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. Light is as good as drugs?
In a paper titled Is It Time to Consider Photobiomodulation As a Drug Equivalent?, PhD Tiina Karu lists the various substantial benefits of light or “laser” therapy. This is where you shine red and near-infrared (NIR) light (wavelengths of light from 660 to 905 nanometers) on some part of the body.
In case the idea that our body would react significantly to light, remember that simply shining UVB (280-315 nm) light on your skin has the body create vitamin D.
Some notable effects of laser therapy she mentioned were:
・Reversing depression and anxiety by shining NIR on the forehead.
・Treating spinal cord injuries.
・Reducing the negative effects of Parkinson’s disease.
・Improving functional outcome after surgical intervention to repair injured nerves.
2. Dairy Good
Finally, in 2023, the whole milk for healthy kids act was passed in Washington, restoring the option of whole milk in school nutrition programs. Previously, we were so afraid of the supposed negative health impacts of milk that kids couldn’t even get whole milk in schools. A 2024 paper in Nutrition Research calls into question the shoddy anti-milk claims.
Key points from the study:
Dairy fat intakes are associated with neutral to beneficial cardiometabolic activities
Full-fat dairy intakes have no demonstrated adverse impact on cardiovascular risk
Fermented dairy intakes positively influence lipid profiles
Milk polar lipids contribute to improved blood lipid profiles
Dietary recommendations concerning dairy likely require greater precision
Bovine dairy milk is a nutrient-rich matrix, but consumption of full-fat dairy food varieties has been claimed historically to be associated with poorer cardiometabolic health, a notion often attributed to the saturated fat content. However, continued investigation that includes observational studies and randomized controlled trials (RCTs) provide evidence that favorably supports full-fat dairy foods and their bioactive components on cardiometabolic health.
3. Are vegetable oils (and plant-based diets)de-evolving our brains?
In the 1980’s, Zoologist Professor Michael Crawford analyzed the types of fat in different animals and he discovered that the more DHA the animals’ brains contained, the smarter the animal. Humans and the intelligent marine mammals have exceptionally high DHA levels. (S)
Most current evidence suggests that the DHA-rich human brain required an ample and sustained source of dietary DHA to reach its full potential.
(Per Docosahexaenoic acid and human brain development: Evidence that a dietary supply is needed for optimal development)
The human brain is very rich in DHA and the brain accumulates DHA “aggressively” up to age 18, but accumulates it most aggressively from about half-way through gestation to around two years of age.(S) Further, “functional measures show that infants consuming preformed DHA have improved visual and cognitive function.” DHA, is contained in human breast milk and the DHA content of the breast milk depends on the mother’s diet. Plant sources don’t work - the breast milk of vegans is dramatically lower in DHA than omnivores.
Also, the plant-based “precursor” of DHA, ALA, is practically worthless. A 2014 study found that vegans had half the DHA of omnivores. Supplementing flaxseed oil does not increase DHA level of the breast milk.
Yet another issue with seed oils/vegetable oils (the key source of omega-6 fats in modern diets) is explained in the paper Docosahexaenoic Acid (DHA): An Ancient Nutrient for the Modern Human Brain
The excessive consumption of omega-6 fatty acids in the modern Western diet further displaces DHA from membrane phospholipids. An emerging body of research is exploring a unique role for DHA in neurodevelopment and the prevention of neuropsychiatric and neurodegenerative disorders.
Ruthlessly roasting the intellectually inferior ruminants, Michael Crawford explains in Docosahexaenoic Acid as a Determinant of Neural, Evolution and Hominid Brain Development that decreasing consumption of DHA with increasing consumption of linoleic acid (the primary omega-6 fat in vegetable oils) will literally de-evolve the brain.
In a typical large, savannah mammal, the linoleic acid to DHA ratio is about 30 to 1 whereas the average brain size is only 350 g. This ratio makes the point that where tissue levels of linoleic acid are high and DHA low as in the case of the large land mammals, the brain size relative to the body diminishes: a form of degenerative brain evolution. By contrast, when the linoleic acid is low and DHA is high, you have cerebral expansion as in the case of the Dolphin.
DHA unfortunately isn’t very heat stable so aim for high-quality wild, raw seafood if at all practical. On that note, Japan, which enjoys plenty of DHA-rich seaweed and raw seafood, allegedly has the highest average IQ in the world at 106.49. There are many factors to IQ, but it’s interesting to note that these sources list Okinawa as consuming the least seafood and having the lowest IQ of the prefectures in Japan. (Kyoto ranked #1 in IQ despite but #26 for seafood consumption.)
Weak but fun data point: According to Maruha Nichiro Holdings (a fishery & aquaculture company):
56.4% of the (39) kids who ate fish twice a week passed the entrance exam for their first choice of High School, but only 46.7% of (15) kids who ate fish only once a week (or less) got into their first choice.
4. Ancel Keys mucking up our brains.
Ancel Keys introduced the “lipid-heart hypothesis” in 1953 which says that eating total fat, saturated fat, and cholesterol leads to heart disease and that consuming less fat and cholesterol, and replacing saturated fat with polyunsaturated fat, would reduce serum cholesterol and the risk of heart disease. The lipid-heart hypothesis has been the cornerstone of national and international dietary guidelines to reduce saturated fat and increase “heart healthy” polyunsaturated fats like the omega-6 linoleic acid.(S)
Fun fact: The gain in IQ in the Americas started to slow down right around the time the “heart healthy” US dietary guidelines were introduced. (The Flynn Effect refers to the long sustained increase intelligence and is thought to do with advances in nutrition and health care. Though, it seems to be slowing down and possibly reversing, according to Richard Haier)
5. Praise the sun. It will make you happy
A 2009 study in Environmental Health found that
Among depressed participants, a dose-response relationship was found between sunlight exposure and cognitive function, with lower levels of sunlight associated with impaired cognitive status (odds ratio = 2.58; 95% CI 1.43–6.69). While both season and sunlight were correlated with cognitive function, a significant relation remained between each of them and cognitive impairment after controlling for their joint effects.
A 2023 study looked at interviews with 787 operating room nurses (ORNs) who don’t get much sunlight exposure. “Mental health, sunlight exposure duration, sociodemographic and work-related variables, and chronic diseases were evaluated. The Kessler 10 scale (K10) was used to assess participants’ mental health status, and their sunlight exposure duration was assessed using their self-reports.”
They found that the less sunlight these nurses got, the worse their mental health. “Poor mental health was negatively associated with greater sunlight exposure hours per day (β=−0.378) and sleep regularity (β=−3.341).” Further, their poor mental health was associated with chronic disease.
We’ve heard that your genes can increase your risk for depression. Unfortunately, some people are dealt a poor hand. Doesn’t matter, your genes are no match for the all-powerful and benevolent sun. Another 2023 study found that:
“an average of 1.5 h/day spent in outdoor light was associated with a lower depression risk whatever the degree of depression genetic predisposition.”
Wake up babe, Joseph’s 5 point weekly review #37 just dropped
Great write-up!
And scary, given where the majority of the global population has been at for the past 4 years and where the global agricultural policies are heading.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9654769/
If I'm reading this right then low DHA intake also heavily correlates to increased risk of preterm birth; and a preterm birth also leads to a decreased in content of DHA in the breast milk which further limits the actual DHA intake for the child.