Newsletter #97: Flattening the Curve to Slow a Pandemic and Save Lives
Hello Friends!
Welcome to the latest edition of the humanOS newsletter!
Although life goes on, we have been closely following the COVID-19 pandemic, and much of today’s roundup reflects that. We hope that, if nothing else, this strange and nearly-unprecedented situation reminds everyone of how priceless our health is, and that our own health and the health of others is interconnected. We are all in this together. 🙏🏻
Below, as always, is our own content, and a roundup of the various studies and media that captured our attention this week.
This Week’s Research Highlights
🏃 More steps per day is linked to big reductions in relative risk of diabetes and high blood pressure.
Researchers analyzed data from 1923 participants in the national Coronary Artery Risk Development in Young Adults (CARDIA) study. Subjects wore accelerometer devices for at least 10 hours or more per day for a minimum of four days. After an average follow-up of nine years, they found that participants who walked the most steps per day had a 43% lower risk of diabetes and a 31% lower risk of high blood pressure, compared to those with the fewest steps. Among female participants, each 1000-step interval resulted in a 13% lower risk of obesity, and those with the highest step count were 61% less likely to be obese, compared to women who walked the least.
🏌 Increasing physical activity may help older adults live longer, and it doesn’t have to be hard.
Researchers evaluated physical activity levels of 1262 older (average age of 69) participants from the ongoing Framingham Offspring Study. Subjects were instructed to wear a device that objectively measured physical activity for at least 10 hours a day. After follow-up, the participants were 67% less likely to die of any cause if they spent at least 150 minutes per week in moderate to vigorous physical activity. Furthermore, each 30-minute interval of light-intensity physical activities—such as household chores or casual walking—was associated with a 20% lower risk of dying from any cause. Conversely, every additional 30-minutes of being sedentary was related to a 32% higher risk of dying from any cause.
🥑 A daily avocado may boost aspects of cognitive performance.
Researchers recruited 84 adults with overweight or obesity and randomly assigned them either to a daily meal with fresh avocado, or a daily isocaloric meal without avocado (control). After 12 weeks, participants in the avocado group showed improvements in serum lutein levels (as you would expect), as well as improvements in a cognitive test meant to assess attentional control. Interestingly, cognitive benefits were independent of changes in lutein concentrations, suggesting that other components of the avocado may have mediated its influence on cognitive function.
🚴 People who maintain significant weight loss have several influential habits in common - and physical activity is at the top.
Weight loss is not terribly difficult to induce, but maintaining a significantly reduced body weight remains elusive for many. Can we learn from those who have been successful? Researchers analyzed 52 articles corresponding to five different long term weight control registries around the world, and tried to identify common specific factors that were reported to contribute to success in participants. Increased physical activity was the most consistent positive correlate of weight loss maintenance. Other frequently reported habits of successful weight loss maintainers included: having healthy foods available at home, regular breakfast intake, increasing vegetable consumption, decreasing sugary and fatty foods, limiting certain foods, and reducing fat in meals.
🏥 Self-quarantining and social distance save lives by flattening the curve - reducing the burden on healthcare systems.
Leading epidemiological experts estimate that anywhere from 20% to 60% of adults around the world may be infected with COVID-19. However, just because most or even all of us may eventually catch this virus, doesn’t mean that a fatalistic response is justified. Public health officials are advocating for rapid efforts to slow down the transmission of the virus in order to “flatten the curve.”
Basically, we want to spread out the infection rate over a much longer period of time - prolonging the epidemic - in order to ensure that we don’t reach a point where demand for patient care outpaces our capacity (including providers, hospital beds, ventilators, etc.) One of the best ways to flatten the curve is a very old strategy - social distancing. Stay out of crowded public places, avoid mass gatherings, and maintain about six feet between yourself and others.
Videos We Loved This Week
- Michael Osterholm: On the severity of COVID-19, where it came from, and what we can do about it. Via The Joe Rogan Experience.
- Grant Sanderson: Exponential growth and epidemics. Via 3Blue1Brown.
Products We Are Enjoying
Electric kettle
Awesome kettle that I use literally every day to make tea and mate, and which I cannot recommend enough. It’s cheap, easy to use, and is probably the most convenient way to quickly boil water. Additionally, drinking warm liquids might be a smart idea to (slightly) reduce risk of respiratory infection, particularly as it becomes more difficult to prevent exposure in the environment. Regular inhalation of water vapor is thought to help keep the mucus layer of the respiratory tract more fluid, which in turn helps the cilia lining that part of the body to clear out invading particles, including viruses. Just to be clear, I certainly wouldn’t rely on this as a prevention measure ( plz listen to the CDC and wash your hand people) but I’ll take what I can get in a situation where we have limited control. And hey, staying hydrated is always a good idea anyway, right?
New humanOS Course
The Paleo Diet Course - Available now to all Pro users
New humanOS Content
- humanOS Radio: Novel Light Intervention to Fight Social Jet Lag in Teens. Podcast with Dr. Jamie Zeitzer
In this episode of humanOS Radio, we welcome Dr. Jamie Zeitzer back to the show. Jamie is an Assistant Professor in the Department of Psychiatry and Behavioral Sciences at Stanford University, as well as at the VA Aging Clinical Research Center at Stanford.
In our previous interview, we discussed his research on light and timing of biological rhythms. He and his colleagues determined that brief, intermittent flashes of light have a much bigger impact on clock timing than continuous light exposure. This has interesting implications for shift workers, as well as for people who travel across multiple time zones and are subject to jet lag. In theory, you could expose yourself to brief flashes of light while you are asleep, and effectively “trick” your brain into adjusting to a new time zone. Pretty cool.
But could it also be useful for social jet lag - meaning a chronic misalignment between the biological clock and the time when one is forced to be awake and active? In particular, could it be effective for teenagers, who have to get up to go to school at a time when their body is inexorably driving them to sleep?
To answer that question, Jamie and colleagues conducted a randomized controlled clinical trial testing how exposure to brief flashes of light affected sleep onset and total sleep duration in high school students, and the results were pretty impressive. To learn more about the study and what it means, check out the interview!