Recent quotes:

Study questions the role of vitamin D2 in human health but its sibling, vitamin D3, could be important for fighting infections -- ScienceDaily

"We have shown that vitamin D3 appears to stimulate the type I interferon signalling system in the body -- a key part of the immune system that provides a first line of defence against bacteria and viruses. Thus, a healthy vitamin D3 status may help prevent viruses and bacteria from gaining a foothold in the body. "Our study suggests that it is important that people take a vitamin D3 supplement, or suitably fortified foods, especially in the winter months." Although some foods are fortified with vitamin D, like some breakfast cereals, yoghurts, and bread, few naturally contain the vitamin. Vitamin D3 is produced naturally in the skin from exposure to sunlight or artificial ultraviolet UVB light, while some plants and fungi produce vitamin D2. Many people have insufficient levels of vitamin D3 because they live in locations where sunlight is limited in the winter, like the UK. The Covid-19 pandemic has also limited people's natural exposure to the sun due to people spending more time in their homes.
#sunlight #vitamin-d - sciencedaily.com

New findings on ambient UVB radiation, vitamin D, and protection against severe COVID-19 -- ScienceDaily

Researchers found that ambient UVB radiation at an individual's place of residence preceding COVID-19 infection was strongly and inversely associated with hospitalisation and death. This suggests that vitamin D may protect against severe COVID-19 disease and death.
#coronavirus #sunlight #UV - sciencedaily.com

Seasonal variation in daylight influences brain function -- ScienceDaily

"In the study, we observed that the number of opioid receptors was dependent on the time of the year the brain was imaged. The changes were most prominent in the brain regions that control emotions and sociability. The changes in the opioid receptors caused by the variation in the amount of daylight could be an important factor in seasonal affective disorder," says Postdoctoral Researcher Lihua Sun from the Turku PET Centre and the University of Turku.
#depression #circadian #sunlight #emotion - sciencedaily.com

Working outdoors linked to lower risk of breast cancer among older women: Outdoor workers are able to make more vitamin D which may be protective, say researchers -- ScienceDaily

In these women occupational exposure for 20 or more years was associated with 17% lower odds of a breast cancer diagnosis while the highest level of cumulative exposure was associated with 11% reduced odds.
#sunlight #cancer - sciencedaily.com

Vitamin D may help prevent a common side effect of anti-cancer immunotherapy -- ScienceDaily

The study included information on 213 patients with melanoma who received immune checkpoint inhibitors between 2011 and 2017. Thirty-seven (17 percent) of these patients developed colitis. Sixty-six patients in the study (31 percent) took vitamin D supplements before starting treatment with immune checkpoint inhibitors. Patients who took vitamin D had 65 percent lower odds of developing colitis, after adjustments for confounding factors. These findings were validated in another group of 169 patients, of whom 49 (29 percent) developed colitis. In this validation group, use of vitamin D was linked with 54 percent lower odds of developing colitis.
#sunlight - sciencedaily.com

Light effects on circadian and homeostatic regulation: alertness increases independent of time awake. | bioRxiv

Results reveal (1) stable free-running cortisol rhythms with uniform phase progression under both light conditions, indicating that FD designs can be conducted under high intensity lighting, (2) subjective alerting effects of light depend on elapsed time awake, while (3) light consistently improves objective alertness independent of time awake. Three dimensional graphs reflecting light induced alertness improvements depending on wake duration related variation and circadian clock phase suggest that performance is improved during daytime, while subjective alertness remains unchanged. This suggests that light during office hours might be beneficial for performance, even though this may not be perceived as such.
#sunlight - biorxiv.org

Adjunctive Bright Light Therapy for Bipolar Depression: A Randomized Double-Blind Placebo-Controlled Trial | American Journal of Psychiatry

In seasonal affective disorder (27, 28) and nonseasonal depression (29), the response to morning light therapy is typically attributed to the phase-resetting effects (28). However, the mechanism of response is unclear in bipolar disorder. Combined with a prior night of sleep deprivation, morning (and possibly midday) light therapy can quickly reverse severe bipolar depression in carefully supervised chronotherapeutic protocols (30–32). Compared with morning light therapy, implementing bright light therapy at midday induced robust antidepressant effects and possibly subtle effects on the circadian system (12, 13) that might have mitigated the risk for hypomania or mixed symptoms, as observed in our earlier report (5). But whether the circadian effects of midday light therapy are detectable in bipolar depressed patients and correspond with an antidepressant response requires further investigation. Even so, this novel finding of a significant antidepressant effect from midday bright light therapy offers a real clinical advance and contributes an additional treatment option for bipolar depression.
#depression #paleotherapy #sunlight - ajp.psychiatryonline.org

