WIL Weekly #44

Testosterone makes men more honest, collagen protects your balls and more...

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1. Testosterone makes men behave more honestly?

April 2023 paper: Testosterone eliminates strategic prosocial behavior through impacting choice consistency in healthy males

“Humans are strategically more prosocial when their actions are being watched by others than when they act alone.”

A 2023 article finds that administering 150mg testosterone “fully eliminates” men’s modifying of their behavior to gain the favor of an audience. A positive spin on eliminating “strategic prosocial behavior” would be to say that the men started to act more honestly. The researchers note that: “Our results are, furthermore, in line with studies showing that testosterone decreases deception.” Another way to put it would be that they stopped caring what others think.

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2. Glycine protects your balls

December 2022 paper: Glycine protects the male reproductive system against lead toxicity via alleviating oxidative stress, preventing sperm mitochondrial impairment, improving kinematics of sperm, and blunting the downregulation of enzymes involved in the steroidogenesis

“It has been found that glycine could attenuate oxidative stress and mitochondrial impairment in various experimental models.”

Lead is known to be highly toxic to the male reproductive system. Male mice were force fed lead (20mg/kg/day) and an amount of glycine that was 10-25x that of the lead (250 and 500mg/kg/day). Then they went and checked out how badly their reproductive system was damaged. They found that the testicles and sperm of the mice given only lead showed significant signs of damage (oxidative stress and sperm mitochondrial function). However, glycine significantly blunted oxidative stress markers in testis and sperm.

“These data suggest glycine as a potential protective agent against Pb-induced reproductive toxicity. The effects of glycine on oxidative stress markers and mitochondrial function play a key role in its protective mechanism.”

Moral of the story: bone broth, knuckles, connective tissue, collagen et cetera protects your balls from oxidative stress.

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3. Got acid reflux? Stop eating so late.

Not only is it well known that eating too late overall disrupts your sleep, it may be a great way to have more heartburn.

Per Circadian rhythms: a regulator of gastrointestinal health and dysfunction:

“…circadian rhythms in the intestine are robustly entrained by the time of food consumption which can override the direction coming from the SCN.”

This means that even though you may feel like you’re on a very consistent circadian clock, if part of your “consistent” schedule includes eating shortly before going to sleep, your digestive system is likely to run on a different clock that is out of sync with your body’s overall rhythm. That is, you might feel like it’s 11PM and time to go to bed because it is 11PM, but your digestive system may think it’s barely 7PM because you finished eating at 8:30PM.

Simply put, acid reflux is what happens when the muscle at the end of your esophagus and start of your stomach opens up at the wrong time and lets stomach acid flow up into the esophagus. This muscle is called the lower esophageal sphincter (LES). The wrong time typically means at night. If you’re laying down, it’s very easy for acid to slosh into the esophagus if the LES opens up.

Evidence suggests that the lower esophageal sphincter is on a circadian clock and that it is natural for the LES to open up during the day. This shouldn’t be much of an issue if you’re sitting or standing upright as we often are during the day. Of course it would not be ideal for the body to suddenly open up the LES when you’re laying down. However, if your digestive tract is getting the wrong signal and assuming that it is daytime, it may also assume you’re still upright and so opening the LES isn’t an issue.

Further, melatonin seems to strengthen the contractility of the lower esophageal sphincter. (Some groups are investigating the therapeutic effect of melatonin in gastro-esophageal reflux disease). This could be another example of the body’s intricate harmonies: Melatonin makes you sleepy but also gives the signal to tighten the LES so you a big splash of acid doesn’t wake you up in the middle of the night.

This suggests that people with acid reflux should really take blue light seriously. Blue light viewing late at night is well known to wreck melatonin production.

If you must eat late at night, don’t.
If you must use your computer late at night, at least get some blue light blocking glasses.

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4. Higher protein intake better for older adults with kidney disease

May 2024 paper: Protein intake and mortality in older adults with chronic kidney disease a multicohort study

Study finds that higher protein intake reduces mortality in older adults with chronic kidney disease, despite the often made claim that protein is “bad” for the kidneys.

“Higher protein intake might have a positive impact on mortality in older adults with mild or moderate CKD, particularly plant protein. Recommendations for these patients may not differ substantially from those without CKD.”

Re: “particularly plant protein” - You’re probably familiar with the healthy user bias by now. I imagine plant protein intake is acting a marker for diet quality rather than conferring some magical effect.

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5. Taurine improves exercise performance?

From a 2021 review titled Taurine in sports and exercise:

Taurine was investigated to evaluate the effects of oxidative stress, aerobic capacity, and maximal workload in untrained males. Subjects performed one VO₂max test then received 2 g three times a day in a powder for 7 days prior to a second VO₂max test. Taurine improved VO₂max (43.7 ± 4.7 ml/kg/min vs. 46.7 ± 5.3 ml/kg/min), exercise time (18.8 ± 3.2 ml/kg/min vs. 19.3 ± 3.4 ml/kg/min), and workload (234 ± 65 W vs. 243 ± 67 W) after 7 days of supplementation. Even though there may have been familiarization between the two tests, taurine concentration levels were positively correlated with changes in time to exhaustion and maximal workload.

Kind of interesting that Peter Attia has talked plenty about how VO2 max is correlated with higher longevity, that taurine has recently (2023ish) been gaining fame as a longevity supplement and Taurine seems to raise VO2 max.