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The Culprit of Bad Sleep

About a decade ago Los Angeles–based software developer Lorna Herf decided to try her hand at oil painting. She and her husband, Michael, also a computer programmer, eventually installed bright fluorescent lights in their apartment’s loft so that Lorna could paint at night and still have an accurate sense of what colors on the canvas would look like during the day. Late one evening Lorna descended to the living room, where computer screens were aglow. Now that she had become more attuned to differences in lighting, she noticed just how much the bright light from the computer screens clashed with the soft warmth of the incandescent bulbs that surrounded them. She remembers thinking the electronic screens were “like little windows of artificial daylight,” spoiling the otherwise gentle ambience of the room.

The tech-savvy couple engineered a crafty solution to minimize the discrepancy. They wrote some code to change the number and wavelength of the photons emitted by their computer screens as a day progressed. The Herfs’ goal was to mimic natural shifts in ambient light as closely as possible, transitioning from the bright, bluish-white light characteristic of morning and afternoon sunshine to a dim, orange glow in the evening.

At first, they simply intended to harmonize the lighting scheme in their home. But they soon began to suspect that their new app, dubbed f.lux, might offer some health benefits as well. “After we’d been using it for a while, we started to notice it seemed easier to wind down at night,” Lorna recalls, making it easier to fall asleep when they turned off their electronic devices. They are not the only ones who have appreciated the calming effect. Since the Herfs released the program for free in 2009, f.lux has been downloaded more than 20 million times.

By following their aesthetic taste, the Herfs had stumbled on a curious twist in the way the body controls how we sleep. Researchers have known for several decades that strong light of any kind can suppress melatonin, the hormone the brain produces at night to induce sleepiness. But more recent studies show that blue light suppresses melatonin more effectively than any other visible wavelength, potentially leaving people more alert when they would otherwise start feeling drowsy.

As it happens, smartphones, laptops and all kinds of electronic screens have become brighter and bluer over the past couple of decades because of the addition of powerful blue LEDs. During the day, when blue light is already naturally plentiful, a little extra exposure from electronic screens should not make much of a difference to anyone’s physiology. The problem is that people are increasingly staring into bright screens long into the night.

Nearly everyone in a survey conducted by the National Sleep Foundation in 2011, for example, used a television, computer, cell phone or similar device within an hour of going to bed at least a few nights a week. In 2014 the same organization determined that 89 percent of adults and 75 percent of children in the U.S. have at least one electronic device in their bedroom, with a significant number of them sending or answering texts after they had initially fallen asleep. Motivated by such research, engineers and computer programmers are trying out various solutions to keep an already sleep-deprived population from losing more zzz’s because of their electronic devices. The solutions range from tinted eyeglasses to naturalistic lighting systems for the home and office.

“If people can figure out ways to simulate changes in sunlight across the day, that would be perfect,” says Christian Cajochen, head of the Center for Chronobiology at the University of Basel in Switzerland. “The ideal would be to have the same light throughout your home as outside of it.” It remains to be seen how effective these remedies are, however, especially when compared with simply shutting the devices off.


The light emanating from electronic devices was not always such a hindrance to restful sleep. The current state of affairs can be traced to the 1992 invention in Japan of the high-brightness blue LED. By combining the new blue LEDs with older green and red ones or coating blue LEDs with chemicals that reemit other wavelengths, technology manufacturers could generate full-spectrum white LED light for the first time. Because LEDs are much more energy-efficient than their fluorescent predecessors, they soon became ubiquitous in TVs, computer screens, tablets and certain e-readers, infusing homes and offices with much brighter blue light than ever before.

Researchers did not begin amassing concrete evidence that blue LEDs can disrupt sleep until about 15 years ago, but they have had a good idea of the probable mechanism for quite some time. Scientists had discovered back in the 1970s that a tiny brain region dubbed the suprachiasmatic nucleus helps to control the body’s sleep cycles, alertness, temperature and other daily fluctuations. Studies showed that the suprachiasmatic nucleus prompts the brain’s pineal gland to produce melatonin every evening.

Earlier this century biologists uncovered exactly how this signaling process happens. As it turns out, the missing link was a previously unknown type of light-sensitive cell in the human eye, distinct from the familiar rods and cones that are responsible, respectively, for night and color vision. This third so-called photoreceptor tracks the amount of blue light in the environment and reports back to the suprachiasmatic nucleus. Thus, when there is a lot of blue light (as when the sun is overhead), this particular photoreceptor prompts the suprachiasmatic nucleus to tell the pineal gland not to make much melatonin, and so we stay awake. When the sun begins to set, however, the amount of blue light diminishes, triggering a surge in melatonin levels, prompting us to fall asleep.

