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Sunlight May Be the Next Beet Juice | Outside Online

The study involved shining two different doses of ultraviolet light (specifically UVA light—wavelengths between 315 and 400 nanometers) on ten volunteers, then measuring its effects on a range of outcomes like blood pressure, resting metabolism, and nitrite and nitrate levels. It’s this last bit that caught my attention, because the rise of beet juice as an endurance-boosting supplement is due to its high levels of nitrate. The body converts that nitrate to nitrite and then to nitric oxide, which seems to make your muscles work more efficiently during endurance exercise. These studies have also found that boosting levels of nitric oxide has other health benefits, like acutely lowering blood pressure and regulating blood sugar. (In fact, one recent study found that using mouthwash twice a day or more, which wipes out the oral bacteria that convert nitrate to nitrite, was associated with a 50 percent increase in the risk of developing prediabetes or diabetes.)

Living in a sunnier climate as a child and young adult may reduce risk of MS: Getting more summer sun also associated with lower risk -- ScienceDaily

They found that women who lived in sunnier climates with the highest exposure to UV-B rays had 45 percent reduced risk of developing MS across all pre-MS onset age groups when compared to those living in areas with the lowest UV-B ray exposure. When looking at specific age groups, those who lived in areas with the highest levels of UV-B rays between ages 5 to 15 had a 51 percent reduced risk of MS compared to the lowest group. A total of 33 of 147 people with MS, or 22 percent, had high exposure at ages 5 to 15, while 61 people, or 41 percent, had low exposure. In addition, those who spent more time outdoors in the summer at ages 5 to 15 in locations where exposure to UV-B rays was the highest had a 55 percent reduced risk of developing the disease compared to those in the lowest-exposure group.

Our circadian clock sets the rhythm for our cells’ powerhouses -- ScienceDaily

Countless genetically controlled clocks tick inside different parts of our bodies, such as the liver, kidneys and heart. Among other things, they initiate many metabolic processes, ensuring that these occur at the optimal time of day. Mitochondria -- small organelles that exist in almost all our cells and supply them with energy -- play an important role in these cellular processes. Until now, it was unclear how exactly the 24-hour circadian rhythm regulated energy metabolism. Fission protein sets the rhythm In most cells, mitochondria connect in a constantly changing network that can adapt to various conditions. Mitochondria can thus fuse together and then divide again. Disruption of this fission-fusion dynamic can lead to health problems. Researchers have now investigated exactly how the mitochondrial network interacts with our internal biological clock by using a combination of in vitro models and clock-deficient mice or mice with impaired mitochondrial fission. Their results show that the mitochondrial fission-fusion cycle is controlled by the fission protein Drp1, which is in turn synchronized by an internal biological clock. This rhythm is integral to determining when and how much energy the mitochondria can supply. "The time of day determines the design of the mitochondrial network, and this, in turn, influences the cells' energy capacity," explains study leader Professor Anne Eckert from the University of Basel's Transfaculty Research Platform Molecular and Cognitive Neurosciences MCN.

Recap of sunlight with links

Although medical curiosity about the salubrious benefits of sunlight exposure can be traced to antiquity [1,2], contemporary clinical interest was ignited by the 20th-century discovery of a direct link between light exposure and circadian melatonin production [3,4]. An obvious initial candidate for bright light therapy (LT) was seasonal affective disorder [5] – a form of depressive illness typically triggered by light deprivation during the short, cold days of winter – and the intervention has proven to be efficacious across a large number of randomized controlled trials [6-8]. In fact, the efficacy of LT has now been supported across a range of other mood disorders, including non-seasonal depression [9,10,6], bipolar disorder [11,12], antepartum and postpartum depression [13,14], and premenstrual dysphoric disorder [15,16]. Light therapy (LT) has also been successfully applied to the treatment of sleep disorders [17-20], as well as circadian phase sleep disorders associated with jet lag [21,22] and shift work [23,24]. More recently, LT has shown promise as an intervention for obsessive-compulsive symptoms [25], behavioral disturbances and functioning in dementia and Alzheimer’s disease [26,27], primary and secondary features of Parkinson’s disease [28], attention deficit hyperactivity disorder [29], seasonal variations in eating disturbances associated with bulimia nervosa [30,31], and some symptoms of chronic anorexia [32].

