The science behind managing your sun exposure – SunSense

The science behind managing your sun exposure

The benefits of sun exposure



Increased mental health

Sunlight triggers the release of serotonin which helps improve our mood, feelings of well-being, and happiness.

Stronger bones

Sun exposure triggers the skin to produce vitamin D, which in turn is an important ingredient for healthy, strong bones.

Cancer prevention

An adequate amount of sunlight have preventive benefits when it comes to certain types of cancer

Healing skin conditions

Sun exposure help treat some skin conditions. Doctors recommend UV exposure to treat e.g. Acne, Psoriasis, Eczema, Jaundice, etc.

The facts of sun overexposure


Develop skin cancer

In the US, 20% (1 out of 5) people are expected to develop skin cancer in their lifetime, and almost 5 million are treated every year.

Caused by UV exposure

90% of all skin cancer cases are caused by UV exposure. Many skin cancers can be avoided by reducing exposure to sunlight.

Cancer cases a form of skin cancer

Globally, 1 in 3 cancer cases are a form of skin cancer, making it one of the most common types in many countries.

About Ultraviolet (UV) rays

Ultraviolet (UV) light is electromagnetic radiation present in sunlight and other sources.

3 different types of UV rays


  • The longest wavelength

  • Reaches deep into the layers of skin causing aging, wrinkling, loose skin and sun spots

  • Sometimes can affect DNA, which increases risk of skin cancer


  • Has largest effect on top layer of skin

  • Causes redness, burning, skin cancer


  • The shortest wavelength

  • Absorbed by the atmospheric ozone and usually do not affect skin



UV Exposure - Benefits and Risks

UV exposure is not that bad. It helps to produce vitamin D that our bodies need and which is important for the immune system. The problem occurs when you you are exposed to too much sun.



  • Production of Vitamin D - Strengthen bones, muscles and the body’s immune system.

  • Mood Improvement - The creation of serotonin is promoted by vitamin D. Serotonin level changes affect mood and behavior.

  • Helps some skin conditions – With moderate phototherapy, successful treatment of eczema, dermatitis, rickets, atopic and localized scleroderma, jaundice, and psoriasis is possible.

  • Skin cancer – Research shows that as many as 90% of skin cancers are due to UV over exposure.

  • Sunburn - The long-term effects of sunburn include premature wrinkling and an increased risk of skin cancer, including melanoma (the most dangerous type of skin cancer.

  • Damaging the immune system – by having a suppressing effect on the immune system

  • Damaging the eyes – e.g. snow blindness (photokeratitis), cataracts and other diseases.

  • Aging the skin – wrinkles, brown "liver" spots, loss of elasticity by destroying collagen and connective tissue beneath the top layer of the skin.

The key to a safer time out in the sun is to avoid sunburn

  • Know strong the UV radiation is at any given moment

  • What that means for your skin type.



Why does it matter and why can't I just use sun screen or the weather forecast?

  1. People have many different skin types and colours giving them very different tolerance to sun exposure. Our skin is almost as individual as our finger prints.

  2. When you use SunSense you will actually get advice on when to use sun screen and which SPF to apply. Or perhaps you think that the sun isn't strong enough today to burn you? You may be in for a painful surprise...

  3. The weather forecast is just that, a forecast. It will tell you the expected UV level for that day, but conditions change and it is the local conditions just where you are, that determine how much UV you are exposed to - in other words: is the sun stronger or weaker that day in your particular location.

Or you might think that controlling your sun exposure is something easy to remember? Well, did you go out in the morning and went back in before lunch? Or did you have to stay outside in the middle of the day when UV is at its most intense? Perhaps you did both.

The point is, your SunSense will automatically and accurately track, accumulate and manage your exposure data so that you don't have to make all those guesses. 

Works for both lighter and darker skin tones

Fair skinned people normally have to worry the most about getting a sunburn which causes increased risk of skin cancer

Dark skinned people often get too little sun exposure to provide enough vitamin D levels. As an example 75-85% of African Americans are considered vitamin D deficient. The problem typically increases with darker skin colour and higher latitude of location.

