Newsletter #76: Flavonoids for Brain Health and Happiness 🍓
Hello Friends!
Welcome to the latest edition of the humanOS newsletter! Here is where we share our work, plus the various studies and media that caught our attention this week. 🤓
This Week’s Research Highlights
🧠 Being hungry may alter your decision-making - even for non-food outcomes.
Researchers tested 50 participants in a delay-discounting choice task on one occasion when they had eaten just two hours earlier, and on another occasion when they had fasted for at least ten hours. When participants were fasted, they expressed a stronger preference for hypothetical rewards that they would receive immediately, rather than larger ones further into the future. This trend applied not just to food rewards, but also incentives that were entirely unrelated to food. The impact was significant. Researchers noted that people are typically willing to wait 35 days to double a given reward in the delay-discounting choice task. But for these hungry participants, this dropped all the way down to three days.
👃🏻 Sleep deprivation makes you more likely to choose fattening foods due to changes in brain connectivity and how the brain responds to food smells.
Researchers recruited 29 healthy young men and women and had them visit the lab once after a normal night’s sleep, and also after a night of only four hours of sleep (each session separated by four weeks). During the lab session, subjects were served a controlled menu of meals, but also offered a buffet of snacks. After being sleep deprived, subjects chose foods with higher energy density, like doughnuts and potato chips. They also exhibited higher blood levels of 2-OG, an endocannabinoid associated with feeding behavior and response to odors. Finally, subjects were placed in an fMRI scanner and presented with a series of odors. The sleep deprived group showed reduced connectivity between the piriform cortex and the insula. This altered connectivity was associated with changes in food choices.
🏋 Metformin blunts muscle hypertrophy in older adults.
In a double-blind trial, researchers randomly assigned healthy older participants to receive either 1700 mg/day of metformin or placebo for 14 weeks. During the study period, all subjects performed supervised progressive resistance exercise training. Compared to subjects taking metformin, the placebo group gained more lean body mass. CT scans showed that increases in thigh muscle area and density were greater in placebo. Metformin users showed a trend for blunted increases in mTORC1 signaling in response to the exercise regimen, potentially decreasing muscle protein synthesis. (To learn more about how metformin may interfere with health benefits of exercise, please check out this podcast with Dr. Ben Miller!)
🍿 Going out to eat may increase your exposure to harmful chemicals.
Researchers analyzed data from 10106 NHANES participants who had provided blood samples analyzed for levels of per- and polyfluoroalkyl substances (PFAS). The researchers found that people who ate more meals at home (primarily from food purchased at grocery stores) had significantly lower levels of PFAS in their bodies compared to those who consumed more food from restaurants and fast food joints. Food at restaurants is more likely to be contaminated with these chemicals, likely from greater contact with food packaging that contains PFAS. Microwave popcorn was also a major offender, due to chemicals leaching out of popcorn bags.
New humanOS Content
- humanOS Radio: Flavonoids and Brain Health. Podcast with Dr. Pamela Maher
In this episode of humanOS Radio, Dan speaks with Pamela Maher. Dr. Maher has a Ph.D. in biochemistry from the University of British Columbia, and currently works as a research scientist at the Salk Institute for Biological Studies.
Her current work is focused on using natural products such as flavonoids to maintain nerve cell function in the presence of toxic insults. One of the great advantages of these phytochemicals is that they are tiny molecules - small enough to cross the blood-brain barrier. This has been convincingly demonstrated in studies of rodents. For instance, when rats are fed blueberries for ten weeks, and then dissected, anthocyanins from the fruit can actually be found distributed inside the brain!
Maher and her colleagues have been focusing their attention particularly on a few of these flavonoids as potential neuroprotective agents. One of these isfisetin, a flavonoid that is most highly concentrated in strawberries, which we’ve discussed previously. Maher and her group have been developing more potent and more bioavailable versions of the flavonoid that might protect nerve cells and even promote learning and memory. Good stuff! Another phytochemical addressed on this show issterubin. Sterubin is a flavonoid found inYerba santa, a plant that native tribes in California have long prized for its medicinal properties. When Dr. Maher screened for plant extracts that could act on toxicity pathways relevant to age-associated degenerative disease, sterubin emerged as one with broad protective effects in cell assays.
To learn more about the power of flavonoids and the future of anti-aging research, please check out the interview!
Podcasts We Loved This Week
- Meeta Singh: Athletes and Sleep. Via Sleep 4 Performance.
- Robert Meadows: Exploring a Sociology of Sleep. Via Sleep Junkies Podcast.
Products We Are Enjoying
Electric kettle.
If you are a tea aficionado like me, this is an absolutemust- I use this kettle every single day. It’s cheap, easy to use, and is probably the most convenient way to quickly boil water. I keep it plugged in close to my workstation so I can make mate, green tea, etc. at a moment’s notice. Particularly helpful when the days get short and chilly. 🍵 🌥