Light is the most essential factor which controls our internal body clock. We need strong regular light signals to have our circadian rhythms on track. Sunrise and sunset used to do the job. However, due to the vicissitudes brought by modern life, these rhythms are disrupted which can lead to health problems, including sleeping disorders. 

Last Friday 22nd September 2017, I attended the seminar, Beat Winter Depression with Dr Norman Rosenthal held in London. I had the opportunity to interview Dr Rosenthal to talk about SAD and light therapy. 

Dr Norman Rosenthal is a South African author, psychiatrist and scientist who in the 1980s first described winter depression or seasonal affective disorder (SAD), and pioneered the use of light therapy for its treatment. 

What led you to investigate seasonal affective disorder?

The way I came to study seasonal affective disorder (SAD) was a combination between my personal story and my scientific journey. I came from South Africa to do my psychiatric residency in New York City, in Columbia. That was 1976. I came from Johannesburg which is much closer to the equator than New York City so the seasons don’t change so much from one to the other and I had not noticed much in the way of my own personal changes with the changing seasons. When I got to New York City, it was during the summer, the days were long.

I had lots of energy and I took on lots of new projects and then after the Daylight Savings Time changed, there was that extra hour of darkness in the afternoon and I really did not know what hit me. With the shorter days I found my own energy levels decreasing and my creativity decreasing.

Frankly, I struggled through the winter and I thought, ‘How could I possibly have taken on all those projects last summer? I must have been crazy!’ But, I struggled through it and then came the spring. Things started to get better and I thought, ‘What was the fuss all about?’ So, that happened for three years: difficulty in the winter; easy-going in the summer and then after that I went to do a research fellowship at the National Institute of Mental Health in Bethesda, Maryland.

The SAD Equinox Seminar took place at an intimate venue overlooking Russell Square in Central London.

What kind of reception did you have when you published your research on SAD? Did you encounter any scepticism?

I encountered a lot of scepticism about the condition and there are still sceptics. I don’t know why they should be. Some people are just die hard sceptics and I have long since decided that I am not going to devote the rest of my professional career trying to convince every sceptic. It’s obvious: there are people who suffer from SAD and the light therapy works for most them and so, that is the situation.

Could you please tell us more about your new book?

The book that has become the New York Times classic landmark book is Winter Blues which is now in its fourth edition. I have updated it with the latest research and it’s a very helpful book that outlines the history of SAD. 

This authoritative book presents a wealth of new information on remedies for seasonal affective disorder (SAD), including recent advances in light therapy, research on the effectiveness of antidepressants, and new recipes to counterbalance unhealthy winter food cravings.

Do you think that SAD affects non-natives more than the indigenous people in colder climates?

It’s a great question and it’s one that has never been satisfactorily answered. Let’s say that a person has this problem in the latent form, and that they are in the tropics and that they moved to the UK and developed winter depression. You never know if they would have it all along if they have been living in the UK all this time.

So you can never know if their tropical background has predisposed them to be less able to tolerate it or it was not revealed because they don’t have the shortage of light in the winter time where they came from. That has never been dissected. But what I can say is that we have no evidence to suggest that where you were born influences the nature of your subsequent symptoms. It’s possible but we just don’t know it at the moment.

Have you done any research to find out if SAD sufferers are more predisposed to mental health disorders?

I would say that SAD sufferers also have anxiety, depression, and premenstrual syndrome. But these are conditions that tend to go together.

Do people from the northern and southern hemispheres get affected by SAD differently?

When it is winter in the northern hemisphere, it is summer in the southern hemisphere, and vice versa.  But despite the difference of when the winter takes places, the symptoms would be the same. But what we need to realise if you look at the globe the land mass is skewed to the north than south. So there would be more people affected by SAD in the north.

How can light boxes help people who are suffering from SAD?

I think they would help them a lot because that is the standard treatment. These products are intended to deliver the right amount of light safely. You can’t just stare at naked light bulbs because that won’t be very good for your eyes.

Bright light therapy is proven to work and offers convenient and natural solutions. These light boxes are designed for use at home, at work or on the go and allow you to fit in your light therapy while you get on with something else.

On the left is Carol Barksfield of The LitePod Company and on the right is Ruth Jackson of Lumie.

The event was a collaborative effort of two leading light box companies in the UK – Lumie and LitePod.

Based just outside Cambridge, Lumie has been researching and designing, and developing light therapy products for over 25 years. Their wealth of technical expertise and consumer feedback goes into creating well-being products that harness the natural benefits of life for a life made bright.

Originally established as Full Spectrum Lighting in the 1980’s to work with the NHS to create medical devices to help sufferers of Seasonal Affective Disorder fight the debilitating symptoms, The Litepod Company now has a varied range of SAD lights designed to give a wide choice of treatments making it much easier for everyone to fit it into their lifestyle and routine.  

Dennis Relojo-Howell is the founder of Psychreg. He writes for the American Psychological Association and has a weekly column for Free Malaysia Today.