Visualizing assemblies of the proteins that direct cyanobacterial circadian rhythms

KaiB, though, flips between two different shapes, and is only active when it's in an unstable shape—a situation that until now made crystallization impossible. "We mutated KaiB so that it stayed in its active shape, and when we added KaiA and KaiC they arranged themselves around it as they do at night," LiWang said. "We found the secret sauce that allows us to figure out how the springs and gears go together." They were amazed that they obtained crystals within a day of combining the proteins. They also solved an NMR structure of a complex between the active form of KaiB and the domain of a protein (CikA) that transmits signals to regulate gene expression in cyanobacteria. "It's really remarkable that the cyanobacterial clock is so dependent on this rare state of KaiB," Partch said. "The mechanistic information we're getting out of these structures is allowing us to piece together how the clock manages to keep 24-hour time. We're now looking for similar clues in other circadian timekeeping systems, including our own."

Clock protein controls daily cycle of gene expression by regulating chromosome loops: New understanding of Rev-erb's role has implications for metabolic disorders, cardiovascular disease, and cancer -- ScienceDaily

Human physiology works on a 24-hour cycle of gene expression (when the chromosome coding region is translated by RNA and then transcribed to make protein) and is controlled by the body's molecular clock. Core clock proteins activate or repress protein complexes that physically loop one part of a chromosome to become adjacent to a distant part of the same chromosome. The Penn team showed that daily oscillations of Rev-erb control gene expression in the mouse liver via interactions between on-and-off regions on the same chromosome. Previous work from the team demonstrated that by 5 p.m., Rev-erb increases to its highest concentration in mouse liver, where it turns off certain genes and therefore protein transcription. But as the day turns to night, its concentration steadily decreases and nearly vanishes from the liver by 5 a.m.

Does dim light make us dumber? -- ScienceDaily

Spending too much time in dimly lit rooms and offices may actually change the brain's structure and hurt one's ability to remember and learn, indicates groundbreaking research by Michigan State University neuroscientists. The researchers studied the brains of Nile grass rats (which, like humans, are diurnal and sleep at night) after exposing them to dim and bright light for four weeks. The rodents exposed to dim light lost about 30 percent of capacity in the hippocampus, a critical brain region for learning and memory, and performed poorly on a spatial task they had trained on previously. The rats exposed to bright light, on the other hand, showed significant improvement on the spatial task. Further, when the rodents that had been exposed to dim light were then exposed to bright light for four weeks (after a month-long break), their brain capacity -- and performance on the task -- recovered fully.

UV Sense

I’ll make a bold claim: one hundred years from now, the UV Sense and its peers may be celebrated for being as important to health in the 21st century as insulin and penicillin were in the 20th century. UV Sense is one of a whole new class of consumer-targetted devices/services like FitBit, Spire, 23andme, home-built EEGs, and various microbiome sensors and assays that are as powerful as could be found a decade ago in cutting-edge research labs. Combined with crowdsourcing and cheap big data tools, these people-empowering devices will help individuals pursue hypotheses that no profit-driven business cares (or dares) to examine.

Amber-tinted glasses may provide relief for insomnia -- ScienceDaily

To test their theory, the researchers recruited 14 individuals with an insomnia diagnosis to take part in a small study. For seven consecutive nights, participants wore wrap-around frames with amber-tinted lenses that blocked blue light or with clear placebo lenses for two hours before bedtime. Four weeks later, participants repeated the protocol with the other set of glasses. The researchers found that participants got around 30 minutes extra sleep when they wore the amber lenses compared to the clear lenses. In self-reported sleep surveys, participants also reported greater duration, quality, and soundness of sleep, and an overall reduction in insomnia severity.

Time matters: Does our biological clock keep cancer at bay? -- ScienceDaily

Relógio, whose surname in Portuguese means "clock," says: "Based on our results, it seems to us that the clock is likely to act as a tumour suppressor, and that it is of advantage for cancer cells to circumvent circadian control. One cannot stop wondering whether disrupted circadian timing should be included as a next potential hallmark of cancer."

Outdoor light at night linked with increased breast cancer risk in women | News | Harvard T.H. Chan School of Public Health

Women exposed to the highest levels of outdoor light at night—those in the top fifth—had an estimated 14% increased risk of breast cancer during the study period, as compared with women in the bottom fifth of exposure, the researchers found. As levels of outdoor light at night increased, so did breast cancer rates.

New Yorker Menuchin on the eclipse: meh.

"You know, people in Kentucky took this stuff very serious," he told the conference. "Being a New Yorker and (living for a time in) California, I was like, the eclipse? Really? I don't have any interest in watching the eclipse."

