Newsletter #83: Ice Baths, Frequent Tooth Brushing, & Meat Controversy
Hello Friends!
Welcome to the latest edition of the humanOS newsletter! 🤓 Here, as always, is where we share our work, plus the various studies and media that caught our attention this week.
This Week’s Research Highlights
🧊 Ice baths may interfere with training adaptations.
Researchers had twelve healthy young men perform a single resistance exercise. After each exercise session, the subjects’ legs were immersed in water for twenty minutes. One leg was immersed in cold water (8°C) while the other leg was immersed in thermoneutral water (30°C). The researchers measured muscle protein synthesis rates through stable isotope tracers and muscle biopsies. After two weeks, they found that cold water immersion during recovery reduced muscle protein synthesis rates - which in theory could impair muscle conditioning.
🧠 Low-grade inflammation is linked to mental sluggishness.
Researchers took 20 healthy young men and randomly assigned them to receive either a saline injection (placebo control), or an injection of Salmonella typhoid vaccination, the latter of which to induce a state of mild inflammation. Inflammation levels were measured by assessing IL-6 levels in blood samples. Participants then had brain activity monitored in the lab via EEG while performing a battery of cognitive tests. The researchers found that acute low-grade inflammation was related to a slowing in the brain’s visual processing. People afflicted with systemic inflammation may have to work harder and exert more cognitive effort to maintain attention-related performance.
🦷 Excellent oral hygiene may help preserve heart health.
Researchers examined data from 161286 middle-aged participants of the Korean National Health Insurance System aged 40 to 79 with no history of atrial fibrillation or heart failure. Participants underwent a routine medical examination between 2003 and 2004, in which information was collected about oral health and hygiene behaviors. Tooth brushing three or more times a day was associated with a 10% lower risk of atrial fibrillation and a 12% lower risk of heart failure over a 10.5-year follow up. The findings were independent of a number of factors including age, sex, socioeconomic status, exercise, alcohol consumption, body mass index, and comorbidities such as hypertension. It is thought that frequently brushing teeth reduces bacteria in the subgingival biofilm, which in turn prevents translocation into systemic circulation where they can cause trouble.
New humanOS Updates
- Daily Quotations: We have added inspirational quotations to the humanOS Dashboard. If you wanna check it out, go to the dashboard and scroll down to “Add Tiles,” and add My Motivators (under Tracking and Tools). Every day, a new quote will appear under your motivators.
- Course Enhancement: We have added Talking Points to the first and second courses of the Ideal Weight Program. 🙌
FYI: Talking Points is a feature that is unlocked once you complete a course (just click on the achievement badge), and offers a useful recap of key takeaways from the lessons to aid memory retention, and hopefully enhance your ability to use that information and convey it to others.
New humanOS Content
On this episode of humanOS Radio, Dan talks to Michael Hull. Michael has an MSc in human nutrition from McGill University, and works as a full-time senior researcher at Examine.com.
You might remember that back in October, a series of studies were published that addressed the impact of red and processed meat consumption on a number of health outcomes. Importantly, these papers did not present any new evidence on the subject. Instead, they summarized the findings of existing RCTs and observational studies, and concluded that adults should continue consuming red and processed meat at current levels of intake - an obvious contradiction of most established guidelines. This, naturally, elicited a lot of turbulence online, from all across the diet spectrum.
So, who’s right? Mike wrote an excellent piece for Examine.com sorting out these studies, and was kind enough to come on the show to discuss the papers and their implications. As you’ll see, this is arguably less a discussion of the health effects of meat per se, and more about the aforementioned difficulties in performing nutrition studies and interpreting research. To learn more, check out the interview!
Podcasts We Loved This Week
- Keith Baar: How To Live Longer, Stronger & Healthier. Via the Legendary Life Podcast with Ted Ryce.
- Meeta Singh: Sleep and Circadian Disruption in Pro Athletes: Dealing with the NBA Schedule. Via Sigma Nutrition Radio with Danny Lennon.
Products We Are Enjoying
Good Foods Plant-based Queso
This dip is tasty and versatile - I put it on just about anything that I’m eating. It’s a very simple product, made primarily out of cauliflower, bell pepper, and almonds, and it’s pretty healthy (just 45 calories per 30 gram serving). The company makes some other dips and dressings and other stuff that are also decent. I found this at Target, but they’re at some other stores if you look around or search the company site.
humanOS Catalog Feature of the Week
Want to watch this course with us this week? The first lesson is just a little over two minutes long. Not yet a Pro user of humanOS? No sweat, this initial module is available for everyone, so give it a shot.