5 Health Hazards of Junk Light?

By Dr. Panchajanya "Panch" Paul, MD

We are all aware of junk food (like coke, burger, fries, nuggets) and their dangers. Junk food gives us excess calories without giving the nutrition. But few are aware of the dangers of Junk light. Junk light are the artificial lights coming from fluorescent, LED, and the screens of computer, laptop, and smart phones. Junk light emits excess blue light, and no infrared and ultraviolet rays. Junk food gives us malnourishment, similarly, junk light gives us malillumination, a term coined by Dr. John Ott. In the past, most of our light came either from the sun, or through fire generated by burning wood, coal, fat and oil. Then in the beginning of 19th century, Edison invented the incandescent light. Fire and incandescent light are closer to natural light as they give more natural light rays. However, the old lights, consumed too much energy as they gave out the infra-red light along with red, orange, and yellow lights. In recent years there is a big shift to replace all old lights with the new energy efficient Compact fluorescents (CFLs) and LEDs. These are energy efficient because they only emit waves which we can see and omit the infra-red and the ultraviolet.

Natural light coming from the sun is full spectrum light which contains the seven wavelengths of the visible spectrum along with other electromagnetic waves like infra-red, and ultra violet which our eyes cannot see, but our body feels. Junk light, on the contrary are limited to a narrow spectrum, and are blue light dominant. Among the visual spectrum, blue lights have the shortest wavelength, and the highest frequency. Blue has the highest energy and maximum penetrating power. Artificial lights have 5 times more blue waves than the sunlight. The high blue comes at the expense of the infra-red light, and the ultra violet light. Although our eyes cannot use them for vision, our body needs them. The infra-red light is felt by the body as heat and is required for mitochondrial function and are great for detoxification. The ultraviolet rays are used by the body to make vitamin D and endorphins. In addition, light regulates the release of hormones like testosterone, growth hormone, cortisol and neurotransmitters like serotonin, dopamine and melatonin. All these determines our mood, energy, motivation, health, and happiness.

Here are the 5 common problems with junk light:


1. Eye Strain & Exhaustion: Artificial bright light causes pupillary constriction. Then reading on the computer, forces our eyes to focus closer. Prolonged use causes eye strain and increases risk of near-sightedness or myopia. Also, the brain spends an enormous amount of energy to process the visual stimuli. Of all lights, blue requires the maximum energy, and can overhaul the visual cortex, causing exhaustion. I first became aware of this when my medical practice switched from paper charts and to electronic health records. I saw the same number pf patients, did the same documentation, and provided same clinical care. But at the end of the work day, I felt more tired. Later, I realized, staring at the computer screen all day, under the fluorescent light was sapping all my energy.

2. Sleep problems & Cancer: We are meant to be exposed to sunlight during the day and dark at night. Any light at night will disrupt the sleep wake cycle, also called the circadian rhythm. Blue light inhibits the melatonin production 5 times more than the red light. Low melatonin level at night will disrupt sleep. Have you noticed, how you struggle to sleep after watching a late-night movie, playing video games, or working on your smart screens. The blue lights reaching our retina confuses our body into thinking that the time is day, a time for wakefulness. The hormone melatonin signaling night time and sleep time is suppressed. Melatonin is a powerful antioxidant, and protects against cancer, and infection. Working under artificial lights at night raises the risk of infection and cancer. Multiple studies have found that nurses working at night under artificial lights have an increased risk of breast cancer than those working during the day.

3. Macular degeneration: Our eyes have evolved to primarily deal with the sunlight which is mostly red, orange and yellow. Blue light has short wavelength, but high frequency and energy. They readily penetrate the cornea, the lens, and reach the retina. Excess exposure to blue light can damage the light sensitive cells in the retina. This has been linked to macular degeneration- which is a common cause of age related visual loss and blindness. The damage is gradual and symptoms develop over the years. All the young people who are spending excess time on their smart phones, and video games - are at a high risk for blindness from macular degeneration later on.

4. Hormonal Imbalance & metabolic problems: Blue light suppress melatonin production and stimulates cortisol production. Under natural light body secrete the cortisol during the day, and melatonin during the night. Artificial light at night alters these cycle, and cortisol levels do not drop at night, and stay elevated. These stress hormones increase blood pressure, blood sugar, and blood cholesterol. Blue light can increase hunger, carbohydrate craving, and obesity. Thus, in long term there is more risk of diabetes, heart disease, and stroke.