Among the studies offering evidence that screens with blue LEDs might confuse the brain at night is a 2011 investigation by the University of Basel’s Cajochen and his colleagues. In that work, volunteers exposed to an LED-backlit computer for five hours in the evening produced less melatonin, felt less tired, and performed better on tests of attention than those in front of a fluorescent-lit screen of the same size and brightness. Similarly, for subjects in a 2013 study led by Mariana Figueiro of the Rensselaer Polytechnic Institute, interacting with an iPad for just two hours in the evening was enough to prevent the typical nighttime rise of melatonin. And in a two-week trial at Brigham and Women’s Hospital in Boston, published in 2014, volunteers who read on an iPad for four hours before bed reported feeling less sleepy, took an average of 10 minutes longer to fall asleep and slept less deeply compared with those who read paper books at night. Cajochen and others have also shown that these effects are especially pronounced in teens and adolescents, for reasons that remain unclear.


Given the accumulating evidence that artificial screens in general and blue lights in particular spoil sleep, scientists have begun investigating various remedies. Several studies have shown that wearing orange-tinted plastic goggles, which filter out the blue light emanating from electronic devices, helps to prevent melatonin suppression. Similar glasses are now commercially available for as little as $8 or as much as $100. A more expensive option is a so-called dynamic lighting system, which promises to re-create “the full range of natural daylight in an interior space” for hundreds to thousands of dollars depending on the size of one’s home or office.

The most affordable countermeasures are computer programs such as f.lux. This past March, Apple introduced a function called Night Shift for the iPhone and iPad, which mimics f.lux in shifting the screen’s emitted light “to the warm end of the spectrum” around sunset. So far no researchers have tested f.lux or Apple’s Night Shift in a controlled study, but Figueiro says she is planning to conduct such experiments, and Michael Herf says he is collaborating with university scientists to examine the effects of f.lux in everyday environments outside the laboratory. “F.lux in my view is still a hypothesis,” Herf adds. “We think it probably helps a lot of night owls, but we still need to support the anecdotes with data.”

Researchers emphasize, however, that eliminating blue light is not a fail-safe solution. Even dim, orange screens make it tantalizingly easy to stay awake and read, watch movies or play games at night, keeping your brain alert when it should be winding down. “It’s as if you’re completely in the dark, but you drink coffee,” Figueiro explains. “It’s still going to have an effect.”

Ultimately the surest solution is electronic abstinence: shutting off all screens and bright lights for at least a few hours before bedtime. The inescapable fact is that humans evolved to rise and sleep with the sun. “Before we had all this technology, before electricity and artificial lighting, we would be awake in daylight, have a little bit of fire in the evening, and then sleep,” says Debra Skene, a chronobiologist at the University of Surrey in England. Artificial light has been enormously beneficial over the centuries. But there are times, especially at the end of the day, when it can be too much of a good thing.

6 Basic Principles Of Using Food As Medicine

In 1973, when I was a researcher at the National Institute of Mental Health and beginning to become interested in alternative therapies, I met Shyam Singha, a London-based Indian osteopath, naturopath, herbalist, acupuncturist, homeopath, and meditation master. Shyam had gleaming yellow eyes and flowing black hair, and wore impeccably tailored Savile Row suits or floor-length, orange silk gowns.

Lecturing, he paced the front of the hall like a panther. A brilliant, challenging, occasionally terrifying trickster, he became my guide to the frontiers of healing. Together Shyam and I cooked meals that astonished my taste buds, raised my energy, and lifted my mood. The fast, “chaotic” breathing meditation he had learned in the Indian mountains pushed me through fear and anger.

Shortly after meeting Shyam, I was crippled by a back injury. The orthopedists were issuing dire warnings and getting me ready for a surgery I didn’t want.

Desperate, I called Shyam in London. “Eat three pineapples a day, and nothing else for a week,” he said.

I thought the phone had gone bad, and then suspected, not for the first time, that he was mad. He repeated it and explained, using principles of Chinese medicine, how the pineapple would “work on your lung” which was the “mother of the kidney,” and that the kidney was “connected” to the back. It made no sense to me then, but I knew that Shyam knew many things that I and the orthopods didn’t.

