Is Light Therapy the Secret to Health?

I don’t know about you, but as I age, I get more anxious. I have ageing parents and growing children. The first have kept me straight to this point in life and the latter need me occasionally to keep them aimed in a useful direction.

As the son of ageing parents, I worry about those diseases that eat away at the humanity of old age, namely Parkinson’s and Alzheimer’s disease. As a father I worry too, though perhaps too much that my children will develop these diseases after a lifetime of increasing risk of depression.

Whilst these diseases have many causes and require a wide range of solutions to their reduction, three papers give me, as a lighting person, hope for the future.

Zang et al in 2023 did a meta-analysis “The effect of light therapy on sleep disorders and psycho-behavioural symptoms in patients with Alzheimer’s disease” which concluded light therapy leads to significant improvement in symptoms of both indicating its potential as a promising treatment option for Alzheimer’s.

Sun et al did a similar meta-analysis of the “Efficacy and Safety of Light Therapy as a Home Treatment for Motor and Non-Motor Symptoms of Parkinson’s Disease” concluding that there is strong evidence that light therapy has significant efficacy on motor and non-motor function in Parkinson’s patients.

The final of the three by Gradisar et al titled “Sleep’s role in the development and resolution of adolescent depression” points to bright light therapy as one possible method of improving sleep and alleviating depression symptoms amongst adolescents.

In summary, light therapy is part of the solution to all. It’s well known that getting older members of our population outside and into the daylight is a problem, especially in the colder months. It’s also well known that with all the fun options to keep children indoors and parental worry about the safety of our children playing outside, a growing proportion of our childhood years are spent inside without daily access to good amounts of daylight. This is evidenced by increasing rates of Vitamin D deficiency (Absoud et al, 2011) and myopia (Guggenheim et al, 2012) in the young.

What’s my recommendation? For the elderly, there may be few options as the ability for individuals to move freely reduces. Whilst 30 minutes of daylight at around lunchtime would be perfect, light therapy of balanced intensity and duration may be the only option. Research suggests 2500 lux for 1-4 hours or more, 2500-10000 lux for 1-2 hours or over 10000 lux for 30-60 minutes. When using artificial light sources, make sure you use one with a full spectrum and preferably with a distribution of that spectrum that’s close to that of daylight. If you are using light therapy glasses then a high illuminance of short wavelength can also work for short periods, though here I have to warn there are risks attached to high-intensity blue light, so do so only under the supervision of an eye specialist. Let me just reinforce that, do NOT buy light therapy glasses off Amazon, go to your doctor! Of course, all artificial light requires energy, also you might struggle to find great light therapy luminaires, so use it only where there is no other choice and consult a specialist for some help.

For the younger generation, the advice is the same, except to say, the young have little trouble getting outdoors and here the blue light risk is significant (Tosini et 2016). So best to kick them outside once a day for a walk or a play in the middle of the day. If you’re worried about the risks, then get a friends group together, or even better, get out with them yourself and let your inner child loose for a while. It will do you good too.

With that, I’m off for a walk with the kids. What are you doing today to prioritise your health?

By maclighter

A Chartered Engineer in Lighting, though trained in mechanical, with 30 years lighting design, technical, manufacture and marketing experience. A trusted mentor, designer, emergency and DIALux trainer, speaker and past president of the Society of Light and Lighting. Get in touch if I can help you out.