Comparisons of three practical field devices used to measure personal light exposures and activity levelsLighting Research & Technology - MG Figueiro, R Hamner, A Bierman, MS Rea, 2013

This paper documents the spectral and spatial performance characteristics of two new versions of the Daysimeter, devices developed and calibrated by the Lighting Research Center to measure and record personal circadian light exposure and activity levels, and compares them to those of the Actiwatch Spectrum. Photometric errors from the Daysimeters and the Actiwatch Spectrum were also determined for various types of light sources. The Daysimeters had better photometric performance than the Actiwatch Spectrum. To assess differences associated with measuring light and activity levels at different locations on the body, older adults wore four Daysimeters and an Actiwatch Spectrum for seven consecutive days. Wearing the Daysimeter or Actiwatch Spectrum on the wrist compromises accurate light measurements relative to locating a calibrated photosensor at the plane of the cornea.

Effects of exercise with or without light exposure on sleep quality and hormone reponses

Cycling adenosine monophosphate (cAMP) gets released by the stimulus of adrenocortical hormones due to intake of coffee, tea, chocolate, or stress. Excessive cAMP release accelerates energy release to reach excitement condition that leads us to be nervous and unsettled. However, sunlight exposure decreases cAMP, leading to peaceful and settled conditions [53].

10x risk of death from non-skin cancer due to low sun exposure

Many studies have shown that cancer-related death rates decline as one moves toward the lower latitudes (between 37°N and 37°S), and that the levels of ambient UVR in different municipalities correlate inversely with cancer death rates there. “As you head from north to south, you may find perhaps two or three extra deaths [per hundred thousand people] from skin cancer,” says Vieth. “At the same time, though, you’ll find thirty or forty fewer deaths for the other major cancers. So when you estimate the number of deaths likely to be attributable to UV light or vitamin D, it does is not appear to be the best policy to advise people to simply keep out of the sun just to prevent skin cancer.”

Lower risk of high blood pressure with sunlight

exposed a group of hypertensive adults to a tanning bed that emitted full-spectrum UVR similar to summer sunlight. Another group of hypertensive adults was exposed to a tanning bed that emitted UVA-only radiation similar to winter sunlight. After three months, those who used the full-spectrum tanning bed had an average 180% increase in their 25(OH)D levels and an average 6 mm Hg decrease in their systolic and diastolic blood pressures, bringing them into the normal range. In constrast, the group that used the UVA-only tanning bed showed no change in either 25(OH)D or blood pressure.

Low vitamin D = 4-5X increase in risk of type 1 diabetes

A Swedish epidemiologic study published in the December 2006 issue of Diabetologia found that sufficient vitamin D status in early life was associated with a lower risk of developing type 1 diabetes. Nonobese mice of a strain predisposed to develop type 1 diabetes showed an 80% reduced risk of developing the disease when they received a daily dietary dose of 1,25(OH)D, according to research published in the June 1994 issue of the same journal. And a Finnish study published 3 November 2001 in The Lancet showed that children who received 2,000 IU vitamin D per day from 1 year of age on had an 80% decreased risk of developing type 1 diabetes later in life, whereas children who were vitamin D deficient had a fourfold increased risk. Researchers are now seeking to understand how much UVR/vitamin D is needed to lower the risk of diabetes and whether this is a factor only in high-risk groups.

North of 37 degrees double MS risk

living at a latitude above 37° increased the risk of developing MS throughout life by greater than 100%.

Melanoma away from sun exposure

Moreover, although excessive sun exposure is an established risk factor for cutaneous malignant melanoma, continued high sun exposure was linked with increased survival rates in patients with early-stage melanoma in a study reported by Marianne Berwick, an epidemiology professor at the University of New Mexico, in the February 2005 Journal of the National Cancer Institute. Holick also points out that most melanomas occur on the least sun-exposed areas of the body, and occupational exposure to sunlight actually reduced melanoma risk in a study reported in the June 2003 Journal of Investigative Dermatology.

Lower rates of some cancers with vitamin D

Whereas skin cancer is associated with too much UVR exposure, other cancers could result from too little. Living at higher latitudes increases the risk of dying from Hodgkin lymphoma, as well as breast, ovarian, colon, pancreatic, prostate, and other cancers, as compared with living at lower latitudes. A randomized clinical trial by Joan Lappe, a medical professor at Creighton University, and colleagues, published in the June 2007 issue of the American Journal of Clinical Nutrition, confirmed that taking 2–4 times the daily dietary reference intake of 200–600 IU vitamin D3 and calcium resulted in a 50–77% reduction in expected incidence rates of all cancers combined over a four-year period in post-menopausal women living in Nebraska.