5. Mental problems: Long exposure to artificial lights are bad for mental wellbeing. Blue light is addictive. I am seeing lot of young people who have become addicted to their screens, social medical and video games. They have failed school, and lost jobs. Time spend on screen leads to poor academic performance and may have contributed to the meteoric rise of Attention deficit disorders we are seeing nationwide. Also, people get more sad and anxious when they are indoors under artificial lights. Sunlight causes the production of serotonin which helps in mood regulation. People are more relaxed outdoors in natural settings. No wonder, beaches and mountains still remain the most popular vacation spots. Florescent lights are not continuous lights, but they are vibrating at frequencies. Many people get headaches and migraines working in them.


The harmful effects of junk light are cumulative and does dependent. There is no escape from the blue light as we rely on devices with screens emitting blue light. However, we can take steps to neutralize some of the risks. The best way is to increase your exposure to good light and reduce exposure to bad light.

1. Increase Healthy Light: The healthy light sources are sunlight, natural fire, oil lambs, incandescent lights. It is fairly easy to increase exposure to natural light: Always try to work in a room with a window. If you have a window, open all the curtains. Move your desk close to the window and try to work in natural light. Every 30 minutes to 1 hour, walk outside. If your room has no windows, make it a priority to take scheduled minutes breaks every hour. Go and stand outside and spend some time to get your body adjusted to the sunlight and restore the circadian rhythm. Never look directly at the sun as it will damage the eyes. Whenever possible, work outdoors as long as weather permits. Most people do their exercises indoors, as most gyms are indoors under artificial lights. Exercise is a good time to get healthy light. Choose exercises like walking, jogging, running, cycling, swimming that you can do outdoors. Pick up running, cycling, jogging outdoors.

Natural light through window is good, but not a substitute for direct sun exposure on skin. Most glasses block the ultraviolet rays. UV-B rays are important for the body to make vitamin D. Thus, even if you are by the window all day, there is no substitute for direct sun exposure to the skin. However, limit to no more than 2 hours as excess sun exposure increase risk of skin cancer in people with light skin. Many of us have no control over the busy weekdays. However, when you are off work on weekends, spend more time outdoors. Stockpile on outdoor exposure time when possible to wards of off some of the dangers of blue light exposure during the work week.


2. Reduce Junk Light: The unhealthy light sources are fluorescent light, LED light, and all screen lights from TV, Laptop, and Smart phone. These are all rich in blue lights. They are everywhere. If you work with a screen, add an antiglare protective layer on top of it. Reduce the brightness and contrast of your screen to the lowest setting that you can read comfortably. Adjust the color setting to more towards the red spectrum. Download the software f.lux which allows the computer to go a night mode. I keep the night mode setting for all day. Buy good quality blue light blocking glasses. This will reduce eye strain and protect your eyes. I try to wear the blue light blocking glasses any time I am indoors working with artificial lights like the LED, and Fluorescents looking at a screen. At home, replace all the florescent and LED bulbs with incandescent light. At work, I shut off the room light, and use my own lamb with incandescent light. You can also put a red cover over the light source so that they can block the blue rays.

Artificial light at night is a serious health hazard. The world health organization has classified night light as a carcinogen after studies showed increased risk cancer among night workers. Even a small amount of light at night disrupts the circadian rhythm. For a restful restorative sleep, keep the bedroom completely dark. Shut of all artificial sources of light at night. My bedroom is pitch dark at night with special light blocking curtains. When I am travelling, I unplug all the cords of television, alarm, phone to stop all light sources at night.


A word of caution. The sun rays contain blue light which is maximum during the noon time. Blue light occurring naturally plays a biological role and have some beneficial effects. Short period of blue light exposure has shown to increase energy, focus, mood and alertness. Full spectrum lights rich in blue waves are used in treating the depression associated with the Seasonal affective disorder in winter. However, the beneficial effects of blue light seem to be from short-term exposure. Think of the blue light as a caffeine. A little exposure during the day is OK, and even beneficial. But prolonged exposure will make you more tired, fatigue, and depressed. In summary, humans have evolved to operate in natural sunlight. The artificial light sources specially that from screen, LED, and fluorescents are harmful for our health. During the day, try to work near a window using natural daylight. At night, limit exposure to blue light by using blue light blocking glasses and using incandescent bulbs. Remember, it's not only plants, but humans can also get nourishment from the light. Like junk food, also avoid junk light to improve your health and happiness.