Fat cells can sense sunlight—not getting enough increases metabolic syndrome risk

In the latest findings, the research team studied how mice respond when exposed to chilly temperatures—about 40° F. They already knew that mice, much like humans, use both a shivering response and an internal fat-burning response to heat themselves. Deeper analysis revealed that the internal heating process is compromised in the absence of the gene OPN3 and exposure specifically to a 480-nanometer wavelength of blue light. This wavelength is a natural part of sunlight but occurs only in low levels in most artificial light. When the light exposure occurs, OPN3 prompts white fat cells to release fatty acids into the bloodstream. Various types of cells can use these fatty acids as energy to fuel their activities. But brown fat literally burns the fatty acids (in a process called oxidation) to generate heat that warms up the chilly mice. When mice were bred to lack the OPN3 gene, they failed to warm up as much as other mice when placed in chilly conditions. But surprisingly, even mice that had the correct gene failed to warm up when they exposed to light that lacked the blue wavelength.
#paleotherapy #sunlight #fat - phys.org

Fountain Portal

The bones of those who fell on either side in this battle lay scattered separately. The bones of the Persians lay in one part of the field and the bones of the Egyptians in another, as the two armies had separately stood. The skulls of the Persians were so fragile that a mere pebble thrown at them would penetrate them. But those of the Egyptians were so strong that you could hardly break them with a stone. The cause of this, so the people said, and I readily agreed, is that from childhood the Egyptians shave their heads, and the bone is thickened by exposure to the sun. For the same reason they do not become bald. Of all races of men bald heads are rarest among the Egyptians. Such then is the reason for their strong skulls. And the reason why the Persians have weak skulls is that they cover their heads all their lives with felt hoods, called tiaras by the Persians.
#sunlight #UV #bones - fountainportal.substack.com

Comparison of the effect of photobiomodulation therapy and Ibuprofen on postoperative pain after endodontic treatment: randomized, controlled, clinical study | SpringerLink

It may be concluded that the use of photobiomodulation therapy was effective in reducing pain within the first 24 h when compared with the administration of Ibuprofen 600 mg.
#sunlight #pain - link.springer.com

Vitamin D deficiency is associated with poor muscle function in adults aged 60+ -- ScienceDaily

The prevalence of muscle weakness was twice as high among older adults with vitamin D deficiency (40.4%) compared with vitamin D adequacy (21.6%). Similarly, impaired 'muscle performance' was 3 times higher in older adults with vitamin D deficiency (25.2%) compared with vitamin D adequacy (7.9%). Based on more complex statistical analysis, the study showed that vitamin D deficiency significantly increased the likelihood of impaired muscle strength and performance. The study confirmed the associated benefits of physical activity. Older adults partaking in regular moderate physical activity had significantly lower likelihood of poor muscle strength and physical performance.
#aging #sunlight #muscles #vitamin-d - sciencedaily.com

Light works, Prozac ties placebo

A total of 122 patients were randomized (light monotherapy, 32; fluoxetine monotherapy, 31; combination therapy, 29; placebo, 30). The mean (SD) changes in MADRS score for the light, fluoxetine, combination, and placebo groups were 13.4 (7.5), 8.8 (9.9), 16.9 (9.2), and 6.5 (9.6), respectively. The combination (effect size [d] = 1.11; 95% CI, 0.54 to 1.64) and light monotherapy (d = 0.80; 95% CI, 0.28 to 1.31) were significantly superior to placebo in the MADRS change score, but fluoxetine monotherapy (d = 0.24; 95% CI, −0.27 to 0.74) was not superior to placebo.
#medicalindustrialcomplex #depression #sunlight #placebo #antidepressants #prozac - jamanetwork.com

Teens sleep 43 more minutes per night after combo of two treatments -- ScienceDaily