Overprotection with high SPF sunscreen (that protects much more efficiently against the vitamin D generating UVB rays, than they protect against the "more useless", but still damaging UVA-rays) , generally little outdoor time and poor diet contributes to some 40% of European Americans also being considered vitamin D deficient.

If your intention is to get a tan, then very often the limit where sunburn starts to occur comes much closer. Using a sensor that tracks your UV-exposure real time and tells you when it's time to go into the shadow or put on some clothes, is a new and effective way to stay in control and avoid the immediate pains and excessive risks of long-term effects associated with sunburns.

Living with your skin disease

A number of skin conditions are affected by sunlight in different ways. Some of these groups can have great benefits of being able to measure and control the actual exposure to take the guesswork and anxiety away from their outdoor lives:

Polymorphous Light Eruption (PLE) sometimes known as "sun eczema" is an itching rash that is triggered by sun exposure at very different individual levels. It affects as much as 10-20% of the population in typical temperate climates. Gradual increase in sun exposure can have a desensitizing effect on many with this condition. Being able to find your personal sun exposure or UV-dose limit and controlling this regardless of sun conditions that vary greatly from day to day and hour to hour is key.

Lupus is an autoimmune disease that can affect many different body systems. Some 40-70% of people with lupus find that the disease is made worse by sunlight, some even by the small amounts of UV sometimes present in indoor lighting. It can result in flares triggering a range of serious symptoms. Many people with this condition are used to protecting themselves extremely well against sun exposures when going outside for even very short periods. Because what is considered "outside daylight" can vary in intensity by a factor of more than 50 without the naked eye being able to distinguish it properly. The same short walk outside could be triggering a flare one day, and be completely safe another day at another time.

Psoriasis is an autoimmune disease affecting a large number of people causing red, scaly and itching patches. Artificial UV--radiation or natural sun exposure is commonly used to relieve the symptoms of this condition. Managing the total daily dose of UV-exposure when using the outside sun as a treatment, either with or without sunscreen is of vital importance.

Vitiligo is another autoimmune condition in which areas of the skin lose pigment causing them to appear white. It frequently affects the face and back of hands and occurs in all skin types, but are more visible in the darker ones. No drugs can stop the process of vitiligo, but some drugs alone or together with UVB light therapy can help restore some of the skin tone. Because the affected patches of skin actually lack the natural UV-light protection (pigment) these areas are much more prone to become sunburnt.

Did you know?

People that receive moderate to high doses of sun exposure throughout the year without burning actually show a 40% reduction in melanoma (mole) cancer incidence. And those that do so, see a higher survival rate.

Non-melanoma skin cancers are rarely deadly, but often affects the face and head and can require extensive surgery. The incidence of these increases with long term sun exposure and are most frequent with elderly people.

A large number of scientific studies have shown that vitamin D and UV-exposure reduces both incidence and mortality of a multitude of diseases. For several of these the mechanisms are other than the sun induced generation of vitamin D, and supplements can not give the full benefits as achieved by exposing the body to UV.

A 20-year long Swedish study of sun exposure as a risk factor for major causes of death on 29.518 women showed significant correlation with Cardiovascular Diseases (CVD), Cancer and Other causes of death. The study indicated that "avoidance of sun exposure is a risk factor of death of a similar magnitude as smoking "

Light skin developed as a response to much lower sun intensities when our ancestors emigrated out of Africa as it can much more effectively utilize the sunlight. Skin cancer has presumably not been an evolutionary factor as this most often occurs after carrying on the family and genes.

Everyone agrees that sunburn damages the skin and increases the risk of skin cancer dramatically. The effect is biggest for sun burns in early years.



Healthline - The Benefits of Vitamin D

Vitamin D Deficiency. N Engl J Med 2001: 357: 266-281

Skin Cancer Foundation

US Surgeon General

World Health Organization