Newsletter #89: Fueling for Endurance, Yogurt & Arginine, and Tea 🍵
Hello Friends!
Welcome to the newest edition of the humanOS newsletter! Below is our work, plus the assorted studies and media that captured our attention this week. 🤓
Additionally, our good friend and contributor Jeff Rothschild, creator of the humanOS Fasting Program, needs your help. He is conducting a brief online survey as part of his PhD to better understand how endurance athletes, of all levels, fuel prior to workouts. This research will allow relevant lab-based studies to be designed, and provide insights that can be shared with athletes, coaches, and the scientific community by looking into things like how many people train fasted, what their decisions depend on, if this varies by sex or competitive level, etc.
Please click here for more information, and feel free to share with others as well. Every response helps to obtain the most impactful and relevant findings. Thank you! 🙏🏽
This Week’s Research Highlights
🧠 A single night of sleep deprivation may increase blood levels of a biomarker linked to Alzheimer’s disease.
Researchers recruited 15 healthy young men, all of whom reported regularly getting 7-9 hours of quality sleep per night. The study was divided into two phases, in both of which the men were observed in a sleep clinic for two days and nights, under a strict meal and activity schedule. In one phase, subjects were allowed to get a full night of sleep both nights. For the other phase, the participants were permitted to sleep fully the first night, but for the second night they were forced to stay up the whole night. After the night of sleep deprivation, the men showed a 17% average increase in tau levels in the blood. Dysfunction of tau proteins in the brain is thought to play a role in the pathology of neurodegenerative diseases, though the significance of higher blood levels of tau, in the context of sleep loss, is not yet clear.
🧬 Good sleep patterns may partially compensate for the increased risk conferred by high genetic susceptibility to cardiovascular disease.
Researchers examined data from 385292 healthy participants in the UK Biobank project. They analyzed SNPs from blood samples, creating a genetic risk score for cardiovascular disease, and also created a novel “healthy sleep score,” ranging from 0 to 5. Participants were followed for an average of 8.5 years. Compared to those with a sleep score of 0-1 (unhealthy sleep pattern), subjects with a score of 5 had a 35% reduced risk of cardiovascular disease, and a 34% reduced risk of both heart disease and stroke. Those at higher genetic risk who had a healthy sleep pattern were still at elevated cardiovascular risk, but the impact was partly offset. Subjects with high genetic risk and poor sleep pattern had more than 2.5-fold greater risk of heart disease, while those with high genetic risk and good sleep were at roughly 2-fold risk.
🦠 Consuming probiotic-rich yogurt, combined with the amino acid arginine, may boost vascular health and reduce risk of cardiovascular disease.
Healthy individuals with BMI around 25 (at the top of the “normal” range) were randomly assigned to either consume yogurt augmented with Bifidobacterium animalis subsp. lactis (Bifal) and the amino acid arginine, or placebo (just normal yogurt). The researchers used endo-peripheral arterial tone to assess reactive hyperemia index, a measure of vascular function. After 12 weeks, they found that change in RHI in the Bifal + Arg yogurt group was significantly higher than that in the placebo group, suggesting that Bifal + Arg yogurt intake had improved endothelial function. This is likely due to increased production of putrescine, a spermidine precursor, in the gut. It was previously shown that spermidine-induced autophagy reduced blood pressure and cardiovascular risk in an animal model. And in the experimental group of this study, concentrations of fecal putrescine and serum putrescine and spermidine were higher.
🍵 Regular tea consumption has been linked to reduced risk of cardiovascular disease morbidity and mortality.
Researchers analyzed data from 100902 Chinese adults from the Prediction for ASCVD Risk in China project (China-PAR) in 15 provinces across China. Information on tea consumption was collected through standardized questionnaires, and health outcomes were identified by interviewing study participants or their proxies, and checking hospital records and/or death certificates. Subjects were followed for a median of 7.3 years.
Compared with never or non-habitual tea drinkers, those who regularly consumed tea (3+ cups daily) were found to be at 20% lower risk of atherosclerotic cardiovascular disease incidence, 22% lower risk of atherosclerotic cardiovascular disease mortality, and 15% lower risk of all-cause mortality.
Podcasts We Loved This Week
- Samia Mora: Lipids, lipoproteins, and atherosclerosis. Via Sigma Nutrition Radio.
- Amy Bender: Why sleep is vital to your sports and fitness regime. Via Sleep Junkies.
Products We Are Enjoying
Portable dressing containers.
These 2-ounce reusable silicone containers make it easy to pack dressings, sauces, or other condiments for traveling, or even just for meal prep if you’re into that. Also useful for controlling portion sizes, if you’re someone who tends to overdo it when freely pouring dressings and other tasty stuff. They are safe for the fridge, freezer, microwave, and dishwasher, and are BPA free. Also pretty affordable (for some reason the 3-pack is cheaper than the 2-pack on Amazon right now, go figure 🤷).
New humanOS Features
🙌🏽 Course Enhancement: We have added Talking Points to the fourth course (Appetite) in the Ideal Weight Program, created by Stephan Guyenet.
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. No point in studying something if you can’t use that info later, right?
humanOS Catalog Feature of the Week
Want to watch this course with us this week? The first lesson is less than five minutes long. Not yet a Pro user of humanOS? No sweat, this initial module is available for everyone, so give it a shot.