WIL Weekly #56
What might be killing your dopamine, The Low Calorie High Lifespan myth and more...
This is my free weekly newsletter covering 5 interesting points from the week. Subscribe (if you haven’t already) if you’d like to get it in your inbox each week!
1. Meat-eating warrior or carb addicted wuss?
The Huns apparently had a diet very similar to that of the Mongols. Sure, they were the bad guys in Disney’s Mulan …but they were built like brick walls.
Here’s an interesting passage from Jack Weatherford’s Genghis Khan and the Making of the Modern World
“The Chinese noted with surprise and disgust the ability of the Mongol warriors to survive on little food and water for long periods; according to one, the entire army could camp without a single puff of smoke since they needed no fires to cook. Compared to the Jurched soldiers, the Mongols were much healthier and stronger. The Mongols consumed a steady diet of meat, milk, yogurt, and other dairy products, and they fought men who lived on gruel made from various grains. The grain diet of the peasant warriors stunted their bones, rotted their teeth, and left them weak and prone to disease. In contrast, the poorest Mongol soldier ate mostly protein, thereby giving him strong teeth and bones. Unlike the Jurched soldiers, who were dependent on a heavy carbohydrate diet, the Mongols could more easily go a day or two without food.”
2. Shining red/near infrared light on the head increases cognition and brain growth factors
A 2024 randomized controlled trial from just this month found that applying red/near-infrared light to the head improves cognition and brain-growth factors in the brain.
93 older adults individuals with mild cognitive impairment were randomly assigned to either transcranial photobiomodulation (t-PBM) or placebo group. 76 completed the study.
“The t-PBM significantly improved cognition as measured by the Montreal Cognitive Assessment (MoCA) compared to placebo (p = 0.0301). …This effect persisted until the three-month follow-up, accompanied by increased BDNF levels in the t-PBM group but not in the placebo group (p = 0.0046).”
On that note, a 2018 study on elderly people in Northeast China found that “long-term high sun exposure is positively related with better cognitive functioning.”
3. Caloric restriction boosting longevity is a scam?
2021 study: Rodent diet aids and the fallacy of caloric restriction
A 2021 paper calls into question the utility of rodent studies on longevity. They point out that, as you may expect, not being obese will significantly increase your lifespan. Several studies have shown that caloric restriction can delay aging. However, many studies give mice unlimited access to food and they suffer obesity. So what may seem like health gains from caloric restriction may actually just be these rodents setting themselves apart from their often obese peers. That is, the “health gains” may entirely come down to the avoidance of obesity.
They also point out that these pills and potions that seem to increase lifespan like resveratrol, rapamycin, nicotinamide mononucleotide and metformin also reduce body weight. So, the health gains from these substances may also just come down to helping the animal avoid obesity.
“In primates, CR does not delay aging unless the control group is eating enough to suffer from obesity-related disease. Human survival is optimal at a body mass index achievable without CR, and the above interventions are merely diet aids that shouldn’t slow aging in healthy weight individuals.”
They conclude that
“Caloric restriction in humans of optimal weight can safely be declared useless, since there is overwhelming evidence that hunger, underweight and starvation reduce fitness, survival, and quality of life.”
4. Soy makes you an angry loner?
“Estrogen produced by aromatization of gonadal androgen has an important facilitative role in male-typical aggressive behavior that is mediated through its interaction with estrogen receptors (ER) in the brain.”
Dr. Ari Berkowitz explains in a Psychology Today article that perhaps unexpectedly, “brain estrogens often play a larger role than brain testosterone in regulating aggression.”
A 2008 study found that estradiol rapidly increased aggression when mice were put in housing that mimicked winter-like short days.
Keep that in mind in light of the results of a 2004 study looking at soy supplementation’s effect on adult male macaques…
They found that soy isoflavone-rich diets fed to the macaques for 15 months increased the frequencies of intense aggressive behavior by 67%. Further, they reduced their physical contact with other monkeys by 68%, they reduced their time around other monkeys by 50% and their time spent alone increased 30%. In short, the study found that “long-term consumption of a diet rich in soy isoflavones” made these monkeys angry loners.
5. Maybe you don’t need a dopamine detox, you just need to reduce artificial light?
2020 study: A New Threat to Dopamine Neurons: The Downside of Artificial Light
The other day, I was wearing my blue light blocking glasses while working indoors in the middle of the day and swore I had better focus. Research on the acute effects of artificial light is harder to find, but an interesting study from 2020 implicates artificial light in the development of Parkinson’s disease. Parkinson’s disease is characterized by the degeneration of dopamine neurons in the brain. This 2020 study explains that “prolonged exposure of rodents and birds to fluorescent artificial light results in an increase of neuromelanin granules in substantia nigra and loss of dopaminergic neurons.”
A 2020 paper explains that “aberrant dopamine receptor signaling and abnormal dopaminergic nerve function is implicated in several neuropsychiatric disorders, including Parkinson’s Disease and ADHD.” People with Parkinson’s disease have troubles with attention - difficulty paying attention to one thing and difficulty ignoring distractions. Interestingly, people with ADHD have a 2.6-fold risk of developing Parkinson’s.
This makes me wonder if difficulties with attention span and/or compulsion to doomscroll could be ameliorated by less exposure to artificial light, particularly blue light.
At the risk of sounding hyperbolic, this newsletter is like Christmas morning with all its goodies. Thanks Joseph for mining that Genghis Kahn gem. It shows the powerful impact of the true ancestral diet (carnivore). The piece on red/NIR: interesting that these two light types are lumped together in the study because red light has no heat (most red light devices are consistently cool LED products), while Infrared is inherently heat-emitting). Let's hear it for photobiomodulation! The great thing is, unlike UV, infrared can penetrate several inches (including through a winter coat), so just being outdoors is a win (especially 3 hrs after dawn or 3 hrs before dusk). . . Btw I always questioned the caloric restriction idea, as fruit fly and worm research can't be automatically extrapolated to complex humans. Besides, long term CR can reduce muscle mass, a marker of longevity! Thanks for the dopamine piece; when I saw that, I dimmed my screen a few notches and vowed to not stare at my screen excessively (even if in search of health information-haha).
I can't even pick an article, I love them all!