The treatment had two components: brief, early morning flashes of bright, broad-spectrum white light to reset the teens' circadian clocks, and cognitive behavioral therapy that motivated them to try earlier bedtimes. The findings will be published online Sept. 25 in JAMA Network Open. "Using a passive light therapy during sleep, we can help teens get an extra 43 minutes of sleep every single night," said senior author Jamie Zeitzer, PhD, associate professor of psychiatry and behavioral sciences. The light was delivered by a device in the teens' bedrooms that was programmed to deliver 3-millisecond flashes of light every 20 seconds during the last few hours of sleep. The brief flashes of light did not wake the teens. Zeitzer's previous research on jet lag had shown that exposure to short flashes of light can trick the brain into adjusting to a new time zone, even during sleep.
#paleotherapy #sleep #sunlight #teens - sciencedaily.com

The Week That Wasn't: Kimchi, Light Therapy, FDA Bleach Warning

After conducting mouse experiments, the researchers recruited healthy human volunteers, exposed them to intense light for 30 minutes, and analyzed protein levels in their blood to confirm that the biological changes from intense light that they observed in mice also occurred in people. The researchers posit that intense light therapy might be helpful for treating cardiovascular disease.
#paleotherapy #sunlight #heart - medscape.com

Light therapy could replace opioids as main treatment for cancer treatment side effect -- ScienceDaily

Light therapies have existed for decades, but improvements in the technology have made the treatment more affordable for wider use. At a high power, light, often in the form of a laser, is used in medicine to cut or destroy tissue. But at a low power, it has the ability to relieve pain or inflammation and promote healing. The treatment is rising in use across Europe, Brazil, India, Canada and several other nations. The findings provide an upgrade to previous guidelines published in 2013, which noted the effectiveness of light therapy and recommended, based on relatively limited evidence at that time, the intervention as an optional therapy in specific cancer patient populations and settings.
#sunlight #UV - sciencedaily.com

Insulin under the influence of light -- ScienceDaily

To better assess the effect of light on tissue sensitivity to insulin, researchers measured insulin-induced glucose absorption. It turns out that a small disturbance in photic inputs (e.g. an hour of light exposure in the middle of the dark cycle, or light removal for 2 days) is enough to cause a negative effect. Indeed, increased or decreased light exposure can profoundly influence the sensitivity of tissues to insulin and the alteration, however minimal, of this mechanism is sufficient to significantly disrupt metabolic homeostasis. This would explain why people exposed to light at the wrong time -- workers in shift patterns, for example -- are more likely to develop metabolic diseases (e.g. diabetes).
#circadian #diabetes #sunlight #insulin - sciencedaily.com

Dead zones in circadian clocks -- ScienceDaily

One of the important properties of circadian clocks is the response to light signals, which enables organisms to become entrained to the 24-hour light-dark cycle on Earth. It has been shown that circadian clocks respond to light signals during the night, whereas they do not respond to such signals during the daytime. This holds true even when an organism is kept in complete darkness; a short light pulse does not change the time of the circadian clock when body time of the individual is at daytime. The time period in which the circadian clock is insensitive to light signals is referred to as the "dead zone." Previous studies have indicated that the presence of a dead zone improves the robustness of the clock. However, the mechanism underlying its generation is unclear.
#synchronize #circadian #sunlight #bluelight - sciencedaily.com

Study links fluorescent lighting to inflammation and immune response - Neuroscience News

“In this report, we show genome-wide changes of gene expression patterns in skin, brain and liver for two commonly utilized fish experimental models (zebrafish and Japanese rice fish, also known as medaka), and a mammalian (mice), following exposure to 4,100 K ‘cool-white’ fluorescent light,” Walter said. “In spite of the extreme divergence of these animals (i.e., estimated divergence of mice and fish about 450 million years), and drastically different lifestyles (i.e., diurnal fish and nocturnal mice), the same highly conserved primary genetic response that involves activation of inflammation and immune pathways as part of an overall acute phase response was observed in the skin, brain and liver of all three animals. Follow-up studies to further define this response in mice are underway.”
#circadian #sunlight #inflamation #immune-system #UV - neurosciencenews.com

Octopuses can ‘see’ with their skin | Science News

So far, though, there’s no evidence in squids and cuttlefishes that light striking skin is enough to make chromatophores blush. Cronin isn’t completely ruling out the idea yet and speculates about more subtle roles. “Maybe they don’t respond directly, but they may alter a signal sent from the central nervous system,” he says. Research on light detection beyond eyes and brains “has been neglected for some time,” says developmental biologist Florian Raible of the University of Vienna. Yet non-eye light sensing structures or compounds show up in the tube feet of sea urchins and the body walls of fruit fly larvae. And in Raible’s lab, a polychaete worm flees light — even after beheading.
#sunlight #vision #UV - sciencenews.org