And I really didn’t want back surgery.

Amazingly, the pineapple fast worked. Later, Shyam suggested I eliminate gluten,dairy, sugar, red meat and processed food to relieve my occasional allergies, asthma, and eczema. That worked, too.

Ever since, I too have been committed to using food as medicine. Soon I was reading scientific studies that were validating the therapeutic power of traditional remedies and suggesting the need to eliminate or cut down on foods that had become staples of the standard American diet. I began to prescribe nutritional therapies for my medical and psychiatric patients.

By the early 1990s, I had decided it was time to teach what I was learning to my students at Georgetown Medical School. I asked Susan Lord, MD, my colleague atThe Center for Mind-Body Medicine, to join me. To honor Hippocrates, who coined the phrase, we called our course “Food As Medicine,” and it quickly became a hit with med students.

The students experimented with diets that eliminated sugar, gluten, dairy, food additives, red meat and caffeine. Many felt less anxious and more energetic; they slept and studied better and learned more easily. They shook their heads at how little attention their curriculum paid to nutrition.

A few years later, Susan and I made an expanded version of this course available nation-wide, to medical school faculty, physicians, other health professionals and anyone who was interested in improving her own nutrition.

Together with the dietician Kathie Swift, we created exactly the course we wish we’d had in school — one combining impeccable science and traditional wisdom, presented in the most interesting, practical user-friendly way. We called it “Food As Medicine” (FAM)

The course is comprehensive, but the basic principles are simple and straightforward:

1. Eat in harmony with your genetic programming — i.e,. the way our hunter-gatherer ancestors ate.

This doesn’t mean conforming to a strict Paleo diet, but rather following the guidelines it suggests. Consider a whole foods plant-based diet with as little processed food and added sugar as possible.

Ideally this means consuming far fewer grains (understanding that some people can’t tolerate wheat and other grains at all); little or no dairy (even if you don’t seem intolerant to it); cold water fish like salmon, sardines and mackerel as the preferred animal product; and far more intestine-activating fiber — we consume a paltry average of 15 grams a day; our Paleolithic ancestors took in 100 grams.

2. Use foods rather than supplements to treat and prevent chronic illness.

Whole foods contain a number of substances that work synergistically and may be far more effective than supplements that just deliver one of them.

Why take the powerful antioxidant lycopene in a pill when you can eat a tomato that contains both lycopene and a number of other antioxidants, along with vitamins, minerals and other nutrients that work together to prevent heart disease by decreasing cholesterol and lipid levels and stopping abnormal blood clotting?

3. Combine your nutritional plan with a program to reduce stress and raise awareness about how as well as what we eat.

Stress inhibits and interferes with every aspect of digestive functioning and with the efficient use of nutrients. Stressed-out people can’t make very good biological use of even the most healthy diets.

Learning to eat slowly and mindfully will increase your enjoyment of meals, reduce your consumption of food (most of us eat so fast we don’t have time to register signals from our stomach that we are full), and help you make food choices that are better for you.

4. Understand that we are all, as the pioneering biochemist Roger Williams pointed out 50 years ago, biochemically unique.

We may be the same age and ethnicity, have very similar health status, ethnicity, and income, but you may use 100 times as much B6 as I do, and I may require 100 times more Zinc.

Sometimes we may need a nutritionally oriented physician, dietician or nutritionist to do specific, sophisticated tests to determine our deficiencies and requirements. We can always learn a great deal about what’s good for us by experimenting with different diets and foods, and by paying close attention to the outcomes.

5. Find a health professional who will help you begin treatment of chronic conditions with nutrition and stress management (as well as exercise) rather than medication.

Except in life threatening situations, this is the sane, common sense way to go. The prescription antacids, Type 2 diabetes drugs, and antidepressants that tens of millions of Americans use to decrease acid reflux, lower blood sugar, and improve mood, only treat symptoms and do not address causes. And they have very significant and often dangerous side-effects. If they are only prescribed, as they should be, after a thorough trial of non-pharmacological treatment, they will rarely be necessary.

6. Don’t become a food fanatic.

Use these guidelines (and others that make sense to you), but don’t beat yourself up for deviating from them. Just notice the effect of a questionable choice, learn, and return to your program.

And don’t waste your time and energy judging others for what they eat! It will just make you cranky and self-righteous, stressful emotional states that will ruin your digestion. And it sure won’t do those other people any good.