Sun reduces TB

a meta-analysis published in the February 2008 International Journal of Epidemiology found that high vitamin D levels reduce the risk of active TB (i.e., TB showing clinical symptoms) by 32%.

White skin an evolutionary adaption for low sunlight in north latitudes?

In the July 2000 issue of the Journal of Human Evolution, California Academy of Sciences anthropologists Nina Jablonski and George Chaplin wrote that because dark skin requires about five to six times more solar exposure than pale skin for equivalent vitamin D photosynthesis, and because the intensity of UVB radiation declines with increasing latitude, one could surmise that skin lightening was an evolutionary adaptation that allowed for optimal survival in low-UVR climes, assuming a traditional diet and outdoor lifestyle.

Smarter in the sun?

Besides suppressing melatonin and warding off any residual sleepiness, recent studies suggest that bright light acts as a stimulant to the brain. Gilles Vandewalle and colleagues at the University of Liège in Belgium asked volunteers to perform various tasks in a brain scanner while exposing them to pulses of bright white light or no light. After exposure to white light, the brain was in a more active state in those areas that were involved in the task. Although they didn’t measure the volunteers’ test performances directly, if you are able to recruit a greater brain response, then your performance is likely to be better: you will be faster or more accurate, Vandewalle says.

Is the dark really making me sad? | Ars Technica

Since October 2015, Anna’s classroom has been fitted with ceiling lights that change in colour and intensity to simulate being outside on a bright day in springtime. Developed by a company called BrainLit, the ultimate goal is to create a system that is tailored to the individual, monitoring the type of light they’ve been exposed to through the course of a day and then adjusting the lights to optimise their health and productivity.

Is the dark really making me sad? | Ars Technica

the leading theory is the ‘phase-shift hypothesis’: the idea that shortened days cause the timing of our circadian rhythms to fall out of sync with the actual time of day, because of a delay in the release of melatonin. Levels of this hormone usually rise at night in response to darkness, helping us to feel sleepy, and are suppressed by the bright light of morning. “If someone’s biological clock is running slow and that melatonin rhythm hasn’t fallen, then their clock is telling them to keep on sleeping even though their alarm may be going off and life is demanding that they wake up,” says Kelly Rohan, a professor of psychology at the University of Vermont. Precisely why this should trigger feelings of depression is still unclear. One idea is that this tiredness could then have unhealthy knock-on effects. If you’re having negative thoughts about how tired you are, this could trigger a sad mood, loss of interest in food, and other symptoms that could cascade on top of that. However, recent insights into how birds and small mammals respond to changes in day length have prompted an alternative explanation. According to Daniel Kripke, an emeritus professor of psychiatry at the University of California, San Diego, when melatonin strikes a region of the brain called the hypothalamus, this alters the synthesis of another hormone—active thyroid hormone—that regulates all sorts of behaviours and bodily processes. When dawn comes later in the winter, the end of melatonin secretion drifts later, says Kripke. From animal studies, it appears that high melatonin levels just after the time an animal wakes up strongly suppress the making of active thyroid hormone—and lowering thyroid levels in the brain can cause changes in mood, appetite, and energy. For instance, thyroid hormone is known to influence serotonin, a neurotransmitter that regulates mood. Several studies have shown that levels of brain serotonin in humans are at their lowest in the winter and highest in the summer. In 2016, scientists in Canada discovered that people with severe SAD show greater seasonal changes in a protein that terminates the action of serotonin than others with no or less severe symptoms, suggesting that the condition and the neurotransmitter are linked.

Is the dark really making me sad? | Ars Technica

Seasonality is reported by approximately 10 to 20 percent of people with depression and 15 to 22 percent of those with bipolar disorder. “People often don’t realise that there is a continuum between the winter blues—which is a milder form of feeling down, [sleepier and less energetic]—and when this is combined with a major depression,” says Anna Wirz-Justice, an emeritus professor of psychiatric neurobiology at the Centre for Chronobiology in Basel, Switzerland. Even healthy people who have no seasonal problems seem to experience this low-amplitude change over the year, with worse mood and energy during autumn and winter and an improvement in spring and summer, she says.