How to increase serotonin in the human brain without drugs

Relatively few generations ago, most of the world population was involved in agriculture and was outdoors for much of the day. This would have resulted in high levels of bright light exposure even in winter. Even on a cloudy day, the light outside can be greater than 1000 lux, a level never normally achieved indoors. In a recent study carried out at around latitude 45° N, daily exposure to light greater than 1000 lux averaged about 30 minutes in winter and only about 90 minutes in summer50 among people working at least 30 hours weekly; weekends were included. In this group, summer bright light exposure was probably considerably less than the winter exposure of our agricultural ancestors. We may be living in a bright light–deprived society. A large literature that is beyond the scope of this editorial exists on the beneficial effect of bright light exposure in healthy individuals. Lamps designed for the treatment of seasonal affective disorder, which provide more lux than is ever achieved by normal indoor lighting, are readily available, although incorporating their use into a daily routine may be a challenge for some. However, other strategies, both personal and institutional, exist. “Light cafes” pioneered in Scandinavia have come to the United Kingdom,51 and an Austrian village that receives no sunshine in the winter because of its surrounding mountains is building a series of giant mirrors to reflect sunlight into the valley.52 Better use of daylight in buildings is an issue that architects are increasingly aware of. Working indoors does not have to be associated with suboptimal exposure to bright light. A third strategy that may raise brain serotonin is exercise. A comprehensive review of the relation between exercise and mood concluded that antidepressant and anxiolytic effects have been clearly demonstrated.53 In the United Kingdom the National Institute for Health and Clinical Excellence, which works on behalf of the National Health Service and makes recommendations on treatments according to the best available evidence, has published a guide on the treatment of depression.54 The guide recommends treating mild clinical depression with various strategies, including exercise rather than antidepressants, because the risk–benefit ratio is poor for antidepressant use in patients with mild depression. Exercise improves mood in subclinical populations as well as in patients. The most consistent effect is seen when regular exercisers undertake aerobic exercise at a level with which they are familiar.53 However, some skepticism remains about the antidepressant effect of exercise, and the National Institute of Mental Health in the United States is currently funding a clinical trial of the antidepressant effect of exercise that is designed to overcome sources of potential bias and threats to internal and external validity that have limited previous research.55 Several lines of research suggest that exercise increases brain serotonin function in the human brain. Post and colleagues56 measured biogenic amine metabolites in cerebrospinal fluid (CSF) of patients with depression before and after they increased their physical activity to simulate mania. Physical activity increased 5-HIAA, but it is not clear that this was due to increased serotonin turnover or to mixing of CSF from higher regions, which contain higher levels of 5-HIAA, with lumbar CSF (or to a combination of both mechanisms). Nonetheless, this finding stimulated many animal studies on the effects of exercise. For example, Chaouloff and colleagues57 showed that exercise increased tryptophan and 5-HIAA in rat ventricles. More recent studies using intracerebral dialysis have shown that exercise increases extracellular serotonin and 5-HIAA in various brain areas, including the hippocampus and cortex (for example, see58–60). Two different mechanisms may be involved in this effect. As reviewed by Jacobs and Fornal,61 motor activity increases the firing rates of serotonin neurons, and this results in increased release and synthesis of serotonin.62 In addition, there is an increase in the brain of the serotonin precursor tryptophan that persists after exercise.63 The largest body of work in humans looking at the effect of exercise on tryptophan availability to the brain is concerned with the hypothesis that fatigue during exercise is associated with elevated brain tryptophan and serotonin synthesis. A large body of evidence supports the idea that exercise, including exercise to fatigue, is associated with an increase in plasma tryptophan and a decrease in the plasma level of the branched chain amino acids (BCAAs) leucine, isoleucine and valine (see64,65 for reviews). The BCAAs inhibit tryptophan transport into the brain.66 Because of the increase in plasma tryptophan and decrease in BCAA, there is a substantial increase in tryptophan availability to the brain. Tryptophan is an effective mild hypnotic,67 a fact that stimulated the hypothesis that it may be involved in fatigue. A full discussion of this topic is not within the scope of this editorial; however, it is notable that several clinical trials of BCAA investigated whether it was possible to counter fatigue by lowering brain tryptophan, with results that provided little support for the hypothesis. Further, exercise results in an increase in the plasma ratio of tryptophan to the BCAAs before the onset of fatigue.64,65 The conclusion of these studies is that, in humans, a rise in precursor availability should increase serotonin synthesis during and after exercise and that this is not related to fatigue, although it may be related to improved mood. Whether motor activity increases the firing rate of serotonin neurons in humans, as in animals, is not known. However, it is clear that aerobic exercise can improve mood.
#exercise #sunlight #serotonin - ncbi.nlm.nih.gov

