Light Matters: Dr. Achim Leder on How a Chat Sparked the Idea for jetlite


Image: Gabriel Ebensperger

The co-founder and CEO of jetlite, a startup that aims to reduce jet lag with cabin lighting solutions, describes how jet-setting and early tinkerings with electricity landed him where he is today.

To be honest, I am not the type of person who feels bad after a long flight. I might be a little tired, but since I know how to behave before, during and after the flight, I find it fairly easy to deal with jet-lag symptoms.

For long-haul trips, I start adjusting my sleep routine three or four days in advance. For example, in the days before a westbound transatlantic flight that arrives in the United States in the morning, I build up by going to bed an hour later each day and sleeping in for an extra hour. Three days before the flight, I go to bed at midnight instead of 11 p.m. The day before the flight I go to bed at 1 a.m., and then€¯the day of at 2 a.m. By departure time, I’ve adjusted my inner clock by three hours.

I try to travel with pistachios, walnuts and oatmeal. Pistachios support the production of the hormone melatonin, so you can sleep much better after you eat them. Walnuts and oatmeal have the reverse effect and help you wake up much better. I also make sure to exercise and spend some time outside in the sun. Because when it comes to jet lag, I’ve come to realize that, exposing oneself to light is what matters most.

I was at a party where I got to know a professor from the University of Wuppertal, in western Germany near Cologne. I was telling him about how often I flew for work, and he explained to me how light can influence the body’s circadian rhythm. There eventually came a point in the conversation where he said, “I know how light affects the inner clock, and you are a frequent flyer. Is there a chance we can combine both and work together?” I said, “Okay. Let’s bring the sun, in an artificial way, into the aircraft cabin.”

Cold light has a high percentage of blue in it, and it decreases melatonin, helping you wake up.

The decision made me realize that I’d been tinkering with artificial sunlight since I was young. My parents were not always happy about it. They’d follow me around the house, switching off the lights as I’d turn them on. When I was eight years old, I got a model railway and started working with the electricity and adapting the lights. When the train passed certain points on the track, signals would automatically switch on and off. I used a photo sensor to trigger two different scenarios based on day and night. In the day, I used a very clear, cold light, and for night, I used different lamps to create much warmer-toned illuminations.

Despite the electricity bills, my parents let me do what I wanted in my bedroom. But when I suggested adapting lights elsewhere, they drew the line. My modifications looked a little too funny for their liking. My father, who’s an architect, appeased me by letting me pick out and choose proper light fixtures that we could install throughout the home. Everything I chose was based on what I liked – it had nothing to do with research or a scientific background. At that point, it was just an intuitive sense of what I thought was good for us at home.

A few weeks after meeting the professor at the party, we met officially to see how we could put light modulation to the test in airplanes. We decided we needed to run the tests in an aircraft – not only in a laboratory at the university. Luckily, I had worked for Airbus, and my former boss was a member of the airframer’s board of directors. When I called him, he put me in touch with the former director of the German Aerospace Center. They were very interested, but needed a few years before they could run the tests.

Let’s bring the sun, in an artificial way, into the aircraft cabin.

In the end, roused by the enthusiasm from the German Aerospace Center, Airbus provided a wide-body aircraft. Cabin lighting supplier Diehl Aviation came on board, as well as Osram, a German company that provides LED technology for Diehl. So we had a very good consortium – the whole supply chain was involved in the research.

The best light in our life is the sun, but when on board we can improve conditions with LED technology. We modified light according to chronobiological research to simulate different phases. Wake-up scenarios used a colder light, while pre-sleep scenarios used a warmer light. Cold light has a high percentage of blue in it, and it decreases melatonin, helping you wake up.

We decided to run six tests on the ground, because there are too many variables on test flights to be able to compare the results. For each simulation, we measured the melatonin production and heart-rate variability of participants. We also monitored movement, like how often people moved in their seats, walked around, or how frequently they went to the bathroom. After each test, we asked each participant to fill out a questionnaire and rate their sense of well-being, drowsiness and tension. Our results showed that light had a much higher influence on well-being than we expected.

These findings form the basis of the lighting solutions we create at jetlite – and the lighting I use in my own bathroom. I have a switch for the morning and another switch for the evening. When I brush my teeth before bed, I turn on a warm, white light that isn’t too bright so I won’t wake up. The other switch turns on a clear, white light that helps with mornings. I also have a wake-up light in my bedroom that I use during the winter – natural light works better in the summer because no light comes close to the sun.

“Light Matters” was originally published in the 10.2 April/May issue of APEX Experience magazine.