linked to shorter telomeres.
Researchers examined food frequency data from 886 participants from the Seguimiento Universidad de Navarra (SUN) Project, as well as measurements of telomere length - a marker of biological age. They evaluated the association between consumption of energy-adjusted ultra-processed food and the risk of having short telomeres. Subjects with a higher (>3 servings per day) consumption of ultra-processed foods had almost twice the odds of having short telomeres, compared to those with the lowest consumption. Notably, participants in this cohort who consumed larger amounts of ultra-processed foods had higher intakes of salt, fats, saturated fats, sugar-sweetened beverages, and processed meats; and lower intakes of fiber, potassium, magnesium, fruits, and vegetables.
📱 Facebook may not be the best thing for your mental health (shocking, I know).
Researchers randomly assigned Facebook users to deactivate their accounts for four weeks in exchange for $102. The treatment group freed up an average of 60 minutes out of their day, spent more time socializing offline, became less politically polarized, and reported improved subjective wellbeing, compared to controls.
Furthermore, their subsequent use of Facebook remained lower than that of controls after the conclusion of the experiment. On the negative side, this self-imposed blissful ignorance meant that their factual knowledge of current events was also diminished.
Podcasts We Loved This Week
- James Clear: Creatures of Habit. Via the Making Sense Podcast with Sam Harris.
- Nick Hiebert: Saturated Fat and Cardiovascular Disease. Via the Nutrivore Podcast.
- Valter Longo: Science, Fasting, and COVID-19. Via the LLAMA (Live Long and Master Aging) Podcast.
Products We Are Enjoying
PB2 (peanut butter powder).
This stuff is just awesome. It’s a ridiculously simple product - just finely ground defatted peanuts - but very versatile. You can use it in smoothies, oatmeal, sauces...or even just by itself mixed with a little water or almond milk. Since most of the oil is pressed out, it is a lot less energy dense than actual peanut butter, but still loaded with protein, fiber, and other nutrients. I see it at grocery stores all the time, so you shouldn’t have any trouble locating some if you want to give it a shot.