Association of Testosterone Treatment With Alleviation of Depressive Symptoms in Men: A Systematic Review and Meta-analysis | Depressive Disorders | JAMA Psychiatry | JAMA Network

Random-effects meta-analysis of 27 RCTs including 1890 men suggested that testosterone treatment is associated with a significant reduction in depressive symptoms compared with placebo (Hedges g, 0.21; 95% CI, 0.10-0.32), showing an efficacy of odds ratio (OR), 2.30 (95% CI, 1.30-4.06). There was no significant difference between acceptability of testosterone treatment and placebo (OR, 0.79; 95% CI, 0.61-1.01). Meta-regression models suggested significant interactions for testosterone treatment with dosage and symptom variability at baseline. In the most conservative bias scenario, testosterone treatment remained significant whenever dosages greater than 0.5 g/wk were administered and symptom variability was kept low.
#depression #sunlight #testosterone - jamanetwork.com

Mouse and human skin cells produce melanin on a 48-hour cycle -- ScienceDaily

. They observed that a 48-hour cycle of exposure resulted in the darkest coloration of the cells while minimizing the effects of stress, even when they controlled for total dosage of exposure. "The results were so surprising," says Levy. "We expected daily synchronization of the cell's protective cycles." Levy and her colleagues, including co-senior author and systems biologist Shai Shen-Orr and his PhD student Avelet Alpert of the Technion -- Israel Institute of Technology, observed that MITF (microphthalmia-associated transcription factor) seemed to play a role in synchronizing the protective cycles. MITF was previously shown to control production of melanin and its spread to surrounding skin cells. They found that upon one ultraviolet exposure, MITF expression fluctuates every 48 hours. Another exposure 24 hours later seemed to disrupt this expression pattern.
#circadian #sunlight #UV - sciencedaily.com

CivicScience | Getting More Sunlight is Closely Tied to Happiness, Lots of Other Good Things

People who believe they receive more sunlight than their peers are twice as likely than average and nearly 3.5 times as likely as those who get less sunlight to consider themselves “Very Happy.”
#sunlight - civicscience.com

Starving for light – henry copeland – Medium

Without seeing a 30 minute dose of bright light each morning, your circadian clock can derail, affecting everything from gene expression to hormonal ebbs and flows to testosterone levels to virus virility to brain waves to immunity to REM patterns to fertility to heart rates to hunger to cancer.
#running #sunlight - medium.com

Color-Changing LEDs Could Reset the Circadian Rhythm - The Atlantic

Hints of positive impacts have emerged in Texas, too, where tunable LED systems have been installed in some elementary and middle-school classrooms in Carrollton, a northern suburb of Dallas. A September DOE report on the Carrollton systems suggested that the tunable LED system had improved the overall learning environment—though the DOE noted that empirically measuring the effects of the circadian lights was beyond the scope of the project. Back in Washington, entire schools—including two Renton high schools and a brand new middle school—now have circadian lighting, and initial data out of Lindbergh High School seemed to echo the findings in Texas: The school reported a double-digit rise in SAT test scores following installation of the tunable LEDs.
#paleotherapy #circadian #sunlight #chronotherapy #tunable-leds - theatlantic.com

Color-Changing LEDs Could Reset the Circadian Rhythm - The Atlantic

In much the same way as the ear allows us to both hear and stay balanced, the eye’s rods and cones supply us with vision while these novel intrinsic photosensitive retinal ganglion cells, or ipRGCs, perform a separate function: They sense the quality and quantity of light, with input from the rods and cones, and send that information to a master circadian clock in the brain. That clock then conducts a symphony of cellular timepieces throughout the body, ensuring they all “rise and fall with appropriate relationships to the others,” explains Berson.
#paleotherapy #circadian #sunlight #bluelight - theatlantic.com